Application of biodegradable superabsorbent hydrogel composite based on Gum ghatti-co-poly(acrylic acid-aniline) for controlled drug delivery

Capparis sepiaria-Loaded Sodium Alginate Single- and Double-Layer Membrane Composites for Wound Healing

Background: Effective wound dressing is the key solution to combating the increased death rate and prolonged hospital stay common to patients with wounds. Methods: Sodium alginate-based single- and double-layer membranes incorporated with Capparis sepiaria root extract were designed using the solvent-casting method from a combination of polyvinyl alcohol (PVA), Pluronic F127 (PF127), and gum acacia. Results: The successful preparation of the membranes and loading of the extract were confirmed using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The prepared membranes were biodegradable and non-toxic to human skin cells (HaCaT), with high biocompatibility of 92 to 112% cell viability and good hemocompatibility with absorbance ranging from 0.17 to 0.30. The membrane's highest water vapor transmission rate was 1654.7333 ± 0.736 g/m2/day and the highest % porosity was 76%. The membranes supported cellular adhesion and migration, with the highest closure being 68% after 4 days compared with the commercial wound dressings. This membrane exhibited enhanced antimicrobial activity against the pathogens responsible for wound infections. Conclusions: The distinct features of the membranes make them promising wound dressings for treating infected wounds.

Gum Ghatti: A Comprehensive Review on Production, Processing, Remarkable Properties, and Diverse Applications

Gum ghatti, popularly known as Indian gum and obtained from Anogeissus latifolia, is a complex high-molecular-weight, water-soluble, and swellable nonstarch polysaccharide comprised of magnesium and calcium salts of ghattic acids and multiple monosugars. Unlike other nontimber forest produce, gums ghatti is a low-volume but high-value product. It has several applications and is widely used as food, in pharmaceuticals, and for wastewater treatment and hydrogel formation, and it has attracted a great deal of attention in the fields of energy, environmental science, and nanotechnology. Industrial applications of gum ghatti are primarily due to its excellent emulsification, stabilization, thickening, heat tolerance, pH stability, carrier, and biodegradable properties. However, utilization of gum ghatti is poorly explored and implemented due to a lack of knowledge of its production, processing, and properties. Nevertheless, there has been interest among investigators in recent times for exploring its production, processing, molecular skeleton, and functional properties. This present review focuses on production scenarios, processing aspects, structural and functional properties, and potential applications in the food, pharmaceuticals, nonfood, and other indigenous and industrial usages.

Synthesis of GG-g-P(NIPAM-co-AA)/GO and evaluation of adsorption activity for the diclofenac and metformin

The grafting of biopolymer gum ghatti (GG) over the PNIPAM and PAA was done and loaded with graphene oxide (GO). Aim of this work is carried out combine adsorption of sodium diclofenac (SD) and metformin (MF) by the prepared hydrogels under influence of various parameters. The adsorbent GG-g-P(NIPAM-co-PAA)/GO(3 mg) chosen for adsorption activity as it displayed highest swelling capacity. The effect of amount of both adsorbents GG-g-P(NIPAM-co-PAA and GG-g-P(NIPAM-co-PAA)/GO(3 mg) showed that highest adsorption capacity found at 40 mg of adsorbents for both drugs at conditions: 100 mg/L concentration, 30 °C, 24 h and pH 6 and subsequently became stable. Both the drugs were removed in greater amount at 25 mg/L concentration, 24 h of contact time, 30 °C, 40 mg amount of both adsorbents and pH 6. Effect of time revealed that as time elevated from 2 h to 12 (100 mg/L concentration,, 30 °C, 40 mg amount of both adsorbents and pH 6) led to increase adsorption efficiency and after that increase time did not much impact on adsorption activity. Adsorption activity of hydrogels declined with increase of temperature (100 mg/L concentration, 12 h, 40 mg amount of both adsorbents and pH 6). The acidic conditions favored adsorption of SD while MF adsorbed under the weak acidic(100 mg/L concentration, 30 °C, 12 h, 40 mg amount of both adsorbents). However, basic conditions did not much influence on adsorption of MF but effected on adsorption activity of SD. Adsorption isotherm and kinetic model suggested that adsorption is homogenous and chemical in nature. The maximum adsorption capacity (qm) found to be 289.01 and 154.55 mg/g for SD and MF respectively.

Graphical abstract

Supplementary information

The online version contains supplementary material available at 10.1007/s40201-023-00867-w.

Hydrogels: An overview of its classifications, properties, and applications

The review paper starts with the introduction to hydrogels along with broad literature survey covering different modes of synthesis including high energy radiation methods. After that, paper covered broad classification of the hydrogels depending upon the basis of their source of origin, method of synthesis, type of cross-linking present and ionic charges on bound groups. Another advanced category response triggered hydrogels, which includes pH, temperature, electro, and light and substrate responsive hydrogels was also studied. Presented paper summarises chemical structure, properties, and synthesis of different kinds of hydrogels. Main focus was given to the preparation super absorbents such as: Semi-interpenetrating networks (semi-IPNs), Interpenetrating networks (IPNs) and cross-linked binary graft copolymers (BGCPs). The weak mechanical properties and easy degradation limit the uses of bio-based -hydrogels in biomedical field. Their properties can be improved through different chemical and physical methods. These methods were also discussed in the current research paper. Also, it includes development of hydrogels as controlled drug delivery devices, as implants and biomaterials to replace malfunctioned body parts along with their use in several other applications listed in the literature. Literature survey on the application of hydrogels in different fields like biomedical, nano-biotechnology, tissue engineering, drug delivery and agriculture was also carried out.

Biodegradable Gg-cl-poly(NIPAm-co-AA)/-o-MWCNT based hydrogel for combined drug delivery system of metformin and sodium diclofenac: in vitro studies

In the present study Gg-cl-poly(NIPA-co-AA) and Gg-cl-poly(NIPA-co-AA)/-o-MWCNT hydrogels were synthesized using free radical polymerization. We looked into whether combining metformin with diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), would be effective in examining complex formation and analysing the types and intensities of complexes that could result from metformin-diclofenac interactions. The interaction of metformin and diclofenac was studied in vitro at various pH levels and body temperatures. The structure and morphology of the produced hydrogel were characterised using FTIR spectra, SEM analysis, and drug loading tests. As a model drug, the hydrogel was loaded with metformin hydrochloride and sodium diclofenac (DS), and the medicines were released pH-dependently. To explore the drug release kinetics and mechanism, the zero order and first order kinetic models, the Korsemeyar-Peppas model, the Higuchi model, and the Hixson-Crowell model have all been employed. Drug release studies revealed notable characteristics in connection to physiologically predicted pH values, with a high release rate at pH = 9.2. At pH = 9.2, however, both metformin and sodium diclofenac exhibited a Fickian mechanism. Combination treatment may reduce the effective dose of a single drug and hinder metabolic rescue mechanisms. More study is needed to detect any negative effects on individuals.

4D Printing of Hydrogels: Innovation in Material Design and Emerging Smart Systems for Drug Delivery

Advancements in the material design of smart hydrogels have transformed the way therapeutic agents are encapsulated and released in biological environments. On the other hand, the expeditious development of 3D printing technologies has revolutionized the fabrication of hydrogel systems for biomedical applications. By combining these two aspects, 4D printing (i.e., 3D printing of smart hydrogels) has emerged as a new promising platform for the development of novel controlled drug delivery systems that can adapt and mimic natural physio-mechanical changes over time. This allows printed objects to transform from static to dynamic in response to various physiological and chemical interactions, meeting the needs of the healthcare industry. In this review, we provide an overview of innovation in material design for smart hydrogel systems, current technical approaches toward 4D printing, and emerging 4D printed novel structures for drug delivery applications. Finally, we discuss the existing challenges in 4D printing hydrogels for drug delivery and their prospects.

A short review on the synthesis and advance applications of polyaniline hydrogels

Conductive polymeric hydrogels (CPHs) exhibit remarkable properties such as high toughness, self-recoverability, electrical conductivity, transparency, freezing resistance, stimulus responsiveness, stretch ability, self-healing, and strain sensitivity. Due to their exceptional physicochemical and physio-mechanical properties, among the widely studied CPHs, polyaniline (PANI) has been the subject of immense interest due to its stability, tunable electrical conductivity, low cost, and good biocompatibility. The current state of research on PANI hydrogel is discussed in this short review, along with the properties, preparation methods, and common characterization techniques as well as their applications in a variety of fields such as sensor and actuator manufacturing, biomedicine, and soft electronics. Furthermore, the future development and applications of PANI hydrogels are also mentioned.

Synthesis of pH-Sensitive Cross-Linked Basil Seed Gum/Acrylic Acid Hydrogels by Free Radical Copolymerization Technique for Sustained Delivery of Captopril

The pH-sensitive polymeric matrix of basil seed gum (BSG), with two different monomers, such as acrylic acid (AA) and N, N-Methylene-bis-acrylamide (MBA), was selected to use in hydrogels preparation through a free radical copolymerization technique using potassium per sulfate (KPS) as a cross linker. BSG, AA and MBA were used in multiple ratios to investigate the polymer, monomer and initiator effects on swelling properties and release pattern of captopril. Characterization of formulated hydrogels was done by FTIR, DSC/TGA, XRD and SEM techniques to confirm the stability. The hydrogels were subjected to a variety of tests, including dynamic swelling investigations, drug loading, in vitro drug release, sol–gel analyses and rheological studies. FTIR analysis confirmed that after the polymeric reaction of BSG with the AA monomer, AA chains grafted onto the backbone of BSG. The SEM micrographs illustrated an irregular, rough, and porous form of surface. Gel content was increased by increasing the contents of polymeric gum (BSG) with monomers (AA and MBA). Acidic and basic pH effects highlighted the difference between the swelling properties with BSG and AA on increasing concentration. Kinetic modelling suggested that Korsmeyer Peppas model release pattern was followed by the drug with the non-Fickian diffusion mechanism.

Conducting polymer hydrogels as a sustainable platform for advanced energy, biomedical and environmental applications

Environmentally friendly polymeric materials and derivative technologies play increasingly important roles in the sustainable development of our modern society. Conducting polymer hydrogels (CPHs) synergizing the advantageous characteristics of conventional hydrogels and conducting polymers are promising to satisfy the requirements of environmental sustainability. Beyond their use in energy and biomedical applications that require exceptional mechanical and electrical properties, CPHs are emerging as promising contaminant adsorbents owing to their porous network structure and regulable functional groups. Here, we review the currently available strategies for synthesizing CPHs, focusing primarily on multifunctional applications in energy storage/conversion, biomedical engineering and environmental remediation, and discuss future perspectives and challenges for CPHs in terms of their synthesis and applications. It is envisioned to stimulate new thinking and innovation in the development of next-generation sustainable materials.

Formulation, In Vitro Evaluation, and Toxicity Studies of A. vulgaris-co-AAm Carrier for Vildagliptin

This study investigated the use of Artemisia vulgaris L. seed mucilage as a new excipient for sustained delivery of Vildagliptin. Copolymeric carrier of A. vulgaris seed mucilage-co-AAm was devised by using acrylamide (AAm) as a monomer, methylene-bis-acrylamide (MBA) as a crosslinker, and potassium persulfate (KPS) as an initiator through free radical polymerization. Different formulations of A. vulgaris-co-AAm were devised by varying contents of polymer, monomer, crosslinking agent, initiator, and reaction temperature. Copolymeric structures were characterized through XRD analysis, Fourier transform infrared (FTIR) spectroscopy, TGA and DSC analysis, and scanning electron microscopy. Porosity, gel fraction, and Vildagliptin loading capacity of copolymers were also established. Swelling and in vitro drug release studies were conducted. XRD evaluation showed the alteration of the crystalline structure of Vildagliptin into an amorphous form. FTIR analysis confirmed the successful grafting of AAm to A. vulgaris seed mucilage backbone. Porosity was increased with increasing polymer concentration and reaction temperature while it was decreased with an increasing amount of AAm, MBA, and KPS. Gel content was decreased with increasing polymer concentration and reaction temperature while it was increased with an increasing amount of AAm, MBA, and KPS. Acute oral toxicity of copolymeric network was done in animal models to evaluate the safety. Copolymers showed the same swelling behavior at all pH 1.2, 4.5, 6.8, and 7.4. Vildagliptin release from copolymer showed a cumulative trend by increasing polymer content and reaction temperature, while a declining trend was observed with increasing contents of monomer, crosslinking agent, and initiator. Sustained release of Vildagliptin was observed from copolymers and release followed the Korsmeyer-Peppas model. From the acute oral toxicity studies, it is evident that newly synthesized copolymeric carriers are potentially safe for eyes, skin, and vital organs.

Superabsorbent Hydrogels Based to Polyacrylamide/Cashew Tree Gum for the Controlled Release of Water and Plant Nutrients

Agricultural production is influenced by the water content in the soil and availability of fertilizers. Thus, superabsorbent hydrogels, based on polyacrylamide, natural cashew tree gum (CG) and potassium hydrogen phosphate (PHP), as fertilizer and water releaser were developed. The structure, morphology, thermal stability and chemical composition of samples of polyacrylamide and cashew tree gum hydrogels with the presence of fertilizer (HCGP) and without fertilizer (HCG) were investigated, using X-ray diffractometry (XRD), Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Thermogravimetric Analysis (TGA/DTG) and Energy Dispersive Spectroscopy (EDS). Swelling/reswelling tests, textural analysis, effect of pH, release of nutrients and kinetics were determined; the ecotoxicity of the hydrogels was investigated by the Artemia salina test. The results showed that PHP incorporation in the hydrogel favored the crosslinking of chains. This increased the thermal stability in HCGP but decreased the hardness and adhesion properties. The HCGP demonstrated good swelling capacity (~15,000 times) and an excellent potential for reuse after fifty-five consecutive cycles. The swelling was favored in an alkaline pH due to the ionization of hydrophilic groups. The sustained release of phosphorus in HCGP was described by the Korsmeyer-Peppas model, and Fickian diffusion is the main fertilizer release mechanism. Finally, the hydrogels do not demonstrate toxicity, and HCGP has potential for application in agriculture.

Stimuli-responsive natural gums-based drug delivery systems for cancer treatment

Chemotherapy as the main cancer treatment method has non-specific effects and various side-effects. Accordingly, significant attempts have been conducted to enhance its efficacy through design and development of "smart" drug delivery systems (DDSs). In this context, natural gums, as a nice gift by the nature, can be exploited as stimuli-responsive DDSs for cancer treatment in part due to their renewability, availability, low cost, bioactivity, biocompatibility, low immunogenicity, biodegradability, and acceptable stability in both in vitro and in vivo conditions. However, some shortcomings (e.g., poor mechanical properties and high hydration rate) restrict their biomedical application ranges that can be circumvented through modification process (e.g., grafting of stimuli-responsive polymers or small molecules) to obtain tailored biomaterials. This review article aimed to compile the stimuli-responsive DDSs based on natural gums. In addition, different types of stimuli, the fundamental features of natural gums, as well as their chemical modification approaches are also shortly highlighted.

Mass spectrometry in bioresorbable polymer development, degradation and drug-release tracking

A detailed characterization of polymeric matrices and appropriate degradation monitoring techniques are required to sustain the development of new materials as well as to enlarge the applications of the old ones. In fact, polymer analysis is essential for the clarification of the intrinsic relationship between structure and properties that ascertains the industrial applications in diverse fields. In bioresorbable and biodegradable polymers, the role of analytical methods is dual since it is pointed both at the polymeric matrices and at degradation tracking. The structural architectures, the mechanical and morphological properties, and the degradation rate, are of outstanding importance for a specific application. In some cases, the complexity of the polymer structure, the processes of decomposition or the low concentration of the degradation products need the concurrent use of different complementary analytical techniques to give detailed information of the reactions taking place. Several analytical methods are used in bioresorbable polymer development and degradation tracking. Among them, mass spectrometry (MS) plays an essential role and it is used to refine polymer syntheses, for its high sensitivity, to highlight degradation mechanism by detecting compounds present in trace amounts, or to track the degradation product profile and to study drug release. In fact, elucidation of reaction mechanisms and polymer structure, attesting to the purity and detecting defects as well as residual catalysts, in biodegradable and bioresorbable polymers, requires sensitive analytical characterization methods that are essential in providing an assurance of safety, efficacy and quality. This review aims to provide an overview of the MS strategies used to support research and development of resorbable polymers as well as to investigate their degradation mechanisms. It is focused on the most significant studies concerning synthetic bioresorbable matrices (polylactide, polyglycolide and their copolymers, polyhydroxybutyrate, etc.), published in the last ten years.

Multi-Functional Laccase Immobilized Hydrogel Microparticles for Efficient Removal of Bisphenol A

Hghly stable, reusable, and multi-functional biocatalytic microparticles with Laccase (Lac) enzyme (Lac/particles) were synthesized for bisphenol A (BPA) removal from aqueous solution. The Lac/particles were prepared by encapsulating Lac enzymes into poly ethylene glycol (PEG) hydrogel via the UV assisted emulsion polymerization method followed by cross linking with glutaraldehyde (GA). The obtained Lac/particles were spherical and micron sized (137⁻535 μm), presenting high enzyme entrapment efficiency of 100%, high activity recovery of 18.9%, and great stability at various pHs (3⁻7) than the free Lac. The Lac/particles could adsorb the BPA into the catalytic particles in a short time, promoting contact between BPA and enzyme, and further enzymatically degrade them without the shaking process and independent surrounding buffer solution. The Lac/particles could be reused for another round BPA adsorption and biotranformation by maintaining over 90% of BPA removal efficiency after seven times reuse. The synergistic effects of adsorption and biocatalytical reaction of Lac/particles have significant values in high efficient and cost-effective BPA removal.

Preparation and characterization of pH sensitive crosslinked Linseed polysaccharides-co-acrylic acid/methacrylic acid hydrogels for controlled delivery of ketoprofen

Some pH responsive polymeric matrix of Linseed (Linum usitatissimum), L. hydrogel (LSH) was prepared by free radical polymerization using potassium persulfate (KPS) as an initiator, N,N-methylene bisacrylamide (MBA) as a crosslinker, acrylic acid (AA) and methacrylic acid (MAA) as monomers; while ketoprofen was used as a model drug. Different formulations of LSH-co-AA and LSH-co-MAA were formulated by varying the concentration of crosslinker and monomers. Structures obtained were thoroughly characterized using Fourier transforms infrared (FTIR) spectroscopy, XRD analysis and Scanning electron microscopy. Sol-gel fractions, porosity of the materials and ketoprofen loading capacity were also measured. Swelling and in vitro drug release studies were conducted at simulated gastric fluids, i.e., pH 1.2 and 7.4. FTIR evaluation confirmed successful grafting of AA and MAA to LSH backbone. XRD studies showed retention of crystalline structure of ketoprofen in LSH-co-AA and its amorphous dispersion in LSH-co-MAA. Gel content was increased by increasing MBA and monomer content; whereas porosity of hydrogel was increased by increasing monomer concentration and decreased by increasing MBA content. Swelling of copolymer hydrogels was high at pH 7.4 and low at pH 1.2. Ketoprofen release showed an increasing trend by increasing monomer content; however it was decreased with increasing MBA content. Sustained release of ketoprofen was noted from copolymers and release followed Korsmeyer-Peppas model.

Synthesis and biomedical applications of fluorescent nanogels

Fluorescent nanogel is an innovative biomedical material with hydroscopicity, degradability, and responsiveness.