Maleated Chitosan as Competent Biopolymer-Based Corrosion Inhibitor for Copper in 3.5 wt/vol% NaCl Medium Himanshi Tyagi, Vignesh Vasudevan, Dipankar Das, Amrita Biswas Polymers for Advanced Technologies, 2026 Design and development of eco‐friendly corrosion inhibitors have high demand due to environmental concern, where the employment of biopolymers plays an important role. In this study, an eco‐friendly corrosion inhibitor (maleated chitosan) was developed by modifying chitosan with maleic anhydride by an amidation reaction and used for copper in artificial sea water medium (3.5 wt/vol% NaCl). The maleated chitosan was characterized by FTIR, FESEM, EDX, zeta potential measurement, and solubility study. Contact angle measurement data indicated that the hydrophobicity of the copper surface increased with the addition of the inhibitor. To evaluate their inhibition performance, potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) methods were employed. Both PDP and EIS studies showed that 300 ppm maleated chitosan increased almost 9%–10% of corrosion inhibition efficiency compared to pristine chitosan. Experimental results showed that the inhibitors (chitosan and maleated chitosan) were mixed‐type in nature, and the adsorption process followed the Langmuir isotherm. Finally, it is anticipated that simple preparation procedure and improved anti‐corrosive activity of maleated chitosan may create a noteworthy influence for mitigating copper corrosion in desalination and maritime sectors.
Preparation of Photoclick-Crosslinked Modular Gelrite Hydrogel: Tuning Physico-Chemical Characteristics, Cytocompatibility, In Vitro Cefixime Trihydrate Release, and Antimicrobial Properties Ejjurothu Ramya Lakshmi Keerthana, Shivangi Parhi, Abdullahi Dahiru Datti, Muthuraj Marimuthu, Paulomi Ghosh, Tarak Nath Mandal, Dipankar Das Macromolecular Bioscience, 2026 The fabrication of a modular Gelrite‐based covalently crosslinked hydrogelator (Gelrite‐MA) by photo‐initiated click chemistry to facilitate cefixime trihydrate administration is reported for the first time. Modular Gelrite is prepared via base (DIPEA)‐catalyzed esterification reaction between Gelrite and maleic anhydride. Under the UV light, the modular Gelrite containing carbon‐carbon double bonds undergoes a photocrosslinking reaction with 2, 2ʹ‐(Ethylenedioxy)diethanethiol and forms the hydrogelator. Comprehensive characterization of the modular Gelrite‐based compound is done using various methods. The significant differences in the hydrogelator's swelling ratio at pH values of 1.2 and 6.8 demonstrate its pH‐responsive behavior. The rheological analysis shows that the yield stress value of Gelrite‐MA hydrogel is higher at pH 1.2 (2542 Pa) than at pH 6.8 (258 Pa). The Gelrite‐MA hydrogel is cytocompatible, showing 128.8 ± 5.9% cell viability against L929 cell lines after 3 days. The Gelrite‐MA hydrogel formulation demonstrates sustained release matrix characteristics, releasing 79.4±3.1% of total cefixime over 30 h. The 5 mg hydrogel‐cefixime formulation effectively suppresses the inhibition of Escherichia coli and Staphylococcus aureus , with ZOI of 55.3 ± 1.5 mm and 42.0 ± 2.0 mm, respectively. The lower minimum inhibitory concentration value suggests that the hydrogel formulation is more potent against E. coli (MIC = 39 µg/mL) bacteria than S. aureus (MIC = 5 mg/mL). Therefore, the prepared cytocompatible and pH‐responsive Gelrite‐MA hydrogel has the potential to serve as a sustained drug delivery matrix for administering cefixime trihydrate orally.
Biocompatible PVA-GG-MgO Nanocomposite Films: Enhanced Antibacterial and Antioxidant Properties for Potential Food Packaging Applications M. Archana, Shivangi Parhi, Paulomi Ghosh, Rahul Narayanan, Abhilash Pullanchiyodan, Dipankar Das Polymer Engineering and Science, 2025 This work describes the fabrication of a hybrid film based on polyvinyl alcohol (PVA), guar gum (GG), and nanostructured magnesium oxide (MgO) for its uses in the packaging sector. The nanostructured MgO was synthesized by the precipitation method using Boerhavia diffusa (BD) leaf extract as a stabilizing and reducing agent. The presence of phytochemicals in the leaf extract was confirmed by mass spectrometric analysis. A variety of characterization methods were used to identify the MgO‐based nanomaterial. The MgO‐based nanomaterial's SEM examination revealed a structure that resembled a flower. The various functional groups in the hybrid films and PVA, GG, and MgO‐based nanomaterials were confirmed by Fourier transform infrared (FTIR) spectroscopy. The PVA matrix's mechanical qualities, moisture absorption, aqueous stability, and thermal stability were enhanced by the addition of GG and MgO‐based nanomaterials. The hybrid film demonstrated 100% bactericidal effectiveness and 17.3% ± 3.9% antioxidant activity, according to the results of the antibacterial and DPPH assays, respectively. The food preservation test demonstrated that the PVA‐GG‐MgO4% film can preserve the cherries (Prunus avium) better up to day 7 compared to the PVA film, while its performance was comparable to that of aluminum foil. These results clearly indicate that the developed hybrid film could be suited for packaging applications.
Advances in synthetic strategies and applications of polymeric hydrogels Bharat Gajurel, Kham Bahadur Tamang, Dipankar Das, Rameshwar Adhikari Polymer Engineering and Science, 2025 Hydrogels are three‐dimensional networks of hydrophilic polymers capable of absorbing and retaining a significant amount of water while maintaining their structural integrity. Their biocompatibility, tunable physical characteristics, and resemblance to the extracellular matrix make them highly versatile in biomedical engineering. This paper provides a comprehensive overview of hydrogels, covering their historical development, classification, and synthetic and fabrication strategies tailored for specific applications. Their widespread use spans biomedical, industrial, and environmental fields, driven by their high water retention, biocompatibility, and responsiveness to external stimuli. In biomedicine, hydrogels play a crucial role in drug delivery, wound healing, tissue engineering, biosensing, and bioprinting, with applications extending to cardiac regeneration and neural tissue growth. Additionally, they function as smart materials in sensors and actuators and contribute to advancements in flexible electronics and energy storage. Finally, current trends, challenges, and opportunities of the hydrogel have been summarized.Highlights New synthetic strategies for hydrogel (HG) have been elucidated. Enhanced biocompatibility boosts HG applications in life sciences. HG haspotential uses in biomedical field, controlled drug delivery and release. Advanced HGs have tunable characteristics needed for various applications.
Antimicrobial, Anticancer, and Antioxidant Activities of Zinc Oxide Nanoparticles Synthesized Using Ethyl Acetate Extract of Ageratum houstonianum Mill. Leaf Enna Choudhary, Sahil Kumar, Navneet Bithel, Amrita Biswas, Dipankar Das, Chiranjib Banerjee Chemistryselect, 2024 In the era of increasing antimicrobial resistance towards conventional antibiotics, antimicrobial nanoparticles appeared as one of the best alternatives. In the present study, zinc oxide nanoparticles (ZnO NPs) were prepared using ethyl acetate extract of Ageratum houstonianum Mill. leaf. The ZnO NPs were analyzed using different characterization techniques. A characteristic stretching frequency at 498 cm−1 in the FTIR spectrum and the XRD result indicated the formation of ZnO. FESEM and HRTEM images revealed that ZnO NPs were spherical‐shaped. The zeta potential data implied that the produced ZnO NPs were anionic (−15.5 mV). Furthermore, the antimicrobial activity of ZnO NPs was performed against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumoniae and showed the highest efficiency toward S. aureus with a zone of inhibition of 14.3 ± 0.3 mm. Synthesized ZnO NPs exhibited antioxidant activity with an IC50 of 110.59 µg/mL. The in vitro cell study with synthesized ZnO NPs ascertained that the NPs exhibited anticancer activity against breast cancer cell lines (MCF‐7) with the IC50 value of around 65 µg/mL. Overall, these findings showed that ZnO NPs synthesized using A. houstonianum Mill. leaf extract have antibacterial, antioxidant, and anticancer activities and could be used for therapeutic applications.
Design, Characterization, and Biocompatibility of Modular Biopolymer-Based Single- and Double-Cross-Linked Networks Hydrogels Dipankar Das, Aysha Awan, Kawaljit Kaur, Mareike Müller, Holger Schönherr ACS Applied Polymer Materials, 2024 The synthesis of the modular ketone-rich dextrin acetoacetate (DXTAA) and its application in the click chemistry-based synthesis of single-cross-linked network (SN) and double-cross-linked network (DN) biopolymeric hydrogels are reported. DXTAA is obtained in a base-catalyzed transesterification reaction between dextrin and tert -butyl acetoacetate. DXTAA forms covalently cross-linked SN hydrogels with a hydrazide derivative of alginate (Alg-SDH) via hydrazone linkages in aqueous solution without any initiator, heat, or catalyst. The presence of carboxylate groups in Alg-SDH enables the preparation of DN hydrogels using calcium ions as an ionic cross-linker. The swelling ratio and the stability of the hydrogels are shown to be pH-dependent; the DN hydrogel exhibits considerably higher stability at pH 7.4 compared to the SN hydrogel. Both hydrogels are shown to be noncytotoxic and biocompatible. Thus, DXTAA can be considered a promising cross-linker for the in situ click synthesis of biocompatible gel.
Cytocompatible hydrogel derived from dextrin and Poly(N-Vinyl acetamide) toward controlled antimicrobial release Dipankar Das, Shaon Dey, Sagar Pal Journal of Macromolecular Science Part A Pure and Applied Chemistry, 2024 The work aims to develop a biopolymer-dextrin-based three-dimensional crosslinked hydrophilic material for antimicrobial delivery. The copolymer (Dxt-PNVA) has been prepared by in-situ grafting of poly(N-vinylacetamide), followed by cross-linking with N,N'-methylenebisacrylamide with dextrin. By varying the concentrations of the reactants, an optimized copolymer (Dxt-PNVA 5) with the lowest % of crosslinking has been chosen for biomedical applications. The copolymeric gel has been characterized in detail using various techniques, followed by its cytocompatibility study using HeLa Cell lines that confirm the cytocompatible nature of the material. Copolymeric gel is a suitable material for the effective release of two antimicrobials (amoxicillin trihydrate and ornidazole) from tablet formulation for a prolonged period of 24 h. The obtained data demonstrates that the cytocompatible hydrogel has the potential characteristics of a daily dose administration for amoxicillin trihydrate and ornidazole.
