Modified tamarind kernel polysaccharide: A novel matrix for control release of aspirin

State-of-the-art progress on tamarind seed polysaccharide (Tamarindus indica) and its diverse potential applications, a review with insight

Tamarind seed polysaccharide (TSP) is a biocompatible, non-ionic polymer with antioxidant properties. Its uses include drug delivery, food industry, and wastewater treatment. TSP has various hydroxy functional groups, one of the most favorable sites for graft copolymerization of different monomers. Hence, various chemical methods for TSP modification were developed to satisfy increasing industrial demand. Of particular interest in scientific community are the methods of graft copolymerization because of their ability to alter the physicochemical properties of TSP, including pH sensitivity and the swelling index, leading to improvements in the adsorption efficiency of hazardous heavy metals and dyes from wastewater effluents. Moreover, in recent years, TSP has been used for controlled drug delivery applications due to its unique advantages of high viscosity, broad pH tolerance, non-carcinogenicity, mucoadhesive properties, biocompatibility, and high drug entrapment capacity. In light of the plethora of literature on the topic, a comprehensive review of TSP-based graft copolymers and unmodified and modified TSP important applications is necessary. Therefore, this review comprehensively highlights several synthetic strategies for TSP-grafted copolymers and discusses unmodified and modified TSP potential applications, including cutting-edge pharmaceutical, environmental applications, etc. In brief, its many advantages make TSP-based polysaccharide a promising material for applications in various industries.

Pollen-derived microcapsules for aspirin microencapsulation: in vitro release and physico-chemical studies

Aspirin, also known as acetylsalicylic acid (ASA), is one of the most crucial therapies needed and/or used in a basic health system. Using biocompatible materials to encapsulate ASA would improve its therapeutic efficacy and reduce its side effects via controlled release in physiological environments. Consequently, we explore in this study the feasibility of encapsulation of ASA into robust Lycopodium clavatum L. sporopollenin (LCS) microcapsules. After extracting sporopollenin from their natural micrometer-sized raw spores, the physico-chemical features of the extracted sporopollenin, pure ASA, and sporopollenin loaded with ASA were characterised using various methods, including optical microscopy, Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis.) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Additionally, we demonstrate the in vitro release profile of ASA in a triggered gastrointestinal environment utilizing kinetics analysis to investigate the mechanism of release. The LCS microcapsules were found to be excellent encapsulants for the crucial ASA drug and achieved controlled in vitro release, that would enable further investigations to rationally design versatile controlled delivery platforms.

Controlled Release of Highly Hydrophilic Drugs from Novel Poly(Magnesium Acrylate) Matrix Tablets

The potential of a new poly(magnesium acrylate) hydrogel (PAMgA) as a pharmaceutical excipient for the elaboration of matrix tablets for the extended release of highly hydrophilic drugs was evaluated. The polymer was synthetized with two different crosslinking degrees that were characterized by FTIR and DSC. Their acute oral toxicity was determined in a mouse model, showing no toxicity at doses up to 10 g/kg. Matrix tablets were prepared using metformin hydrochloride as a model drug and the mechanisms involved in drug release (swelling and/or erosion) were investigated using biorrelevant media. This new hydrogel effectively controlled the release of small and highly hydrophilic molecules as metformin, when formulated in matrix tablets for oral administration. The rate of metformin release from PAMgA matrices was mainly controlled by its diffusion through the gel layer (Fickian diffusion). The swelling capacity and the erosion of the matrix tablets influenced the metformin release rate, that was slower at pH 6.8, where polymer swelling is more intensive, than in gastric medium, where matrix erosion is slightly more rapid. The crosslinking degree of the polymer significantly influenced its swelling capacity in acid pH, where swelling is moderate, but not in intestinal fluid, where swelling is more intense.

Erlotinib-loaded carboxymethyl temarind gum semi-interpenetrating nanocomposites

Erlotinib-loaded carboxymethyl temarind gum-g-poly(N-isopropylacrylamide)-montmorillonite based semi-IPN nanocomposites were synthesized and characterized for their in vitro performances for lung cancer therapy. The placebo matrices exhibited outstanding biodegradability and pH-dependent swelling profiles. The molar mass (M¯ c) between the crosslinks of these composites was declined with temperature. The solid state characterization confirmed the semi-IPN architecture of these scaffolds. The corresponding drug-loaded formulations displayed excellent drug-trapping capacity (DEE, 86-97 %) with acceptable zeta potential (-16 to -13 mV) and diameter (967-646 nm). These formulations conferred sustained drug elution profiles (Q_8h, 77-99 %) with an initial burst release. The drug release profile of the optimized formulation (F-3) was best fitted in the first order kinetic model with Fickian diffusion driven mechanism. The mucin adsorption to F-3 followed Langmuir isotherms. The results of MTT assay, AO/EB staining and confocal analyses revealed that the ERL-loaded formulation suppressed A549 cell proliferation and induced apoptosis more effectively than pristine drug.

Semi-interpenetrating nanosilver doped polysaccharide hydrogel scaffolds for cutaneous wound healing

The extensive advancement with novel wound dressing materials functionalized with desirable properties, often touted as a panacea for cuts and burns afflicting various pathologies. However, it would indeed be a hard task to isolate any such material which perfectly fits the needs of any biomedical issue at hand. Biocompatibility, biodegradability as well as non-toxicity of natural polysaccharide served as a versatile and tunable platform for designing natural polysaccharide based scaffolds as an attractive tool in tissue engineering with a greater degree of acceptability. In this regard, we aimed to fabricate a semi interpenetrating hydrogel via exploiting the nontoxic and immune-stimulatory nature of galacto-xyloglucan (PST001) which was further doped with silver nanoparticles to formulate SNP@PST. The wound healing potential of SNP@PST was then studied both with in vitro and preclinical mice models. The current study gives a formulation for cost effective preparation of polysaccharide hydrogels using acrylamide crosslinking with improved biocompatibility and degradability. Wound healing studies in mice proved the efficiency of gels for the clinical application wherein the incorporation of nanosilver greatly enhanced the antimicrobial activity.

Chronotherapeutic drug delivery of Tamarind gum, Chitosan and Okra gum controlled release colon targeted directly compressed Propranolol HCl matrix tablets and in-vitro evaluation

The main objective of this investigation is to develop a chronotherapeutic drug delivery of various natural polymers based colon targeted drug delivery systems to treat early morning sign in BP. The polymers such as Tamarind gum, Okra gum and Chitosan were used in the formulation design. A model drug Propranolol HCl was incorporated in the formulation in order to assess the controlled release and time dependent release potential of various natural polymers. A novel polymer Tamarind gum was extracted and used as a prime polymer in this study to prove the superiority of this polymer over other leading natural polymer. Propranolol HCl was used as a model drug which undergoes hepatic metabolism and witnesses the poor bioavailability. The matrix tablets of Propranolol HCl were prepared by direct compression. The tablets were evaluated for various quality control parameters and found to be within the limits. Carbopol 940 was used as an auxiliary polymer to modify the drug release and physicochemical characteristics of the tablets. The in vitro release studies were performed in 0.1N HCl for 1.5h, followed by pH 6.8 phosphate buffer for 2h and pH 7.4 phosphate buffer till maximum amount of drug release. The in vitro release profile of the formulations were fitted with various pharmacokinetic mathematical models and analyzed for release profile. The formulations prepared with Tamarind gum prolonged the release for an extended period of time compared to other polymer based formulation and showed an excellent compression characteristic.

Polyacrylamide grafted guar gum based glimepiride loaded pH sensitive pellets for colon specific drug delivery: fabrication and characterization

The purpose of this study was to prepare pH-sensitive pellets using an extrusion-spheronization pelletization (ESP) technique.