Journal of the Serbian Chemical Society

Voltammetric study of a detergent-stable Actinomadura keratinilytica lipase CPT29-cross-linked GA/BSA platinum biosensor

2026-06-01T12:52:34+02:00

This study describes the immobilization of a native lipase (LCPT29) from Actinomadura keratinilytica strain CPT29 isolated from poultry compost in the northeast of Algeria in order to detect ester pollutants in an aqueous environment. For this purpose, this detergent-stable lipase was immobilized with glutaraldehyde as a cross-linker, in the presence of bovine serum albumin (BSA) onto a platinum (Pt) electrode. The prepared enzyme membrane was characterized by FT-IR spectroscopy, confirming its network formation, while its coating of the Pt-electrode was evaluated using cyclic voltammetry. The effectiveness of the cross-linked enzyme membrane-coated working electrode was evaluated electrochemically by detecting propyl 4-hydroxybenzoate (PHB) as a model analyte. Under optimal conditions and at an applied potential of –250 mV vs. Ag/AgCl, the LCPT29-based biosensor showed a linear response over the concentration range from 10^-14 to 10^-8 mol L^-1 (r = 0.991), with a detection limit of 10-14 mol L^-1. The biosensor exhibited high sensitivity (0.0327 mA L mol^-1), good stability (RSD = 0.37 %) and significant selectivity as well as the ability to analyse trace amounts of PHB in real water samples, demonstrating its potential for electrochemical biosensing applications.

The significance of chemistry curriculum for educational profiles in secondary medical vocational education

2026-07-10T12:42:08+02:00

Investment in fundamental chemical research represents a key factor in the advancement of healthcare, which is increasingly facing the challenges of modern society. Nevertheless, the importance of chemistry in medical education is often insufficiently recognized, resulting in a weak connection between theoretical and practical aspects of instruction. Numerous studies highlight the need for a deeper integration of chemical content into vocational medical subjects. This paper analyses the attitudes of vocational subject teachers in secondary medical schools regarding the impact of chemistry curriculum reform on the quality and effectiveness of vocational instruction. The research was conducted using a descriptive method and an anonymous questionnaire on a sample of 73 teachers from medical schools across the Republic of Serbia. The findings indicate the importance of chemistry education for vocational medical training and suggest the need for improved curricular integration in secondary medical schools. These findings may serve as guidelines for the development of educational policies in the field of vocational education.

Design of novel quinazoline-chalcone hybrids as potent epidermal growth factor receptor inhibitors

2026-08-12T16:58:16+02:00

This study successfully designed and synthesized a novel series of quinazoline–chalcone hybrids. The key innovation lies in the molecular hybridization of the pharmacophoric quinazoline scaffold with a chalcone moiety, creating new chemical entities to exploit potential synergistic antitumor effects. A concise multi-step synthetic route was efficiently implemented. Preliminary evaluation demonstrated that a majority of these hybrids exhibited potent antiproliferative activity against non-small cell lung cancer (NSCLC) cell lines (A549 and H1975) in vitro. Molecular docking studies suggested against epidermal growth factor receptor (EGFR) inhibition as a potential mechanism, with the compounds forming stable interactions with the kinase domain. Furthermore, in silico absorption, distribution, metabolism and excretion (ADME) and toxicity predictions by SwissADME and ProTox 3.0, respectively, indicated promising drug-like properties and safety profiles. However, the cytotoxicity was assessed only on cancer cell lines, and the selectivity against normal cells remains to be determined. Despite this limitation, the compelling initial results position these novel hybrids as promising leads for future optimization and development.

Green extraction and valorization of olive pomace using limonene: A kinetic modeling and thermodynamic approach

2026-07-13T10:57:00+02:00

This work explores the extraction of oil from olive pomace using limonene as a green solvent, with particular emphasis on the effects of temperature on yield, kinetics and thermodynamics. Results show that oil recovery increases with time and temperature, following a two-stage mechanism: a rapid washing phase dominated by surface oil removal and a slower diffusion-controlled stage. Kinetic modeling show that the Patricelli model best fits the process (R² > 0.99), while mass transfer coefficients confirm the predominance of washing at lower temperatures. The relatively low activation energy (16.98 kJ·mol^-1) suggests a diffusion-limited process that is thermally accessible and suitable for industrial application. Thermodynamic parameters support this interpretation, with negative Gibbs energy change confirming spontaneity, an endothermic enthalpy change (ΔH = 1.68 kJ·mol^-1), and a positive entropy change (ΔS = 17.39 J·mol^-1·K^-1) reflecting increased molecular disorder during extraction. Overall, limonene demonstrates high efficiency and sustainability, offering a viable alternative to hexane in line with green chemistry principles.

Advanced polypropylene random copolymer nanocomposites: Effect of natural bentonite clay and aluminum hydroxide on morphology and properties

2026-06-24T01:44:54+02:00

This paper examines the influence of nanoparticles of the natural mineral bentonite and aluminum hydroxide in obtaining nanocomposites that are based on a compatibilized polypropylene random copolymer. A random copolymer of ethylene and propylene modified with maleic anhydride was used as a compatibilizer. The total amount of filler introduced into the polypropylene random copolymer composition was 50 wt. %. To study the synergistic effect, using a mixture of fillers, bentonite was included in the formulation at five different concentrations (5, 10, 15, 20 and 25 wt. %). The composites were obtained by mechanical mixing in the melt of a compatibilized polymer matrix. The structural, morphological, physical-mechanical, thermal properties and fire resistance of the obtained composite materials were determined. The structural and morphological properties were characterized using infrared spectroscopy (IR) and scanning electron microscopy. Based on the results of IR and scanning electron microscopy-energy dispersive X-ray spectra, the presence of elements and bonds corresponding to the composition of bentonite and aluminum hydroxide, which were used as fillers in the composition of the polypropylene random copolymer, was confirmed. Morphological study revealed minor agglomerates of bentonite nanoparticles. Thermal properties of the obtained composites were determined using thermogravimetric analysis and differential scanning calorimetry. Thermogravimetric analysis showed that the addition of bentonite increases the thermal stability of composites, as evidenced by a decrease in the rate of mass loss. Mechanical properties (tensile strength, elongation at break) decrease with increasing bentonite concentration. The synergistic effect obtained by the combined use of aluminum hydroxide and bentonite was manifested mainly in an increase in the melt flow index of the composite. The sample containing 25 wt. % natural bentonite showed the highest melt flow index values, up to 3.12 g/10 min.

Synthesis, structure and photocatalytic properties of a novel chromium compound constructed from N-substituted acetic acid and nitrogen-containing ligands

2026-06-25T14:57:30+02:00

In this study, a novel Cr(III)-based coordination compound, namely [Cr(L)(phen)(COO)]₂∙6H₂O (1), [H2L: 3-carboxy-1-(carboxymethyl)-2-oxidopyridinium, phen: 1,10-phenanthroline], was successfully synthesized via a solvothermal method. The structure of the synthesized coordination compound was confirmed by CCD single-crystal X-ray diffraction. The compound was further characterized using infrared spectroscopy, UV–Vis spectroscopy, thermogravimetric analysis and powder X-ray diffraction. The degradation of tetracycline (TC) was investigated using the coordination compound in combination with H₂O₂ under simulated ultraviolet (UV) light. Detailed catalytic reaction and kinetic studies revealed a TC degradation efficiency of 82.99 % with a rate constant of 0.0115 min^-1, indicating that the coordination compound exhibits promising performance in the photocatalytic degradation of antibiotics.

Phenolic compounds adsorption from olive oil industry effluent using experimental design methodology: screening and central composite design optimization

2026-05-07T19:51:13+02:00

The experimental design methodology was investigated to model and optimize the adsorption process for removing phenolic compounds (PC) from olive mill wastewater (OMW) using magnesium–aluminum layered double hydroxide (LDH). The LDH powders were synthesized by the co-precipitation method. The structural, textural and morphological characterizations were performed. To evaluate quickly and effectively the effects of five parameters (initial PC content, contact time, solid/liquid ratio, initial pH and temperature) on the adsorption efficiency, a Hadamard matrix was employed for screening. Subsequently, a central composite design was utilized to optimize the adsorption process based on four key parameters. The correlation coefficient for the polynomial model was found to be 94 %. Predicted values generated from the response function matched the experimental data closely, indicating a good agreement. Under the selected optimal conditions, a maximum PC removal efficiency of 80.85 % was achieved. The reusability of the regenerated LDH by calcination at 500 °C in the adsorption process was assessed over four consecutive runs under the selected optimal conditions. The removal percentages of PC and chemical oxygen demand indicated that calcined LDH could be a viable alternative for treating OMW.

Correction of author’s name in the article: Bimetallic polyaniline/silver–palladium nanocomposite for rapid and sustainable degradation of eosin yellow dye from wastewater

2026-09-10T22:16:52+02:00

Efficient one-pot solvothermal synthesis of lanthanum–iron oxide and its application in tenofovir adsorption

2026-04-14T09:56:50+02:00

Novel magnetic lanthanum-iron oxide composites have been synthesized using a one-pot method. The proposed approach simplifies the synthesis process by eliminating traditional requirements such as pH adjustment and high-temperature calcination, resulting in a more streamlined procedure and the production of a magnetic material. The effects of the Fe-to-La ratio, reaction time, and reaction temperature on the properties and adsorption performance of the lanthanum–iron oxide composites were investigated. The synthesized composites were characterized by scanning electron microscopy, X-ray diffraction, vibrating sample magnetometry, Fourier-transform infrared spectroscopy, the Brunauer–Emmett–Teller method, thermogravimetric analysis and X-ray photoelectron spectroscopy, which indicated that the samples comprised of randomly oriented particles with sizes ranging from 20 to 200 nm, and possessed excellent crystallinity, magnetic responsiveness and thermal stability. Additionally, this study explored the application of lanthanum–iron oxide in tenofovir ((R)-9-(2-phosphonomethoxypropyl)adenine, PMPA) adsorption, with a maximum adsorption capacity of 34.06 mg/g under the conditions of adsorbent dosage = 0.9 g/L, pH 4, C = 50 mg/L and t = 25 °C. The lanthanum–iron oxide was simple to prepare and enabled rapid separation, which was beneficial for practical applications.