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CHITOSAN, AGAR, FOOD packaging, PLASTIC scrap, PACKAGING film, FOOD waste, and HYDROGEN bonding

Packaging is a crucial tool for reducing food waste and enhancing product competitiveness. Fossil fuel-based plastics, mostly used for food packaging, account for nearly 40% of global plastic waste. To address this issue, this study developed a layer-by-layer casting technique to create novel bilayered plastic composites with distinct agar/chitosan and PVA/agar layers. Film's properties, such as thickness, plasticity, and tensile strength, were affected by adjusting the volume of the layers. The elongation at break was positively related to the presence of citric acid (up to 30 wt%) as a crosslinker. The chitosan-rich first layer provided better UV-light blocking potential and opacity, which were beneficial in the prevention of lipid oxidation. Increasing the second layer by 40–60% substantially reduced the light absorption, while the colors were proportional to the citric acid content. The FT-IR band at 1713 cm−1 indicated an increase in C=O ester groups with crosslinker content. The hydrophobicity of the films was enhanced by the chitosan-rich layer. XRD supported intramolecular and intermolecular hydrogen bonding, whereas the micrographs revealed tightly bound structure between layers. The results corroborated that the inclusion of agar in the formulations increased the stability of the film, making it ideal for various packaging applications. [Display omitted] • A layer-by-layer casting was used to develop films made up of agar-chitosan covered with a citric acid-crosslinked agar/PVA. • The physico-mechanical properties of the double layered films were affected by the different layers' formulations. • FT-IR and XRD supported molecular hydrogen bonding, and micrographs revealed tightly bound structure between layers. • Including agar in layers' formulations increased the stability and suitability of the film for packaging applications. • The higher hydrophobicity of the bilayer films could increase their potential use in the packaging of various food products. [ABSTRACT FROM AUTHOR]

COOPERATIVE binding (Biochemistry), PYRROLES, CHOLINE chloride, DENSITY functional theory, and ULTRAVIOLET-visible spectroscopy

• Synthesis and anion binding studies of meso- one walled cyanophenyl extended C4P have been described. • BindFit and DFT studies have revealed 1:1 anion binding stoichiometry. • Maximum anion binding affinity was observed in case of fluoride ion. • Conformational change from 1,3-alternate to cone in the presence of anion has been confirmed by 1H-NMR. • NH-hydrogen bonding and anion-π interactions cooperatively govern anion binding. A novel one-walled meso -cyanophenyl functionalized calix[4]pyrrole (4) was synthesized from cyanophenyl appended dipyrromethane (3) through conventional strategy and also by utilizing deep eutectic solvent of N,N' -dimethyl urea (DMU) & L -(+)-tartaric acid (TA) in a ratio of 7:3. The structural confirmation of 4 was done through 1H-NMR, 13C-NMR, FT-IR, and HRMS spectral data. Anion binding studies of the receptor 4 with several anions (halides, trigonal oxoanions, tetragonal oxoanions, etc.) used as tetrabutylammonium (TBA) salts, were successfully investigated by virtue of UV–Vis spectroscopy and time dependent density functional theory (TD-DFT). Notably, the UV–Vis absorbance titrations performed in CH 3 CN solvent, revealed significantly higher anion binding of receptor 4 with F¯, Cl¯, Br¯, and SCN¯ in comparison to the simple C4P. This can be ascribed to the fact that the cyanophenyl moiety is π-acidic in nature which participates in anion complexation through weak anion-π interactions (observed through 1H-NMR spectroscopy) and hence modulates anion binding through cooperative effect of preliminary NH-hydrogen bonding due to C4P scaffold and anion-π contacts due to cyanophenyl moiety. [Display omitted] [ABSTRACT FROM AUTHOR]

MULTIPLE Signal Classification, BIOMOLECULES, NUCLEAR magnetic resonance spectroscopy, MUSICAL pitch, HORMONES, and AMINO acids

In this work, we have performed an alternative analytical process including the transformation of few biological molecules' frequencies data obtained by 13CNMR spectroscopy into sounds characterized with their frequencies, intensities, and time durations. As a main point, we have relied on the "magnetic behavior of proton" as a positively charged species in the nucleus to measure the nucleus relaxation time and frequency domains. This proposal is examined for human beta-globin sequences using only "α-carbon" of their containing amino acids. Similarly, "all 23 kinds of carbon atoms in the Leu- and Met-enkephalins" as hormones have been studied and converted to musical data using time–frequency MUSIC algorithm (TFMusic-A) in which Max/MSP program is used for musical conversions. The results show that the TFMusic-A might be a proper candidate and primarily a creative symbolic method for fundamental unity between the natural ordered structure of life and humans. [ABSTRACT FROM AUTHOR]

PHOSPHINE oxides, ARYL iodides, ARYLATION, ALKOXY group, ASYMMETRIC synthesis, ACID derivatives, METHOXY group, CLINICAL chemistry, and SONOGASHIRA reaction

Keywords: phosphinates; P-stereogenic centers; nickel catalysis; cross-coupling; asymmetric catalysis EN phosphinates P-stereogenic centers nickel catalysis cross-coupling asymmetric catalysis 1819 1823 5 08/29/23 20230915 NES 230915 Graph P-Stereogenic organic phosphorus compounds, especially chiral phosphinic acid derivatives, are useful in medicinal chemistry, pesticide chemistry, organic materials science, and biochemistry. Moreover, when we employed aryl iodides with a free amino ( B 26 b ) or hydroxy group ( B 27 b ) at the I para i -position of the aryl ring, P-chiral phosphinates were obtained in moderate yields (71 and 68%) and high ee values (88 and 81% ee). [41] However, we found aryl iodides with different electronic properties all gave the corresponding P-chiral phosphinates with moderate to high ee values (62-82% ee); in other words, the enantioselectivity was only slightly affected by the electronic properties of the aryl iodides. During the preparation of our manuscript, Duan and our group separately reported Ni(0)-catalyzed intermolecular reactions of nonactivated aryl halides [39] and Ni(II)-catalyzed intermolecular reactions of heterocyclic halides, [40] respectively. [Extracted from the article]

MACHINE learning, ARTIFICIAL intelligence, DRUG discovery, CHEMOMETRICS, EXPERT systems, and DRUG synthesis

Chemometrics and machine learning are artificial intelligence-based methods stirring a transformative change in chemistry. Organic synthesis, drug discovery and analytical techniques are incorporating machine learning techniques at an accelerated pace. However, machine-assisted chemistry faces challenges while solving critical problems in chemistry due to complex relationships in data sets. Even with increasing publishing volumes on machine learning, its application in areas of chemistry is not a straightforward endeavour. A particular concern in applying machine learning in chemistry is data availability and reproducibility. The present review article discusses the various chemometric methods, expert systems, and machine learning techniques developed for solving problems of organic synthesis and drug discovery with selected examples. Further, a concise discussion on chemometrics and ML deployed in analytical techniques such as, spectroscopy, microscopy and chromatography are presented. Finally, the review reflects the challenges, opportunities and future perspectives on machine learning and automation in chemistry. The review concludes by pondering on some tough questions on applying machine learning and their possibility of navigation in the different terrains of chemistry. [ABSTRACT FROM AUTHOR]

HYDROXYLATION, TITANIUM, HYDROGEN peroxide, EPOXIDATION, and KETONES

The titanium complex of the cis‐1,2‐diaminocyclohexane (cis‐DACH) derived Berkessel‐salalen ligand is a highly efficient and enantioselective catalyst for the asymmetric epoxidation of terminal olefins with hydrogen peroxide ("Berkessel‐Katsuki catalyst"). We herein report that this epoxidation catalyst also effects the highly enantioselective hydroxylation of benzylic C−H bonds with hydrogen peroxide. Mechanism‐based ligand optimization identified a novel nitro‐salalen Ti‐catalyst of the highest efficiency ever reported for asymmetric catalytic benzylic hydroxylation, with enantioselectivities of up to 98 % ee, while overoxidation to ketone is marginal. The novel nitro‐salalen Ti‐catalyst also shows enhanced epoxidation efficiency, as evidenced by e.g. the conversion of 1‐decene to its epoxide in 90 % yield with 94 % ee, at a catalyst loading of 0.1 mol‐% only. [ABSTRACT FROM AUTHOR]

LIGNIN structure, LIGNINS, COVALENT bonds, MOLECULAR weights, SUSTAINABLE development, PETROLEUM, and DEPOLYMERIZATION

Lignin holds tremendous and versatile possibilities to produce value-added chemicals and high performing polymeric materials. Over the years, different cutting-edge lignin depolymerization methodologies have been developed, mainly focusing on achieving excellent yields of mono-phenolic products, some even approaching the theoretical maximum. However, due to lignin's inherent heterogeneity and recalcitrance, its depolymerization leads to relatively complex product streams, also containing dimers, and higher molecular weight fragments in substantial quantities. The subsequent chemo-catalytic valorization of these higher molecular weight streams, containing difficult-to-break, mainly C–C covalent bonds, is tremendously challenging, and has consequently received much less attention. In this minireview, we present an overview of recent advances on the development of sustainable biorefinery strategies aimed at the production of well-defined chemicals and polymeric materials, the prime focus being on depolymerized lignin oils, containing high molecular weight fractions. The key central unit operation to achieve this is (bio)catalytic funneling, which holds great potential to overcome separation and purification challenges. [ABSTRACT FROM AUTHOR]

MOLECULAR structure, CHEMICAL properties, COORDINATE covalent bond, COORDINATION polymers, HYDROGENATION, POLYMERS, ORGANIC synthesis, and ELECTRONIC structure

• Molecular properties, i.e. physical and chemical properties, are affected by the functional groups attached to them. • Phosphinidines have been demonstrated to be highly effective in a variety of cases such as polymer chemistry, organic synthesis for the preparation of polyphosphanes, coordination chemistry, and more recently in catalysis as ligands in cross-coupling reactions. • Various types of metal ions and the ancillary ligands existing in the reaction determine the nature of the created products. ligands have crucial impact on the region-, chemo-, and, of course, stereoselectivity in metal- catalytic processes. [ABSTRACT FROM AUTHOR]

RING-opening polymerization, ACETAL resins, COPOLYMERS, BLOCK copolymers, POLYMERIZATION, MONOMERS, and POLYMERS

Radical Ring‐opening polymerization (RROP) of cyclic ketene acetals (CKAs) emerges to be a valuable polymerization technique. In attracting more attention, RROP has seen a new spike in publications, which the authors will put into perspective. This review will hence address the progress made on the number of available CKAs and the synthetic strategies to get them. In grouping, the available monomers into distinct categories, the enormous variety of available CKAs will be highlighted. Polymerizations of CKAs without vinylenes have the potential to yield fully biodegradable polymers, which is why this kind of polymerization is the focus of this review. Detailing the current understanding of the mechanism, the various side reactions will be noted and also their effect on the overall properties of the final polymers. Current attempts to control the ring‐retaining and branching reactions will be discussed as well. In addition to the polymerization itself, the available materials will be discussed as well as homopolymers, copolymers of CKAs, and block‐copolymers with pure CKA‐blocks have significantly widened the range of possible applications of materials from RROP. Altogether this review highlights the progress in the entire field of RROP just of CKAs to give a holistic overview of the field. [ABSTRACT FROM AUTHOR]

MOLECULAR size, MICROFLUIDICS, POLYDIMETHYLSILOXANE, OVERHAUSER effect (Nuclear physics), SUPRAMOLECULAR chemistry, NUCLEAR magnetic resonance spectroscopy, HYDROGELS, and POLYACRYLAMIDE

The integration of microscopic hydrogels with high specific surface area and physically reactive groups into microfluidic systems for selective molecular interactions is attracting increasing attention. Herein, the reversible capture and release of molecules through host–guest interactions of hydrogel dots in a microfluidic device is reported, which translates the supramolecular chemistry to the microscale conditions under continuous flow. Polyacrylamide (PAAm) hydrogel arrays with grafted β‐cyclodextrin (β‐CD) modified poly(2‐methyl‐2‐oxazoline) (CD‐PMOXA) chains are fabricated by photopolymerization and integrated into a polydimethylsiloxane (PDMS)‐on‐glass chip. The β‐CD/adamantane (β‐CD/Ada) host–guest complex is confirmed by two dimensional Nuclear Overhauser Effect Spectroscopy NMR (2D NOESY NMR) prior to transfer to microfluidics. Ada‐modified molecules are successfully captured by host–guest interaction formed between the CD‐PMOXA grafted chains in the hydrogel network and the guest molecule in the solution. Furthermore, the captured molecules are released by perfusing free β‐CD with higher binding affinity than those grafted in the hydrogel array. A small guest molecule adamantane‐fluorescein‐isothiocyanate (Ada‐FITC) and a macromolecular guest molecule (Ada‐PMOXA‐Cyanine 5 (Cy5)) are separately captured and released for three times with a release ratio up to 46% and 92%, respectively. The reproducible capture and release of functional molecules with different sizes demonstrates the stability of this hydrogel system in microfluidics and will provide an opportunity for future applications. [ABSTRACT FROM AUTHOR]

ISOTHERMAL titration calorimetry, MALACHITE green, ENZYME kinetics, SUPRAMOLECULAR chemistry, MASS spectrometry, and INFRARED spectroscopy

Alkaline phosphatase (AP) enzymes are of broad interest in fields ranging from biochemistry and medicine to biotechnology and nanotechnology. Characterising the catalytic activity of AP is typically realised by either employing non‐natural signal‐generating substrates that are detectable by absorbance and fluorescence spectroscopy or by quantifying the release of inorganic phosphate by the classic malachite green assay. The latter method is often required for studying "spectroscopically silent" biomolecular substrates, but it does not enable continuous monitoring of kinetics in real‐time. In recent years, newer techniques for studying AP function have been developed to circumvent this limitation, including fluorescent and colourimetric substrate‐specific assays based on supramolecular chemistry, organic probes and nanomaterials, as well as other assays based on isothermal titration calorimetry, direct detection with infrared spectroscopy and mass spectrometry, and monitoring conformational change by fluorescent nanoantennas. Here, we review these strategies and comment on their strengths and weaknesses in the context of AP. [ABSTRACT FROM AUTHOR]

ANTI-infective agents, SULFONYL chlorides, STREPTOCOCCUS pyogenes, HYDROXY acids, BACILLUS pumilus, ACETYL chloride, CARBAMATE derivatives, OXAZOLIDINONES, and AMIDES

In the present work, a series of novel oxazolidinone derivatives containing thieno-pyridine ring system (11a–n) were synthesized in six steps. Synthesis of amino oxazolidinone scaffold (10) involved nucleophilic substitution of thienopyridine (4) with P-chloro-nitrobenzene (3) in dimethyl formamide at 65 °C give nitro compound (5) which was further reduced in catalytic hydrogenation condition using Raney-Nickel in isopropyl alcohol afforded amine (6). Reaction of compound (6) with 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione (7) at mild reflux condition in isopropyl alcohol gives compound (8). Hydroxy amine compound (8) further undergo carbonyl insertion reaction with 1, 1'-carbonylbis(1H-imidazole) afforded oxazolidinone compound (9). The de-protection of phthalamide group of compound (9) carried by treating with aqueous solution of hydrazine hydrate in methanol at room temperature give compound (10). Finally, compound (10) reacts with acetyl chloride, carboxylic acid, sulfonyl chloride and chloro format by customary method provided amides, sulfonamide and carbamate derivative of (5S)-5-(aminomethyl)-3-[4-(6,7-dihydrothieno[3,2-c]pyridin-5(4H)-yl)phenyl]-1,3-oxazolidin-2-one. The developed synthetic approach was operationally simple and high yielding. The structures of the synthesized compounds were elucidated by IR, MS, 1H and 13C-NMR. Synthesized compounds (11a–n) were tested for antibacterial activity against a panel of Gram-positive bacteria comprising Staphylococcus aureus (ATCC5638), Streptococcus pyogenes (ATCC12344), Bacillus subtilis (ATCC6051), Bacillus pumilus (ATCC27142), and Enterococcus faecalis (NCIM5253). The investigation of antimicrobial screening data revealed that, most of the compounds tested have demonstrated sensible to good bacterial activity. In summary, preliminary results of activity indicate that, acetyl derivative (11a), methane sulfonamide derivative (11c) and p-toluene sulfonamide derivative (11e) found to be good activity and di-(methane sulfonamide) derivative (11d) showed comparable activity to reference drug substances. [ABSTRACT FROM AUTHOR]

GENTIAN violet, SCHIFF bases, BASIC dyes, AQUEOUS solutions, COMPUTATIONAL chemistry, EXOTHERMIC reactions, ADSORPTION kinetics, PORE size distribution, and COLOR removal in water purification

• New bis(pyrano[3,2- c ]quinolinone) based on Schiff base was prepared. • The synthesized adsorbent was characterized using several techniques. • The batch adsorption technique toward cationic dye was applied. • The adsorption kinetics, isotherms, recyclability and Thermodynamic parameters were calculated. • The primary adsorption mechanism was confirmed by computational chemistry. Organic compound water pollution is one of the difficult environmental issues facing the advancement of human civilization. So, New bis(pyrano[3,2- c ]quinolinone) based on Schiff base adsorbent was prepared to participate in solving this problem. The synthesized adsorbent was characterized using FT-IR, 1H NMR, XRD, SEM, elemental analysis, N 2 - adsorption-desorption isotherm, S BET , and Pore size distribution studies. The obtained results revealed a significant improvement in the new schiff base surface texture and crystallinity. Further, pH zpc of the new adsorbent has been examined to be 3.7. Its decolorization efficiency toward methylene blue (MB) dye from an aqueous solution was examined. Also, the factors of pH, contact time, reaction temperature, and initial dye concentration were optimized. Overall, this study emphasized that the newly synthesized Schiff base act as an effective adsorbent (99%) at a very short time (5 min., 10 ppm dye concentration, pH = 9 and temperature = 25 °C) and can be regenerated for five cycles for the removal of MB dye from aqueous solutions. Freundlich isotherm model and pseudo-second order kinetic model were fit effectively for the MB dye adsorption experimental data. Also, the calculated thermodynamic parameters revealed a spontaneous and exothermic adsorption reaction. FT- IR study and computational chemistry study proved that the decolorization interaction mechanism between the positive (- N +) sites of MB dye and the negative (- OH) active sites of the new Schiff base adsorbent at the optimum conditions occurred as a physisorption process. [Display omitted] [ABSTRACT FROM AUTHOR]

CELL imaging, PROTISTA, DRUG target, LUMINOPHORES, QUANTUM wells, and PLASMODIOPHORA brassicae

A library of eight different cationic emitters with emission properties in solution and in solid‐state (solution and solid‐state emitters – SSSE) is presented. These compounds, bearing either ammonium or pyridinium groups, have been investigated regarding their photophysical properties as well as their potential application in biological imaging. Besides high quantum yields as well as a high degree of stability during the imaging process, it was additionally revealed that a broad range of biological targets can be addressed, such as different bacterial strains, human cells as well as protists. The reported SSSE approach employing the mentioned robust emitters for biological imaging, will contribute to a rapid and facile way to design and apply affordable emitters with outstanding properties. Additionally, these emitters will overcome the drawbacks of classical luminophores and agents featuring well‐known aggregation‐induced emission (AIE) or aggregation‐caused quenching (ACQ) properties. [ABSTRACT FROM AUTHOR]

HETEROGENEOUS catalysts, FERRIC oxide, CATALYST synthesis, HEMATITE, FOURIER transform infrared spectroscopy, FIELD emission electron microscopy, AROMATIC aldehydes, and CATALYSTS recycling

• First time report on the synthesis of Fe 2 O 3 nanorods (NRs) by a green process via a mixture of Eucalyptus citriodora and Murraya koenigii leaf extracts. • XRD, FESEM, EDX, FTIR, UV-DRS, BET, and VSM analysis confirmed the biosynthesis of Fe 2 O 3 NRs. • Fe 2 O 3 NRs exhibited excellent catalytic performance for the Biginelli reaction. • The synthesized catalyst exhibited high stability, reusability, an excellent yield of Biginelli products, and easy workup. For the first time, mixed-phase (Hematite and Maghemite) magnetic Fe 2 O 3 nanorods were successfully biosynthesis by sol-gel auto-combustion method using the 1:1 mixture of Eucalyptus citriodora and Murraya koenigii leaf extract as a capping agent, and its catalytic effect on synthesis of 6-(chloromethyl)-1,2,3,4-tetrahydro-2-pyrimidinone (THPMs) derivatives were investigated. Further, the phase formation, surface topography, and crystallinity of biosynthesized Fe 2 O 3 nanorods (NRs) were explored using powder XRD (X-Ray Diffraction), UVDRS (UV–Visible Reflectance Spectroscopy), FTIR (Fourier Transform Infrared Spectroscopy), FESEM (Field Emission Scanning Electron Microscopy), EDX (Energy Dispersive X-Ray), and VSM (Vibrating Sample Magnetometry). Furthermore, the catalytic activity of biosynthesized Fe 2 O 3 NRs (C1, C2, and C3) was examined for one-pot synthesis of ethyl 6-(chloromethyl)-1,2,3,4-tetrahydro-2-oxo-4-arylpyrimidine-5-carboxylate via Biginelli reaction. To achieve high yields (93–99 %) of 6-(chloromethyl)-1,2,3,4-tetrahydro-2-pyrimidinone derivatives, this heterogeneous catalytic method is used with a wide range of aromatic aldehydes within a minimum reaction time, simple reaction work-up, and easily recoverable catalyst by an external magnet. The recovered catalyst is then employed for five successive cycles without non-noticeable loss of catalytic activity. We believe that this protocol presents a broad scope for Biginelli reaction through greenly produced and magnetically separable heterogeneous catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

INDOLE compounds, INDOLE derivatives, INDOLE, AMINATION, LSD (Drug), PHENYLENEDIAMINES, TRANSITION metal catalysts, ORGANIC chemistry, and ORGANIC acids

B. Acid-catalyzed indole synthesis An efficient one-pot synthesis of I N i SB 1 sb -substituted indole derivatives ( B 15 b ) was reported by Kutznetsov and colleagues[45]. I. Important methods for indole synthesis Numerous methods for the synthesis of indoles are cited in the literature (Figure 2).[7],[8],[25]Table 2 highlights a few important classical methods for the synthesis of indoles. Recently, there has been increased interest in metal-free indole synthesis as compared to classical metal-assisted indole syntheses. Transition metal-free indole synthesis The synthesis of indoles can be accomplished through special reaction types and routes. [Extracted from the article]

TERPENES, ALKENES, METHYLATION, DITERPENES, PROTON transfer reactions, METHYLTRANSFERASES, and CARBOCATIONS

Terpenoids are built from isoprene building blocks and have numerous biological functions. Selective late‐stage modification of their carbon scaffold has the potential to optimize or transform their biological activities. However, the synthesis of terpenoids with a non‐natural carbon scaffold is often a challenging endeavor because of the complexity of these molecules. Herein we report the identification and engineering of (S)‐adenosyl‐l‐methionine‐dependent sterol methyltransferases for selective C‐methylation of linear terpenoids. The engineered enzyme catalyzes selective methylation of unactivated alkenes in mono‐, sesqui‐ and diterpenoids to produce C11, C16 and C21 derivatives. Preparative conversion and product isolation reveals that this biocatalyst performs C−C bond formation with high chemo‐ and regioselectivity. The alkene methylation most likely proceeds via a carbocation intermediate and regioselective deprotonation. This method opens new avenues for modifying the carbon scaffold of alkenes in general and terpenoids in particular. [ABSTRACT FROM AUTHOR]

ALKENES, METHYLATION, and AMINO acid sequence

A variant with three changes in the amino acid sequence was able to produce methylated derivatives of linear terpenoids with high selectivity by C-methylation of an unactivated alkene. Cover Picture: Methylation of Unactivated Alkenes with Engineered Methyltransferases To Generate Non-natural Terpenoids (Angew. Keywords: Alkene Methylation; Biocatalysis; Late-Stage Modification; Methyltransferase; Terpenoids EN Alkene Methylation Biocatalysis Late-Stage Modification Methyltransferase Terpenoids 1 1 1 06/20/23 20230626 NES 230626 B A methyltransferase b from the green alga I Chlamydomonas reinhardtii i was identified and engineered for late-stage modifications of the carbon skeleton of terpenes. [Extracted from the article]

SOLID phase extraction, PULMONARY surfactant, ANALYTICAL chemistry, SURFACE active agents, PREMATURE infants, and DENSITY functional theory

• A mixed mode DSPE approach was developed using organic polymers. • The method was used to lung surfactants determination in EBC samples. • Density functional theory calculations were used to show the nature of the chemical interactions. • Simplex centroid experimental design was used for optimization of the sorbent composition. A mixed mode dispersive solid phase extraction method was introduced for the extraction of three lung surfactants from exhaled breath condensate samples. Considering the trends to green analytical chemistry, organic polymers including polystyrene (PS), polymethylmethacrylate (PMMA-15 K), and polymethylmethacrylate (PMMA-45 K) were utilized as the sorbent for extraction of the analytes. The extraction capability for each polymer toward the studied analytes was evaluated using simplex centroid design. Based on the results, a mixture of sorbents consisting of PS, PMMA-15 K, and PMMA-45 K mixture with the mass ratio of 1:2:1: w/w/w was selected as the suitable sorbent. The effective parameters influencing the method's efficiency were investigated and optimized. Based on the figure of merit for the developed method, the calibration curves were linear in the concentration range of 0.76–1000 ng mL–1 and limits of detection were from 0.09 to 0.19 ng mL–1. The method repeatability was investigated at three concentrations as inter- and intra-day precisions and the obtained data showed that they were in the ranges of 5.2–9.1 and 4.2–8.9%, respectively. The enrichment factors were in the range of 88–100. The developed method was successfully employed in the analysis of the surfactants in the exhaled breath samples of three premature infants collected from the expiratory circuits of the mechanical ventilators. The nature of the chemical interactions with PMMA-PS complex system of the surfactants was investigated through Density Functional Theory calculations. Calculated binding energies showed that PMMA-PS complex system exhibit high performance in the extraction of lung surfactants. The most powerful interaction is between PMMA-PS complex system and 1-palmitoyl-2-oleoylsn‑glycero-3-phosphocholine. [ABSTRACT FROM AUTHOR]