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This study presents a sustainable method for producing iron oxide nanoparticles (FeO NPs) using aqueous extracts from coffee seeds. Characterization through X-ray diffraction (XRD), scanning electron microscopy, and transmission electron microscopy (TEM) revealed non-spherical NPs ranging from 30 to 50 nm. The XRD analysis confirmed that the face-centred cubic structure and the Debye–Scherrer’s crystalline size support the FeO particle size confirmed from TEM. The synthesized NPs demonstrated significant antimicrobial activity against Escherichia coli and Staphylococcus aureus, as well as antifungal activity against Aspergillus niger. Additionally, they exhibited potent antioxidant properties, effectively inhibiting DPPH, α-amylase, and α-glucosidase compared to acarbose and coffee extract. The findings suggest that these FeO NPs hold promise as antimicrobial, antioxidant, antifungal, and potentially antidiabetic agents.

Synthesis of cadmium sulfide (CdS) nanoparticles using watermelon rind aqueous extract was explored for its effectiveness in eliminating Methylene Blue (MB) and Crystal Violet (CV) dyes from water. The synthesised CdS nanoparticles were characterised with XRD, TEM and EDX and found to be around 10 nm in size with spherical shape. A central composite design was developed to optimise independent variables such as pH, contact time and initial concentrations. The developed quadratic model was found to be significant with p-value <0.0001 and lack of fit >0.005 suggesting the reliability of the model. Isotherm modelling analysis revealed that Langmuir and Freundlich's isotherms provided better explanation for the equilibrium data. The loading capacities of the CdS nanoparticles were found be 227.3 and 185.1 mg g-1, respectively for MB and CV. The experimental data showed a good fit with the pseudo-second-order kinetic model, indicating that chemical reactions were the determining factor in controlling the rate-limiting step. Thermodynamic analyses indicated that the process was spontaneous and exothermic. Desorption and regeneration investigations demonstrated that CdS nanoparticles could be successfully regenerated up to 5 times and reused in the adsorption process. The results conclude that the CdS nanoparticles are capable of remediating water containing cationic dyes. [ABSTRACT FROM AUTHOR]

Watermelon rind (WR) an agro-waste was protonated aiming to eliminate the alkali and alkaline metal ions and investigated towards adsorption of Cd2+ ions in a continuous process. The protonation step resulted in the elimination of K+ and Mg2+ ions from the watermelon rind surface, and the protonation was confirmed with FTIR and EDX techniques. Comparative investigations were carried out between native and protonated WR in a continuous process, and parameters such as rate of flow, feed concentration and bed heights were optimised. At higher bed depths and lower rates of flow and initial feed concentrations, the columns provided maximum adsorption of Cd2+ ions. Optimal conditions in this study were found to be 1 ml, 3 cm and 50 mg L−1, respectively, for flow rate, bed depths and initial concentrations. The adsorption capacity of native and protonated WR was experimentally calculated to be 97.9 and 107.3 mg g−1, respectively. The PWR exhibited higher adsorption capacity compared to WR, and this is due to the protonation step, which eliminated the alkali and alkaline metal ions bound onto the WR surface that blocked the active sites. The data obtained in the continuous columns were fitted to mathematical models such as Adams–Bohart, Thomas and Yoon–Nelson models, and the later models were able to explain the adsorption process well. Lastly, regeneration of the WR and PWR was investigated, and 0.1 M HCl exhibited higher desorption and regeneration efficiency compared to 0.1 M acetic acid. These results suggest that the protonation of watermelon rind results in enhanced adsorption of Cd ions, and both native and protonated are effective adsorbents. [ABSTRACT FROM AUTHOR]

Gojjala Venugopalarao,1 Rajasekhar Lakshmipathy,2 Nallani Chakravarthula Sarada1 1Environmental and Analytical Chemistry Division, School of Advanced Sciences, VIT University, Vellore, 2Centre for Material Science, KCG College of Technology, Chennai, India Background: The application of antibiotics has been limited due to weak biodistribution and pharmacokinetics. Encapsulation of these drugs in lipid vesicles might be a good solution for obtaining the required properties. Liposomes are one of the most suitable drug-delivery systems to deliver the drug to the target organ and minimize the distribution of the drug to non-target tissues.Objective: The study reported here aimed to develop cefditoren pivoxil liposomes by thin-film hydration, characterize them in terms of physical interactions, and undertake in vitro and in vivo release studies.Methodology: The pre-formulation studies were carried out using Fourier-transform infrared spectroscopy and differential scanning calorimetry. Cefditoren pivoxil liposomal formulations were formulated by thin-film hydration using biomaterials ie, soya lecithin and cholesterol in different molar ratios. The best molar ratio was determined by in vitro studies such as entrapment efficacy, particle size distribution, and diffusion.Results: From the in vitro release studies, it was found that the formulation that contained soya lecithin and cholesterol in a 1.0:0.6 molar ratio gave good entrapment of 72.33% and drug release of 92.5% at 36 hours. Further, the formulation’s zeta potential and surface morphology were examined and stability and in vivo studies were undertaken evaluating the pharmacokinetic parameters, which showed promising results.Conclusion: Formulation CPL VI showed the maximum drug-loading capacity of 72.3% with good controlled release and acceptable stability when compared with the other formulations. In vivo studies in rabbits showed that the drug release from the liposomes was successfully retarded with good controlled release behavior which can be used to treat many bacterial infections with a minimal dose. Keywords: biomaterials, liposomes, drug-delivery system, soya lecithin, cholesterol

Rajasekhar Lakshmipathy,1 Nallani Chakravarthula Sarada,2 K Chidambaram,3 Sk Khadeer Pasha3 1Centre for Material Science, KCG College of Technology, Chennai, Tamil Nadu, India; 2Environmental and Analytical Chemistry Division, 3Material Physics Division, School of Advanced Sciences, VIT University, Vellore, Tamil Nadu, India Abstract: We investigated the one-step synthesis of CdS nanoparticles via green synthesis that used aqueous extract of watermelon rind as a capping and stabilizing agent. Preliminary phytochemical analysis depicted the presence of carbohydrates which can act as capping and stabilizing agents. Synthesized CdS nanoparticles were characterized using UV-visible, Fourier transform infrared spectroscopy, X-ray diffraction, EDX, dynamic light scattering, transmission electron microscopy, and atomic force microscopy techniques. The CdS nanoparticles were found to be size- and shape-controlled and were stable even after 3 months of synthesis. The results suggest that watermelon rind, an agro-waste, can be used for synthesis of CdS nanoparticles without any addition of stabilizing and capping agents. Keywords: green synthesis, nanoparticles, biomimetic, atomic force microscopy

This study reports the use of hydrophobic ionic liquid (IL) based on D-galactose for the recovery of Ce (III) and Pr (III) ions from solutions. The equilibrium data were obtained by optimization of batch parameters, and various isotherms and kinetic models were utilised to predict the mechanistic process of sequestration of ions. The Arrhenius activation energies are found to be between 5-40 kJ, suggesting the physisorption process of ions onto IL. The present process is understood to be rapid and exothermic in nature according to thermodynamic experiments. The loading capacity was found to be 179.3 g L-1 and 141.5 g L-1, respectively, for Ce (III) and Pr (III) ions at pH 5 with a contact time of 30 min and dose being 0.1 g L-1. The higher uptake capacity is attributed to the presence of a highly electronegative fluorine atom in the IL. These results highlight the potential application of IL in the sequestration of Ce (III) and Pr (III) ions from any water sources. [ABSTRACT FROM AUTHOR]