Erna Turković, Ivana Vasiljević, Milica Drašković, Nataša Obradović, Dragana Vasiljević, and Jelena Parojčić
Pharmaceutics, Vol 13, Iss 468, p 468 (2021)
inkjet printing, printing substrates, mechanical properties, orodispersible films, structured orodispersible film templates, wafer edible sheets, Pharmacy and materia medica, and RS1-441
Inkjet printing is novel approach in drug manufacturing that enables dispensing precise volumes of ink onto substrates. Optimal substrate properties including suitable mechanical characteristic are recognized as crucial to achieve desired dosage form performance upon administration. Identification of relevant quality attributes and their quantification is subject of intensive scientific research. The aim of this work was to explore applicability of different materials as printing substrates and explore contribution of the investigated substrate properties to its printability. Substrates were characterized with regards to uniformity, porosity, disintegration time, mechanical properties and drug dissolution. Experimentally obtained values were mathematically transformed and the obtained results were presented as relevant radar charts. It was shown that structurally different substrates may be employed for orodispersible films inkjet printing. Main disadvantage of single-polymer films was low drug load, and their printability was dependent on film flexibility and mechanical strength. Structured orodispersible film templates exhibited favorable mechanical properties and drug load capacity. Wafer edible sheets were characterized with high mechanical resistance and brittleness which somewhat diminished printability, but did not hinder high drug load. Obtained results provide insight into application of different materials as printing substrates and contribute to understanding of substrate properties which can affect printability.
Mirjana Krkobabić, Djordje Medarević, Nikola Pešić, Dragana Vasiljević, Branka Ivković, and Svetlana Ibrić
Pharmaceutics, Vol 12, Iss 833, p 833 (2020)
three-dimensional (3D) printing, digital light processing (DLP), photopolymerization, photoreactive suspensions, personalized therapy, sustained release, Pharmacy and materia medica, and RS1-441
Three-dimensional (3D) printing technologies are based on successive material printing layer-by-layer and are considered suitable for the production of dosage forms customized for a patient’s needs. In this study, tablets of atomoxetine hydrochloride (ATH) have been successfully fabricated by a digital light processing (DLP) 3D printing technology. Initial materials were photoreactive suspensions, composed of poly(ethylene glycol) diacrylate 700 (PEGDA 700), poly(ethylene glycol) 400 (PEG 400), photoinitiator and suspended ATH. The amount of ATH was varied from 10.00 to 25.00% (w/w), and a range of doses from 12.21 to 40.07 mg has been achieved, indicating the possibility of personalized therapy. The rheological characteristics of all photoreactive suspensions were appropriate for the printing process, while the amount of the suspended particles in the photoreactive suspensions had an impact on the 3D printing process, as well as on mechanical and biopharmaceutical characteristics of tablets. Only the formulation with the highest content of ATH had significantly different tensile strength compared to other formulations. All tablets showed sustained drug release during at least the 8h. ATH crystals were observed with polarized light microscopy of photoreactive suspensions and the cross-sections of the tablets, while no interactions between ATH and polymers were detected by FT-IR spectroscopy.
Solid dispersions were prepared via a solvent evaporation method, employing ethanol (96%, v/v) as solvent, with three different polymers as carrier: povidone, copovidone, and poloxamer 407. Previously developed reversed-phase HPLC (RP-HPLC) methods were modified and used for the simultaneous determination of acetylsalicylic acid and clopidogrel bisulfate and after release from solid dispersions. Chromatography was carried out on a C-18 column, with a mobile phase of acetonitrile–methanol–phosphate buffer pH 3.0, UV detection at 240 nm, and a run time of 6 min. The method was validated according to International Conference of Harmonisation guidelines and validation included specificity, accuracy, precision, linearity, robustness, limit of detection (LOD), and limit of quantification (LOQ). The method is specific for determination of acetylsalicylic acid and clopidogrel bisulfate. The linearity was provided in the concentration range 0.0275–0.1375 mg/mL for acetylsalicylic acid and 0.0200–0.1000 mg/mL for clopidogrel bisulfate, with a correlation coefficient (R2 value) of 0.9999 for both active pharmaceutical ingredients (APIs). Accuracy was confirmed by calculated recoveries for acetylsalicylic acid (98.6–101.0%) and clopidogrel bisulfate (100.0–101.6%). The intra-day and the inter-day precision-calculated relative standard deviations are less than 1%, which indicates high precision of the method. The limits of detection and quantification for acetylsalicylic acid were 0.0004 and 0.0012 mg/mL, and for clopidogrel bisulfate 0.0002 mg/mL and 0.0007 mg/mL, respectively. Small variations in chromatographic conditions did not significantly affect qualitative and quantitative system responses, which proved robustness of method. The proposed RP-HPLC method was applied for simultaneous determination of clopidogrel bisulfate and acetylsalicylic acid from solid dispersions.
Goran Stojanović, Milan Radovanović, Dragana Vasiljević, Tijana Kojić, Bojana Pivaš, Tatjana Puškar, Sunil Kapadia, and Reinhard Baumann
Journal of Sensors, Vol 2019 (2019)
Technology (General) and T1-995
The force is one of the parameters very often measured in our life. Force sensing resistors (FSRs) can be successfully used for measuring force, especially that they can be applied in dentistry for measuring bite forces. However, it is very difficult to apply commercial FSRs for accurate measurement of bite forces and to ensure personalized approach to each patient. Because of that, design, fabrication, and characterization of tailor-made force sensing resistors intended for application in dental medicine are presented in this paper. We designed two FSRs, one with two active areas and one with four active areas (for teeth of higher volume–molars). Two different fabrication processes were applied: first additive, using inkjet printer and silver as material for conductive segments, and second subtractive, using cutter, and gold as a material for manufacturing of interdigitated structure of FSR. Performances of these FSRs have been compared, measuring resistance as a function of applied force, using in-house developed experimental set-up with an articulator.
Marina Odalović, Jelena Parojčić, Dragana Vasiljević, Danijela Đukić Ćosić, and Ljiljana Tasić
Pharmacy, Vol 7, Iss 3, p 92 (2019)
experiential education, interprofessional education, teaching competency development, pharmacy education, Pharmacy and materia medica, and RS1-441
Background: The Erasmus+ project “Reinforcement of the Framework for Experiential Education in Healthcare in Serbia” (ReFEEHS) has been undertaken with the aim to: (i) reinforce and modernize experiential education (ExEd) in the health sciences curricula, (ii) introduce interprofessional education (IPE), and (iii) promote teaching competency development of academic staff and teacher practitioners/clinician educators. The aim of this paper is a post-implementation review of the project activities and outcomes with the emphasis on the impact and sustainability in pharmacy education. Methods: Project Logical framework matrix has been employed as planning, monitoring and evaluation tool which summarizes the main project objectives, project outcomes, relevant activities, indicators of progress, sources of verification, assumptions and risks. Results: The key project outcomes are: (i) update of competency-based curricula and development of quality assurance framework for students professional practice placements; (ii) development and introduction of interprofessional teaching and learning activities through joint curriculum delivery; and (iii) development and implementation of Teaching Certificate in Health Professions Education (TCinHPE) study program. The short-term impact of project activities and outcomes has been assessed based on the feedback received from relevant stakeholders, as well as self-evaluation of participants enrolled in new/updated curricula. Sustainability of project results is necessary in order to achieve long-term impact envisioned as increased level of professional competency of health science students; increased level of teaching competency of academic staff and teacher practitioners; improved patient healthcare and harmonisation with the EU practice and policies. Conclusions: The project outcomes contributed to building capacity at the Serbian universities involved in terms of collaboration between the healthcare professions and, in curriculum and academic staff development. It is expected that improved curricula will positively impact professional competency development of pharmacy students, graduates employability and increased workforce mobility. Meeting the quality standards of the European Higher Education Area will contribute to visibility of Serbian universities and their internationalisation, which is one of the strategic aims of improvement.
Nataša Samardžić, Goran Stojanović, Dragana Vasiljević, and Nikola Jeranče
Sensors, Vol 12, Iss 2, Pp 1288-1298 (2012)
angular position sensor, flexible meander, Kapton film, Chemical technology, and TP1-1185
This paper describes the design, simulation and fabrication of an inductive angular position sensor on a flexible substrate. The sensor is composed of meandering silver coils printed on a flexible substrate (Kapton film) using inkjet technology. The flexibility enables that after printing in the plane, the coils could be rolled and put inside each other. By changing the angular position of the internal coil (rotor) related to the external one (stator), the mutual inductance is changed and consequently the impedance. It is possible to determine the angular position from the measured real and imaginary part of the impedance, in our case in the frequency range from 1 MHz to 10 MHz. Experimental results were compared with simulation results obtained by in-house developed software tool, and very good agreement has been achieved. Thanks to the simple design and fabrication, smaller package space requirements and weight, the presented sensor represents a cost-effective alternative to the other sensors currently used in series production applications.
Manić, Božidar, Tomić, Dragana Vasiljević, and Niković, Ana
Spatium; 2016, Issue 35, p10-21, 12p
CHURCH architecture, ORTHODOX Eastern church buildings, CHURCH building design & construction, ORTHODOX Christianity, and ARCHITECTURE competitions
This paper focuses on the architectural competitions for Orthodox Christian churches in Serbia since 1990, both on the analysis of the designs submitted and the competition requirements. The first competition for an Orthodox church in Serbia after World War II was announced for Priština in 1991. After that, competitions for the temple in Čukarica, Novi Beograd, Niš, Aleksinac and Kruševac were conducted. Thanks to the fact that architectural competitions allow a greater degree of creative freedom to the architects than regular practice, various solutions were offered, from replicas of models from architectural history and tradition to fully non-traditional proposals. Depending on the relationship to tradition, architectural design approaches can be classified into three main groups: radically modernizing, conservatively traditionalist, and compromising. Of the six competitions conducted, four churches were built, which are among the most architecturally successful newer churches in Serbia. This points to the importance of the implementation of the architectural competition in this field of architecture. The diversity of the award-winning projects shows that there is awareness of the possibility for the further development of church architecture, favouring a moderate approach. [ABSTRACT FROM AUTHOR]