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Food science technology, Sciences technologies alimentaires, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Toxicologie, Toxicology, Toxicologie des pesticides, engrais et autres produits chimiques à usage agricole, Pesticides, fertilizers and other agrochemicals toxicology, Toxicologie alimentaire, Food toxicology, Céréale, Cereal, Dérivé d'azole, Azole derivatives, Azol derivado, Dérivé du triazole, Triazole derivatives, Triazol derivado, Pesticide, Pesticides, Plaguicida, Blé, Wheat, Trigo, Chinois, Chinese, Chino, Cinétique, Kinetics, Cinética, Fongicide, Fungicide, Fungicida, Propiconazole, Résidu, Residue, Resíduo, Sol, Soils, Suelo, Difenoconazole, Dissipation kinetics, Residues, and Soil

An analytical method for simultaneously determining the residues of difenoconazole and propiconazole in wheat straw, wheat grain and soil was developed. Mean recoveries and relative standard deviations in all samples ranged 86.2―101.3% and 3.1―12.1% for propiconazole and difenoconazole. The half-lives of difenoconazole and propiconazole were 3.6―5.5 days and 5.1―6.9 days in wheat straws, and 4.9―5.8 days and 6.1―8.4 days in soil, respectively. The residues in wheat grain were found to be <0.01 mg/kg, based on the application rate (135 g a.i./ha) and the pre-harvest interval (PHI = 28 days) recommended by the manufacturer. The results suggest that the use of difenoconazole and propiconazole on wheat is considered to be safe under the Good Agricultural Practices (GAP) in the Chinese fields, and the main factors for pesticide residue in crops are application times, rates and pre-harvest intervals.

Food science technology, Sciences technologies alimentaires, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Toxicologie, Toxicology, Toxicologie alimentaire, Food toxicology, Fruit, Fruto, Origine végétale, Plant origin, Origen vegetal, Polyoside, Polysaccharide, Poliósido, Cinétique, Kinetics, Cinética, Pectine, Pectin, Pectina, Purification, Purificación, Pêche (fruit), Peach, Durazno, EC 1.10.3.1, and Polyphenol oxidase

Polyphenol oxidase (PPO) was purified from peach pulp by a three-step column chromatographic procedure. The kinetics properties of the PPO fractions obtained from different purification steps were compared. All the fractions showed high affinities for (+)-catechin and (-)-epicatechin. The optimum pHs and optimum temperatures for all the fractions were the same. However, the fraction that contained pectin was more sensitive to the change of pH, and it had a lower affinity for the substrates and a higher thermostability than the fractions without pectin. In addition, the protein impurities in PPO fractions might have no effect on the properties of PPO. L-Cysteine and glutathione were effective for the inhibition of all the PPO fractions, while NaF inhibited moderately. However, the pectin could reduce the inhibition effects of those inhibitors.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Amine polymère, Amine polymer, Amina polímero, Amine tertiaire, Tertiary amine, Amina terciaria, Cinétique, Kinetics, Cinética, Colorant organique, Organic dye, Colorante orgánico, Effet structure, Structure effect, Efecto estructura, Effet température, Temperature effect, Efecto temperatura, Etude expérimentale, Experimental study, Estudio experimental, Gel colloïdal, Colloidal gel, Gel coloidal, Gonflement, Swelling, Inflamiento, Libération, Release, Liberación, Méthacrylate polymère, Methacrylate polymer, Metacrilato polímero, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation radicalaire, Free radical polymerization, Polimerización radicalar, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Préparation, Preparation, Preparación, Rhodamine, Rodamina, Triazole dérivé polymère, Triazole derivative polymer, Triazol derivado polímero, Vecteur médicament, Drug carrier, Vector medicamento, pH, Effet densité réticulation, Interaction pi pi, Polymère sensible stimuli, DMAEMA, anticancer, hydrogels, sustained release, and triazole

The purpose of this study is to develop novel triazole-containing hydrogels (TGs) as drug carrier and to investigate the sustained drug release accomplished by their time-dependent swelling behavior. The synthetic pathway of TGs includes: (1) DCC-coupling on hydroxyethyl methacrylate (HEMA) to prepare HEMA-alkyne (HA), (2) click-coupling to prepare a triazole-ring-containing monomer (TM), and (3) the synthesis of a series of TGs. The aggregation between triazole rings is found to be responsible for drug release controllability. Rhodamine 6G is studied as a model anticancer drug for release experiments. The effects of pH and temperature on the properties of sustained drug release are also studied.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés spéciales (catalyseur, réactif ou support), Special properties (catalyst, reagent or carrier), Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Adhérence, Adhesion, Adherencia, Article synthèse, Review, Artículo síntesis, Cinétique, Kinetics, Cinética, Libération, Release, Liberación, Muqueuse, Mucosa, Mécanisme, Mechanism, Mecanismo, Polymère vecteur, Control release polymer, Polímero vector, Vecteur médicament, Drug carrier, Vector medicamento, Mucoadhérence, Mucoadhésif, Mucoadhesive drug delivery systems, Mucoadhesive natural, synthetic and semi-synthetic polymers, and Pharmaceutical materials science pharmaceutical research and development

The presence of a mucus layer that covers the surface of a variety of organs has been capitalized to develop mucoadhesive dosage forms that remain in the administration site for prolonged times, increasing the local and/or systemic bioavailability of the administered drug. The emergence of micro and nanotechnologies together with the implementation of non-invasive and painless administration routes has revolutionized the pharmaceutical market and the treatment of disease. Aiming to overcome the main drawbacks of the oral route and to maintain patient compliance high, the engineering of innovative drug delivery systems administrable by mucosal routes has come to light and gained the interest of the scientific community due to the possibility to dramatically change pharmacokinetics. In addition, to achieve the goal of mucosal drug administration, the development of biomaterials has been refined to fit specific applications. The present review initially describes the potential of nano-drug delivery systems conceived for mucosal administration by diverse non-parenteral routes (e.g., oral, inhalatory, etc.). Then, the benefit of the incorporation of mucoadhesive polymers into the structure of these innovative pharmaceutical products to prolong their residence time in the administration site and the release of the drug cargo will be discussed with focus in the developments of the last decade. In addition, the regulatory status of the most extensively used mucoadhesive polymers will be emphasized. Finally, a thorough overview of the different pharmaceutical applications of mucoadhesive polymers will be addressed.

Urology, nephrology, Urologie, néphrologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Nephrologie. Maladies des voies urinaires, Nephrology. Urinary tract diseases, Tumeurs de l'appareil urinaire, Tumors of the urinary system, Voies urinaires. Prostate, Urinary tract. Prostate gland, Gynecologie. Andrologie. Obstetrique, Gynecology. Andrology. Obstetrics, Pathologie de l'appareil génital mâle, Male genital diseases, Tumeurs, Tumors, Cancer, Cáncer, Pathologie de l'appareil génital mâle, Male genital diseases, Aparato genital macho patología, Pathologie de l'appareil urinaire, Urinary system disease, Aparato urinario patología, Pathologie de la prostate, Prostate disease, Prostata patología, Tumeur maligne, Malignant tumor, Tumor maligno, Antigène spécifique prostate, Prostate specific antigen, Antigeno específico prostata, Cancer de la prostate, Prostate cancer, Cáncer de la próstata, Cinétique, Kinetics, Cinética, Décision, Decision, Decisión, Marqueur tumoral, Tumoral marker, Marcador tumoral, Néphrologie, Nephrology, Nefrología, Prise de décision, Decision making, Toma decision, Temps doublement, Doubling time, Tiempo duplicación, Urologie, Urology, Urología, Vitesse, Velocity, and Velocidad

Although the value of prostate-specific antigen (PSA) velocity or doubling time has never been seriously questioned for aiding the clinical management of recurrent or advanced cancer, there has historically been considerable uncertainty about PSA kinetics for decisions about biopsy and initial treatment. Recent studies, including analyses of cohorts from all the major randomized trials of localized prostate cancer, have failed to find any evidence that PSA velocity and application of PSA cutpoints are of benefit in this setting. Given current data on PSA velocity and doubling time, we propose the following take home messages for the practicing urologist: (1) High PSA velocity is not an indication for biopsy; (2) for men with a low total PSA but a high PSA velocity, consideration should be given to having PSA taken at a shorter interval; (3) men with an indication for biopsy should be biopsied irrespective of PSA velocity; (4) changes in PSA after negative biopsy findings do not determine the need for repeat biopsy; (5) monitoring PSA over time can aid judgment in decisions about biopsy, as informed by the clinical context; (6) PSA velocity is uninformative of risk at diagnosis; (7) high PSA velocity is not an indication for treatment in men on active surveillance; (8) PSA velocity at the time of recurrence should be entered into prediction models (or nomograms) to aid patient counseling; (9) PSA changes after treatment for advanced disease can help indicate therapeutic response.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Oside polymère, Oside polymer, Osido polímero, Propriété biologique, Biological properties, Propiedad biológica, Alginate, Alginates, Alginato, Autoassemblage, Self assembly, Autoensamble, Biocompatibilité, Biocompatibility, Biocompatibilidad, Cinétique, Kinetics, Cinética, Couche autoassemblée, Self-assembled layer, Capa autoensamblada, DNA, Ethylèneimine polymère, Polyethylene imine, Etilenoimina polímero, Etude expérimentale, Experimental study, Estudio experimental, Fibroblaste, Fibroblast, Fibroblasto, In vitro, Libération, Release, Liberación, Multicouche, Multiple layer, Capa múltiple, Polymère vecteur, Control release polymer, Polímero vector, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Transfection, Transfección, Vecteur médicament, Drug carrier, Vector medicamento, Gene delivery, In situ transfection, Layer-by-layer assembly, and Polyelectrolyte multilayer

Alginate has been previously utilized as an adjuvant in nanoparticle-mediated gene delivery. In this study, we investigated the extent to which alginate promotes in situ transfection from polyelectrolyte multilayers (PEMs). After spiking free alginate molecules, DNA release from PEMs was increased and transgene expression was enhanced, suggesting that alginate may compete with DNA to weaken electrostatic interaction within PEMs. Consequently, alginate was applied to compose multilayers with DNA and polyethyleneimine (PEI). Interestingly, the incorporated alginate increased not only deposition but also delivery of DNA from PEMs. Quartz crystal microbalance (QCM) analysis suggested that the deposited alginate enhanced PEI adsorption which in turn augmented subsequent DNA deposition. In situ transfection experiments revealed that alginate within PEMs improved not only the level but also the duration of transgene expression. This system should be a potential strategy to regulate gene delivery from scaffolds for tissue engineering application.

Mechanical engineering, Génie mécanique, Materials, Matériaux, Metrology and instrumentation, Métrologie et instrumentation, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Radiotherapie. Traitement instrumental. Physiotherapie. Reeducation. Readaptation, orthophonie, crenotherapie. Traitement dietetique et traitements divers (generalites), Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects), Technologie. Biomatériaux. Equipements. Matériel. Appareillage, Technology. Biomaterials. Equipments. Material. Instrumentation, Articulation tibiotarsienne, Ankle joint, Articulación tibiotarsal, Cinématique, Kinematics, Cinemática, Cinétique, Kinetics, Cinética, Genou, Knee, Rodilla, Sport, Deporte, Vitesse angulaire, Angular velocity, ACL injury, Ankle, and Single-leg landing

Anterior cruciate ligament (ACL) injury often occurs among athletes during single-leg landing. Wearing shoes could alter lower extremity kinematics and kinetics and affect the risk of ACL injury. This study aimed to investigate knee and ankle kinematics and kinetics during single-leg landing in shod and barefoot conditions. Nineteen males performed single-leg landings by stepping off a 0.3-meter platform in shod and barefoot conditions. Three-dimensional lower limb kinetics and kinematics were calculated using a force plate and motion analysis system. The present study found that the peak knee valgus moment (p=0.024), peak anterior tibial translation (ATT) (p=0.022), and peak knee flexion angle (p<0.01) are greater during shod landing. In addition, the peak ankle inversion (p<0.01), peak eversion moment (p=0.032), and peak eversion angular velocity (p<0.01) were higher during shod landing. In conclusion, the increased knee valgus moment and ankle eversion moment suggest that shod conditions increase the risk of ACL injury; however, higher ATT and knee flexion angle during shod landing were not associated with increased risk of ACL injury. Further, the higher ankle movement in the coronal plane during shod conditions appears to increase the risk of ankle injury.

Orthopedics traumatology, Orthopédie, traumatologie, Applied physiology, ergonomics sports medicine, Physiologie appliquée, ergonomie, sport, Rheumatology, Rhumatologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Vertebres: mouvements corporels. Posture. Locomotion. Vol. Nage. Exercice physique. Repos. Sports, Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports, Sciences medicales, Medical sciences, Traumatismes. Maladies dues aux agents physiques, Traumas. Diseases due to physical agents, Traumatismes des membres. Traumatismes du rachis, Injuries of the limb. Injuries of the spine, Physiologie humaine appliquee a l'etude des populations et des conditions de vie. Ecophysiologie humaine, Human physiology applied to population studies and life conditions. Human ecophysiology, Biomécanique, Biomechanics, Biomecánica, Cinétique, Kinetics, Cinética, Exercice physique, Physical exercise, Ejercicio físico, Fonctionnement, Running, Funcionamiento, Lésion, Lesion, Lesión, Manipulation, Manipulación, Plantaire, Plantar, Plante pied, Foot sole, Planta pie, Pression, Pressure, Presión, Sportif, Athlete, Deportista, Traumatisme, Trauma, Traumatismo, Course à pied, biomechanics, cadence, kinetics, overuse injury, pressure, and running

Our purpose was to evaluate effects of cadence manipulation on plantar loading during running. Participants (n=38) ran on a treadmill at their preferred speed in 3 conditions: preferred, 5% increased, and 5% decreased while measured using in-shoe sensors. Data (contact time [CT], peak force [PF], force time integral [FTII, pressure time integral [PTI] and peak pressure [PP]) were recorded for 30 right footfalls. Multivariate analysis was performed to detect differences in loading between cadences in the total foot and 4 plantar regions. Differences in plantar loading occurred between cadence conditions. Total foot CT and PF were lower with a faster cadence, but no total foot PP differences were observed. Faster cadence reduced CT, pressure and force variables in both the heel and metatarsal regions. Increasing cadence did not elevate metatarsal loads; rather, total foot and all regions were reduced when healthy runners increased their cadence. If a 5 % increase in cadence from preferred were maintained over each mile run the impulse at the heel would be reduced by an estimated 565 body weights*s (BW*s) and the metatarsals 140-170 BW*s per mile run despite the increased steps taken. Increasing cadence may benefit overuse injuries associated with elevated plantar loading.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Oside polymère, Oside polymer, Osido polímero, Activité biologique, Biological activity, Actividad biológica, Anticancéreux, Antineoplastic agent, Anticanceroso, Cancer de la prostate, Prostate cancer, Cáncer de la próstata, Cellule tumorale, Tumor cell, Célula tumoral, Cinétique, Kinetics, Cinética, Constante stabilité, Stability constant, Constante estabilidad, Cyclodextrine, Cyclodextrin, Ciclodextrina, Dissolution, Disolución, Etude expérimentale, Experimental study, Estudio experimental, Hydrosolubilité, Water solubility, Hidrosolubilidad, In vitro, Libération, Release, Liberación, Morphologie, Morphology, Morfología, Polymère vecteur, Control release polymer, Polímero vector, Stoechiométrie, Stoichiometry, Estequiométría, Telmisartan, Telmisartán, Vecteur médicament, Drug carrier, Vector medicamento, Cyclodextrine(hydroxypropyl), 2-HP-β-CD, Complex, Cytotoxicity, In silico docking, and Solubility

Telmisartan (TEL) requires superior bioavailability in cancer cell compartments. To meet these challenges, we have synthesized a 2-HP-β-CD-TEL complex with stability constant (Kc) of 2.39 × 10―3 mM. The absence in the FTIR spectrum of 2-HP-β-CD-TEL complex of the characteristic peaks of TEL at 1699 cm―1 (carboxylic acid) and 741 and 756 cm―1 (1,2-disubstituted benzene ring vibrations), is indicative of the encapsulation of TEL in the 2-HP-β-CD cavity. DSC and PXRD also confirmed the synthesis and amorphous structure of complex. The interaction of TEL with 2-HP-β-CD was examined by NMR and 2D-ROESY which affirms the encapsulation of TEL in the 2-HP-β-CD cavity in at least two orientations with equal binding energies. The complex also exhibited its superiority in both in vitro release and cytotoxicity experiments on prostate cancer, PC-3 cells as compared to free drug. These data warrant an in depth in vivo to scale-up the technology for the management of prostate cancer.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Angiospermae, Dicotyledones, Leguminosae, Oside polymère, Oside polymer, Osido polímero, Propriété surface, Surface properties, Propiedad superficie, Spermatophyta, Adhésivité, Adhesivity, Adhesividad, Analyse texture, Texture analysis, Análisis textura, Chitosane, Chitosan, Quitosano, Cinétique, Kinetics, Cinética, Comprimé enrobé, Coated tablet, Tableta cubierta, Dépôt projection, Spray coating, Depósito proyección, Etude expérimentale, Experimental study, Estudio experimental, In vitro, Interaction intermoléculaire, Intermolecular interaction, Interacción intermolecular, Libération, Release, Liberación, Matériau revêtement, Coating material, Material revestimiento, Morphologie, Morphology, Morfología, Mouillabilité, Wettability, Remojabilidad, Mélange polymère, Polymer blends, Mésalazine, Mesalazine, Mesalazina, Pectine, Pectin, Pectina, Potentiel électrocinétique, Electrokinetic potential, Potencial electrocinético, Propriété mécanique, Mechanical properties, Propiedad mecánica, Tamarindus indica, Transition thermique, Thermal transition, Transición térmica, Adhesive force strength, CH-TP films, Film rolling effect, Tablet coating material, and Tamarind pectin

Tablet coating is the most useful method to improve tablet texture, odour and mask taste. Thus, the present investigation was aimed at developing an industrially acceptable aqueous tablet coating material. The physico-chemical, electrical and SEM investigations ensures that blending of Tamarindus indica (Linn.) pectin (TP) with chitosan gives water resistant film texture. Therefore, CH-TP (60:40) spray coated tablets were prepared. The evaluation of CH-TP coated tablets showed enhanced adhesive force strength (between tablet surface to coat) and negligible cohesive force strength (between two tablets) both evaluated using texture analyzer. The comparison of CH-TP coated tablets with Eudragit coated tablets further supported superiority of the former material. Thus, the findings pointed towards the potential of CH-TP for use as a tablet coating material in food as well as pharmaceutical industry.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Hormones. Glandes endocrines, Hormones. Endocrine system, Animal, Mammalia, Oside polymère, Oside polymer, Osido polímero, Propriété surface, Surface properties, Propiedad superficie, Rodentia, Vertebrata, Activité biologique, Biological activity, Actividad biológica, Adhésivité, Adhesivity, Adhesividad, Cinétique, Kinetics, Cinética, Condition opératoire, Operating conditions, Condición operatoria, Encapsulation, Encapsulación, Etude expérimentale, Experimental study, Estudio experimental, Fabrication, Manufacturing, Fabricación, Glycémie, Glycemia, Glucemia, Gomme gellane, Gellan gum, Goma gellan, Gomme tamarin, Tamarind gum, Goma tamarín, Gonflement, Swelling, Inflamiento, Gélification, Gelation, Gelificación, Hydrogel, Hidrogel, Hypoglycémiant, Hypoglycemic agent, Hipoglicemiante, In vitro, In vivo, Ion calcium, Calcium ion, Calcio ión, Libération, Release, Liberación, Muqueuse, Mucosa, Méthodologie surface réponse, Response surface methodology, Optimisation, Optimization, Optimización, Particule sphérique, Spherical particle, Partícula esférica, Polymère vecteur, Control release polymer, Polímero vector, Rat, Rata, Vecteur médicament, Drug carrier, Vector medicamento, Gel ionotrope, Gel mixte, Mucoadhésif, Controlled drug release, Metformin HCl, Mucoadhesion, Polymer-blend, and Tamarind seed polysaccharide

The paper describes the development, optimization and evaluation of tamarind seed polysaccharide (TSP)-blended gellan gum (GG) mucoadhesive beads containing metformin HCl through Ca2+-ion crosslinked ionic gelation for oral drug delivery. Effects of GG to TSP ratio and cross-linker (CaCl2) concentration on the drug encapsulation efficiency (DEE, %), and cumulative drug release after 10 h (R10h, %) of TSP―GG mucoadhesive beads containing metformin HCl were optimized by 32 factorial design. The optimized mucoadhesive beads (F-O) showed DEE of 95.73 ± 4.02%, R10h of 61.22 ± 3.44% and mean diameter of 1.70 ± 0.24mm. These beads were characterized by SEM and FTIR analyses. The in vitro drug release from these beads showed controlled-release (zero-order) pattern over a period of 10h. The optimized TSP―GG mucoadhesive beads also exhibited pH-dependent swelling, good mucoadhesivity with biological mucosal membrane and significant hypoglycemic effect in alloxan-induced diabetic rats over prolonged period after oral administration.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Oside polymère, Oside polymer, Osido polímero, Structure moléculaire, Molecular structure, Estructura molecular, Acrylamide polymère, Acrylamide polymer, Acrilamida polímero, Alginate, Alginates, Alginato, Analgésique, Analgesic, Analgésico, Cinétique, Kinetics, Cinética, Densité réticulation, Crosslink density, Densidad reticulado, Etude expérimentale, Experimental study, Estudio experimental, Gel colloïdal, Colloidal gel, Gel coloidal, Gonflement, Swelling, Inflamiento, In situ, In vitro, Libération, Release, Liberación, Morphologie, Morphology, Morfología, Paracétamol, Paracetamol, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation radicalaire, Free radical polymerization, Polimerización radicalar, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Préparation, Preparation, Preparación, Réseau polymère semiinterpénétré, Semiinterpenetrating polymer network, Red polímero semiinterpenetrado, Vecteur médicament, Drug carrier, Vector medicamento, pH, Acrylamide, Characterization, Drug release, Semi-IPN hydrgels, and Sodium alginate

Several semi interpenetrating network (SIPN) type hydrogels were synthesized by in-situ free radical crosslink copolymerization of acrylamide and crosslinker N,N'-methylene bisacrylamide (MBA) in aqueous solution of sodium alginate (SA).These SIPN hydrogels were characterized by FTIR, NMR SEM, DTA―TGA, XRD, PZC and also by swelling characteristics and network parameters. Adsorption (loading) and release of acetaminophen drug were studied with these hydrogels. Solution pH, crosslinker concentration and monomer to SA weight ratio of the hydrogels were found to have a strong effect on adsorption and in vitro release profile of the drug from the gel matrix.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Lactone copolymère, Lactone copolymer, Lactona copolímero, Propriété biologique, Biological properties, Propiedad biológica, Propriété optique, Optical properties, Propiedad óptica, Propriété électrique, Electrical properties, Propiedad eléctrica, Acide copolymère, Acid copolymer, Acido copolímero, Caprolactone copolymère, Caprolactone copolymer, Caprolactona copolímero, Cinétique, Kinetics, Cinética, Colorant organique, Organic dye, Colorante orgánico, Conductivité électrique, Electrical conductivity, Conductividad eléctrica, Copolymère greffé, Graft copolymer, Copolímero injertado, Copolymère triséquencé, Triblock copolymer, Copolímero trisecuencia, Cytotoxicité, Cytotoxicity, Citotoxicidad, Etude expérimentale, Experimental study, Estudio experimental, Fluorescence, Fluorescencia, Greffage, Grafting, Injerto, In vitro, Libération, Release, Liberación, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Polymère conducteur, Conducting polymers, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation ouverture cycle, Ring opening polymerization, Polimerización abertura ciclo, Polymérisation oxydante, Oxidative polymerization, Polimerizacion oxidante, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Préparation, Preparation, Preparación, Réaction successive, Successive reaction, Reacción consecutiva, Stabilité thermique, Thermal stability, Estabilidad térmica, THF, Tetrahydrofurane, Furano(tetrahidro), Terpolymère, Terpolymer, Terpolímero, Tétrahydrofurane copolymère, Tetrahydrofuran copolymer, Tetrahidrofurano copolímero, Vecteur médicament, Drug carrier, Vector medicamento, pH, Aniline dérivé copolymère, Aniline derivative copolymer, Aniline(3-carboxy) copolymère, Characterization, Conductivity, Cyclic voltammetry, and Drug release system

The poly(tetrahydrofuran) (PTHF) grafted poly(caprolactone)-poly(anthranilicacid)-poly(caprolactone) (PCL-PAA-PCL) co-polymer system was synthesized by using a prepolymer under nitrogen atmosphere in the presence of a stannous octoate catalyst. The [M0/l0] was maintained at 100. The polymers at each stage was characterized by various analytical techniques like FTIR spectroscopy, NMR spectroscopy, UV-visible spectroscopy, fluorescence spectroscopy, cyclic voltammetry, DSC, TGA, conductivity, FESEM, solubility test, cytotoxicity and drug release study. The results obtained here in the present investigation are critically compared with the literature values.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Propriété biologique, Biological properties, Propiedad biológica, Propriété mécanique, Mechanical properties, Propiedad mecánica, Acrylamide dérivé copolymère, Acrylamide derivative copolymer, Acrilamida derivado copolímero, Acrylate copolymère, Acrylate copolymer, Acrilato copolímero, Acrylique acide copolymère, Acrylic acid copolymer, Acrílico ácido copolímero, Amidoamine copolymère, Amidoamine copolymer, Amidoamina copolímero, Amidoamine polymère, Amidoamine polymer, Amidoamina polímero, Biocompatibilité, Biocompatibility, Biocompatibilidad, Biodégradabilité, Biodegradability, Biodegradabilidad, Biomatériau, Biomaterial, Cellule mésenchymateuse, Mesenchymal cell, Célula mesenquimatosa, Cellule souche, Stem cell, Célula primitiva, Charpente, Framework, Armadura, Cinétique, Kinetics, Cinética, Copolymérisation radicalaire, Radical copolymerization, Copolimerización radical, Encapsulation, Encapsulación, Etude expérimentale, Experimental study, Estudio experimental, Forme injectable, Injectable form, Forma inyectable, Gonflement, Swelling, Inflamiento, Gélification, Gelation, Gelificación, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Hydrogel, Hidrogel, Hydrolyse, Hydrolysis, Hidrólisis, In vitro, Module compression, Bulk modulus, Módulo volumétrico, Méthacrylate de glycidyle copolymère, Glycidyl methacrylate copolymer, Metacrilato de glicidilo copolímero, Préparation, Preparation, Preparación, Réticulation, Crosslinking, Reticulación, Solution aqueuse, Aqueous solution, Solución acuosa, Tissu osseux, Osseous tissue, Tejido óseo, Acrylamide(N-isopropyl) copolymère, Copolymère sensible stimuli, Gel hybride, and Quaterpolymère

Injectable, dual-gelling hydrogels were successfully developed through the combination of physical thermogellation at 37 °C and favorable amine:epoxy chemical cross-linking. Poly(N-isopropylacrylamide)-based thermogelling macromers with a hydrolyzable lactone ring and epoxy pendant groups and a biodegradable diamine-functionalized polyamidoamine cross-linker were synthesized, characterized, and combined to produce nonsyneresing and bioresorbable hydrogels. Differential scanning calorimetry and oscillatory rheometry demonstrated the rapid and dual-gelling nature of the hydrogel formation. The postgelation dimensional stability, swelling, and mechanical behavior of the hydrogel system were shown to be easily tuned in the synthesis and formulation stages. The leachable products were found to be cytocompatible under all conditions, while the degradation products demonstrated a dose- and time-dependent response due to solution osmolality. Preliminary encapsulation studies showed mesenchymal stem cell viability could be maintained for 7 days. The results suggest that injectable and thermally and chemically cross-linkable hydrogels are promising alternatives to prefabricated biomaterials for tissue engineering applications, particularly for cell delivery.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Préparation, cinétique, thermodynamique, mécanisme et catalyseurs, Preparation, kinetics, thermodynamics, mechanism and catalysts, Polymères à propriétés spéciales, Polymers with particular properties, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Lactone copolymère, Lactone copolymer, Lactona copolímero, Acidolyse, Acidolysis, Acidolisis, Acrylique acide copolymère, Acrylic acid copolymer, Acrílico ácido copolímero, Antiinflammatoire non stéroïde, Non steroidal antiinflammatory agent, Antiinflamatorio no esteroide, Caprolactone copolymère, Caprolactone copolymer, Caprolactona copolímero, Cinétique, Kinetics, Cinética, Concentration critique micellaire, Micellar critical concentration, Concentración crítica micelar, Ethylène oxyde copolymère, Ethylene oxide copolymer, Etileno óxido copolímero, Etude expérimentale, Experimental study, Estudio experimental, In vitro, Libération, Release, Liberación, Modification chimique, Chemical modification, Modificación química, Nanoencapsulation, Nanoencapsulación, Naproxène, Naproxen, Naproxeno, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Polymère monodispersé, Monodispersed polymer, Polímero monodispersado, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation ouverture cycle, Ring opening polymerization, Polimerización abertura ciclo, Polymérisation transfert atome, Atom transfer polymerization, Polimerización transferencia atomo, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Préparation, Preparation, Preparación, Solution aqueuse, Aqueous solution, Solución acuosa, Solution micellaire, Micellar solution, Solución micelar, Spectre dimension, Dimension spectrum, Espectro dimensión, Terpolymère, Terpolymer, Terpolímero, Vecteur médicament, Drug carrier, Vector medicamento, pH, Acrylate de tert-butyle copolymère, Copolymère pentaséquencé, Atom transfer radical polymerization, Nanomicelles, Ring-opening polymerization, and pH-sensitive block copolymer

A series of poly(acrylic acid)-poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone)-poly(acrylic acid) pH-sensitive PEG-[b-PCL-b-PAA]2 pentablock copolymers were synthesized via a combination of ring-opening polymerization (ROP), atom transfer radical polymerization (ATRP) and acidolysis. First, hydroxyl-terminated PEG (Mn = 4000 g mol-1) was used as starting material and stannous octanoate (Sn(Oct)2) as a catalyst for ROP of ε-caprolactone (CL). Then, the macroinitiator transformed from PEG-[b-PCL]2 (Mn = 13,700 and 21,800 g mol-1, by GPC) in high conversion initiated ATRPs of tert-butyl-acrylate (tBA) to construct PEG-[b-PCL-b-PtBA]2 (Mn = 17,000-26.000 g mol-1; Mw/ Mn = 1.13-1.25). Finally, the PEG-[b-PCL-b-PAA]2 was obtained via the acidolysis of the PtBA segment in PEG-[b-PCL-b-PtBA]2. The composition of triblock and pentablock copolymers was controlled by changing the feed ratios of CL/PEG in ROP and time in ATRP. The chain structures of copolymers were characterized by FT-IR, 1H NMR, and gel permeation chromatography (GPC). These copolymers are self-assembled into spherical nano size micelles in aqueous solution at pH < 4.5. The formation, size and morphology of nanomicelles were studied by scanning electron microscopy (SEM), dynamic light scattering (DLS) and by measuring the critical micelle concentration (CMC) using fluorescence spectroscopy. The loading and controlled release of naproxen as a model drug was investigated, and it was found that the total release in the buffer solution at pH 7.4 is higher than that at pH 4.2.

Biomedical engineering, Génie biomédical, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Biocompatibilité, Biocompatibility, Biocompatibilidad, Biomatériau, Biomaterial, Cinétique, Kinetics, Cinética, Fibroblaste, Fibroblast, Fibroblasto, Gel colloïdal, Colloidal gel, Gel coloidal, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Libération, Release, Liberación, Polymère vecteur, Control release polymer, Polímero vector, Procédé sol gel, Sol gel process, Procedimiento sol gel, Propriété biologique, Biological properties, Propiedad biológica, Préparation, Preparation, Preparación, Silice, Silica, Sílice, Silicium Oxyde, Silicon Oxides, Silicio Óxido, Synthèse, Synthesis, Síntesis, Vecteur médicament, Drug carrier, Vector medicamento, Verre, Glass, Vidrio, Bioverre, biocompatibility, bioglasses, drug release, and sol―gel

SiO2 glass has been synthesized via sol―gel process and enriched with 5 wt % sodium ampicillin. To verify the biocompatibility of the obtained biomaterial, fibroblasts have been grown on a glass surface and were tested for viability after 24 h. The results of the Water-Soluble Tetrazolium (WST)-8 analysis suggest that SiO2 glass has an adequate biocompatibility. The amorphous nature of the gels has been ascertained by X-ray diffraction analysis. Release kinetics have been subsequently investigated in a simulated body fluid. The amount of sodium ampicillin released has been detected by ultraviolet-visible spectroscopy. The release kinetics seems to occur in more than one stage. High-performance liquid chromatography analysis has also been carried out to ensure the integrity of ampicillin after the synthesis treatment.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Réactions et propriétés chimiques, Chemical reactions and properties, Modifications chimiques, Chemical modifications, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Acide polymère, Polyacid, Acido polímero, Antiviral, Cellulose ester organique, Cellulose organic ester, Celulosa ester orgánico, Chlorure acyle, Acyl chloride, Cloruro acilo, Cinétique, Kinetics, Cinética, Croissance cristalline en solution, Crystal growth from solutions, Dispersion solide, Solid dispersion, Dispersión sólida, Débenzylation, Debenzylation, Debencilación, Estérification, Esterification, Esterificación, Etude expérimentale, Experimental study, Estudio experimental, Modification chimique, Chemical modification, Modificación química, Polymère vecteur, Control release polymer, Polímero vector, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Préparation, Preparation, Preparación, Ritonavir, Régiosélectivité, Regioselectivity, Regioselectividad, Solution aqueuse, Aqueous solution, Solución acuosa, Vecteur médicament, Drug carrier, Vector medicamento, Inhibiteur cristallisation, Amorphous solid dispersion, Cellulose acylation, Cellulose esters, Cellulose ω-carboxyalkanoates, Crystal growth inhibition, and Oral drug delivery

The use of amorphous solid dispersions (ASDs) is an effective and increasingly widely used approach for solubility enhancement of drugs and drug candidates with poor aqueous solubility. Successful molecular dispersion of drugs in polymer matrices requires new polymers that are designed to meet all ASD requirements, including drug release and prevention of drug recrystallization in storage or from solution. We describe herein design and synthesis of a new series of cellulose ω-carboxyalkanoates for ASDs, by reaction of cellulose with long-chain diacids that have been monoprotected as benzyl esters at one end, and monoactivated as acid chlorides at the other. Glass transition temperatures (Tg) of these cellulose ω-carboxyesters exceed ambient temperature by at least 50 C, providing a sufficient ΔT to prevent drug mobility and crystallization. Cellulose acetate suberates and sebacates prepared in this way are extraordinary solution crystal growth inhibitors for the poorly soluble anti-HIV drug ritonavir. These new cellulose ω-carboxyesters have strong potential as ASD polymers for enhancement of drug solubility and bioavailability.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Analytical chemistry, Chimie analytique, Pharmacology drugs, Pharmacologie, galénique, Pollution, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie analytique, Analytical chemistry, Méthodes chromatographiques et méthodes physiques associées à la chromatographie, Chromatographic methods and physical methods associated with chromatography, Autres méthodes chromatographiques, Other chromatographic methods, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Méthodes de contrôle, Analysis, Inhibiteur recapture, Reuptake inhibitor, Inhibidor recaptura, Sérotonine, Serotonin, Serotonina, Acrylamide dérivé polymère, Acrylamide derivative polymer, Acrilamida derivado polímero, Adsorbant, Adsorbent, Adsorbente, Allylique dérivé copolymère, Allylic derivative copolymer, Alílico derivado copolímero, Analyse chimique, Chemical analysis, Análisis químico, Analyse quantitative, Quantitative analysis, Análisis cuantitativo, Analyse trace, Trace analysis, Análisis huella, Antidépresseur, Antidepressant agent, Antidepresor, Caractérisation, Characterization, Caracterización, Chromatographie HPLC, HPLC chromatography, Cromatografía HPLC, Cinétique, Kinetics, Cinética, Comprimé enrobé, Coated tablet, Tableta cubierta, Condition opératoire, Operating conditions, Condición operatoria, Copolymère greffé, Graft copolymer, Copolímero injertado, Copolymérisation radicalaire, Radical copolymerization, Copolimerización radical, Détecteur UV, Ultraviolet detector, Detector UV, Effet température, Temperature effect, Efecto temperatura, Enrichissement chimique, Chemical enrichment, Enriquecimiento químico, Enrobage entérique, Enteric coating, Cubierta entérica, Extraction SPE, Solid phase extraction, Extracción SPE, Fluvoxamine, Fluvoxamina, Forme libération contrôlée, Controlled release form, Forma liberación controlada, Forme orale, Oral form, Forma oral, Forme pharmaceutique, Dosage form, Forma farmacéutica, Homme, Human, Hombre, Isotherme Freundlich, Freundlich isotherm, Isoterma Freundlich, Isotherme adsorption, Adsorption isotherm, Isotermo adsorción, Libération, Release, Liberación, Liquide biologique, Biological fluid, Líquido biológico, Liquide gastrique, Gastric juice, Jugo gástrico, Liquide intestinal, Intestinal juice, Líquido intestinal, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Microscopie électronique transmission, Transmission electron microscopy, Microscopía electrónica transmisión, Morphologie, Morphology, Morfología, Nanoparticule, Nanoparticle, Nanopartícula, Neurotransmetteur, Neurotransmitter, Neurotransmisor, Particule magnétique, Magnetic particles, Plasma sanguin, Blood plasma, Plasma sanguíneo, Principe actif, Active ingredient, Principio activo, Préparation échantillon, Sample preparation, Preparación muestreo, Préparation, Preparation, Preparación, Psychotrope, Psychotropic, Psicotropo, Sang, Blood, Sangre, Structure surface, Surface structure, Estructura superficie, Séparation magnétique, Magnetic separation, Separación magnética, Enteric drug delivery, Human biological fluids, Magnetic nano-particles, and Pharmaceutical samples

In this research, a novel method is reported for the surface grafting of N-isopropylacrylamide as a thermosensitive agent and 1-(N,N-bis-carboxymethyl)amino-3-allylglycerol with an affinity toward fluvoxamine onto magnetic nano-particles modified by 3-mercaptopropyltrimethoxysilane. The grafted nano-particles were characterized by Fourier transform infrared spectroscopy, elemental analysis, and thermogravimetric analysis. The surface morphology was studied with scanning electron microscopy and transmission electron microscopy. The resulting grafted nano-particles were used in solid phase extraction and determining of trace fluvoxamine in biological human fluids and pharmaceutical samples. The profile of the fluvoxamine uptake by the modified magnetic nano-particles indicated good accessibility of the active sites in the grafted copolymer. It was found that the adsorption behavior could be fitted by the Freundlich adsorption isotherm model. It was observed that a maximum amount of fluvoxamine was released at a temperature above the lower critical solution temperature of the polymer.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Biopolymères de synthèse, Synthetic biopolymers, Polyaminoacides, Aminoacid polymers, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Pharmacologie générale, General pharmacology, Technologie pharmaceutique. Industrie pharmaceutique, Pharmaceutical technology. Pharmaceutical industry, Peptide copolymère, Aminoacid copolymer, Péptido copolímero, Propriété biologique, Biological properties, Propiedad biológica, Amidation, Amidación, Anticancéreux, Antineoplastic agent, Anticanceroso, Aspartique dérivé copolymère, Aspartic derivative copolymer, Aspartico derivado copolímero, Cinétique, Kinetics, Cinética, Concentration critique micellaire, Micellar critical concentration, Concentración crítica micelar, Copolymère biséquencé, Diblock copolymer, Copolímero bisecuencia, Cytotoxicité, Cytotoxicity, Citotoxicidad, Disulfure organique, Organic disulfide, Disulfuro orgánico, Doxorubicine, Doxorubicin, Doxorubicina, Dérivé de l'imidazole, Imidazole derivatives, Imidazol derivado, Effet milieu, Medium effect, Efecto medio, Ethylène oxyde copolymère, Ethylene oxide copolymer, Etileno óxido copolímero, Etude expérimentale, Experimental study, Estudio experimental, In vitro, Internalisation, Internalization, Internalización, Libération, Release, Liberación, Lignée HeLa, Hela cell line, Célula HeLa, Mercaptoalcool, Mercaptoalcohol, Modification chimique, Chemical modification, Modificación química, Nanoencapsulation, Nanoencapsulación, Polymère vecteur, Control release polymer, Polímero vector, Polymérisation ouverture cycle, Ring opening polymerization, Polimerización abertura ciclo, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Préparation, Preparation, Preparación, Réactivité chimique, Chemical reactivity, Reactividad química, Réduction chimique, Chemical reduction, Reducción química, Solution aqueuse, Aqueous solution, Solución acuosa, Solution micellaire, Micellar solution, Solución micelar, Terpolymère, Terpolymer, Terpolímero, Vecteur médicament, Drug carrier, Vector medicamento, Aspartamide dérivé copolymère, Aspartate de benzyle copolymère, Copolymère réductible, and Copolymère sensible stimuli

Novel pH and reduction dual-sensitive biodegradable polymeric micelles for efficient intracellular delivery of anticancer drugs were prepared based on a block copolymer of methyloxy-poly(ethylene glycol)-b-poly[((benzy-L-aspartate)-co-(N-(3-aminopropyl) imidazole-L-aspartamide)] [mPEG-SS-P(BLA-co-APILA), MPBA] synthesized by a combination of ring-opening polymerization and side-chain reaction. The pH/reduction-responsive behavior of MPBA was observed by both dynamic light scattering and UV-vis experiments. The polymeric micelles and DOX-loaded micelles could be prepared simply by adjusting the pH of the polymer solution without the use of any organic solvents. The drug release study indicated that the DOX-loaded micelles showed retarded drug release in phosphate-buffered saline at pH 7.4 and a rapid release after exposure to weakly acidic or reductive environment. The empty micelles were nontoxic and the DOX-loaded micelles displayed obvious anticancer activity similar to free DOX against HeLa cells. Confocal microscopy observation demonstrated that the DOX-loaded MPBA micelles can be quickly internalized into the cells, and effectively deliver the drugs into nuclei. Thus, the pH and reduction dual-responsive MPBA polymeric micelles are an attractive platform to achieve the fast intracellular release of anticancer drugs.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères d'origine naturelle, Natural polymers, Amidon et polyosides divers, Starch and polysaccharides, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Métabolisme général et cellulaire. Vitamines, General and cellular metabolism. Vitamins, Oside polymère, Oside polymer, Osido polímero, Carraghénane, Carrageenan, Carragenano, Cinétique, Kinetics, Cinética, Etude expérimentale, Experimental study, Estudio experimental, Force ionique, Ionic strength, Fuerza iónica, Gélification, Gelation, Gelificación, Hydrogel, Hidrogel, Ion calcium, Calcium ion, Calcio ión, Ion potassium, Potassium ion, Potasio ion, Ion sodium, Sodium ion, Sodio ión, Polyélectrolyte, Polyelectrolyte, Polielectrolito, Relation mise en oeuvre propriété, Property processing relationship, Relación puesta en marcha propiedad, Solution aqueuse, Aqueous solution, Solución acuosa, Synergie, Synergism, Sinergia, Viscoélasticité, Viscoelasticity, Viscoelasticidad, Gel ionotrope, Rhéocinétique, Gel, Polysaccharide, Rheology, and Turbidity

The effect of the addition of calcium or sodium ions on the potassium induced gelation of κ-carrageenan (κ-car) is investigated using oscillatory shear rheology and turbidimetry. Both the gelation kinetics and the steady state shear moduli are investigated. Gelation in mixed salt solutions is compared with that in pure potassium and calcium solutions. It is shown that the elastic shear modulus increases with increasing pure KCl concentration, but decreases with increasing pure CaCl2 concentration. In mixed salts, gelation of K-car is induced by potassium and addition of CaCl2 leads to an increase of the elastic modulus with increasing CaCl2 concentration. κ-Car gelled at low mixed salt concentrations for which it remained liquid in pure salt. At equivalent ionic strengths, the effect of adding NaCl on potassium induced gelation is much weaker. In pure KCl solutions, K-car gels are transparent, but in pure CaCl2 they become increasingly turbid with increasing CaCl2 concentration. The turbidity of gels formed in mixed salts is intermediate.