Biodegradable IPN hydrogel beads of pectin and grafted alginate for controlled delivery of diclofenac sodium

Characterization of Taro (Colocasia esculenta) stolon polysaccharide and evaluation of its potential as a tablet binder in the formulation of matrix tablet

This investigation focuses on the extraction, characterization, and evaluation of taro (Colocasia esculenta) stolon polysaccharide (TSP) as a tablet binding agent, which is obtained from edible taro stolon. TSP was subjected to phytochemical screening and characterized by FTIR, DSC, TGA, DTA, XRD, particle size, polydispersity index, zeta potential, rheological behavior, and SEM. The tablets prepared with varying concentrations of TSP (2.5 %, 5 %, 7.5 %, and 10 % w/w) and diclofenac sodium (DS) were evaluated and compared with the same concentrations of gum acacia and PVP K-30. The presence of carbohydrates was confirmed by Molisch's test. The FTIR spectra established the compatibility of the drug with excipients. The SEM images revealed asymmetric and elongated particles of TSP powder. The hydration kinetics study showed matrix hydration and water penetration velocity within the range of 0.602-0.753 g/g and 0.112-0.189 cm/g.h, respectively. The tablets showed drug release of >75 % at 45 min. The release-exponent value above 0.89 indicated a super case II drug transport combining matrix erosion and diffusion. Optimum tablet hardness and very low friability, even at 2.5 % binder concentration, suggested the potential application of the novel TSP as a tablet binder in the formulation of the tablets.

Rational modification of xanthan gum based on assistance of molecular dynamics simulation

Graft copolymerization is an effective approach to improve performance of polysaccharide. However, selecting the most suitable modification strategy can be challenging due to the intricate molecular structure. Rational design through computer aided molecular dynamics (MD) simulations requires substantial computational resources. This study designed a simplified MD simulation strategy and suggested that grafting acrylamide (AM) could effectively adjust the molecular conformation of xanthan gum (XG) and its derivatives, thus regulating its viscosity and gelation properties. To rationally modify XG, a uniform experimental design was applied to tune the grafting ratios ranging from 72 % to 360 %, resulting in XG-AM solutions with viscosity ranging from 9 to 104 mPa•s at a concentration of 0.3 %. XG-AM was crosslinked by acid phenolic resin to generate gel with the viscosity of 7890 mPa·s in 3 days, which was 13 times the viscosity of unmodified XG. The controllable gelation will enhance the efficacy of XG-AM in oil recovery. By integrating rational selection of grafting strategies based on simplified MD simulation of polysaccharide derivatives and controllable grafting modification with specified grafting rates, customized production of polysaccharide derivatives can meet the requirements of a diverse range of applications.

Research progresses on carboxymethyl xanthan gum: Review of synthesis, physicochemical properties, rheological characterization and applications in drug delivery

Xanthan gum is a nonionic polysaccharide widely explored in biomedical, nutraceutical, and pharmaceutical fields. XG suffers from several drawbacks like poor dissolution, lower bioavailability and an inability to form hydrogels. The carboxymethyl derivative of XG, CMX, has better solubility, dissolution, and bioavailability characteristics. Moreover, due to its anionic character, it forms water insoluble hydrogels upon crosslinking with metal cations. CMX hydrogels are used to prepare matrix tablets, microparticles, beads, and films. CMX hydrogels has been used in drug delivery and tissue engineering fields. CMX hydrogels are used for sustained gastrointestinal, colon targeted, and transdermal delivery of drugs. CMX nanoparticles have been used for targeted delivery of anticancer drugs to tumor cells. CMX hydrogels have already made significant strides in drug delivery and tissue engineering fields. Further understanding of the physicochemical properties and rheological characteristics of CMX would enable researchers to explore newer applications of CMX. This review article thus aims to discuss the synthesis, physicochemical properties, and rheological characteristics of CMX. The article also gives critical insights on the versatility of CMX as a drug delivery carrier and presents prospective trends on applications of CMX.

Effect of intragranular/extragranular tara gum on sustained gastrointestinal drug delivery from semi-IPN hydrogel matrices

The present research was undertaken to develop semi-IPN hydrogel matrix tablets of tara gum (TG) and carboxymethyl TG (CMTG) for sustained gastrointestinal delivery of highly water soluble tramadol hydrochloride (TH). The matrix tablets were developed by a hybrid process of wet granulation and direct compression technique. Carboxymethyl TG was crosslinked with dual cross-linking ions (Al3+/Ca2+). The uncross-linked component of the semi-IPN matrix was either incorporated within the granules (intragranular TG) or incorporated outside the granules (extragranular TG), prior to compression. The effect of intragranular/extragranular TG on the swelling, erosion and TH release characteristics from the semi-IPN hydrogel matrix tablets was investigated. The key finding of the investigation indicated that intragranular TG expedited TH release, while extragranular TG sustained TH release. Moreover, the effect of cross-linking ions on viscosity, rigidity, cross-link density and TH release behavior from hydrogel matrices was investigated. In-vivo pharmacokinetic performance of the optimized extragranular TG semi-IPN hydrogel matrix (F15) indicated sustained TH release in gastrointestinal milieu.

Pectin Hydrogels: Gel-Forming Behaviors, Mechanisms, and Food Applications

Pectin hydrogels have garnered significant attention in the food industry due to their remarkable versatility and promising properties. As a naturally occurring polysaccharide, pectin forms three-dimensional (3D) hydrophilic polymer networks, endowing these hydrogels with softness, flexibility, and biocompatibility. Their exceptional attributes surpass those of other biopolymer gels, exhibiting rapid gelation, higher melting points, and efficient carrier capabilities for flavoring and fat barriers. This review provides an overview of the current state of pectin gelling mechanisms and the classification of hydrogels, as well as their crosslinking types, as investigated through diverse research endeavors worldwide. The preparation of pectin hydrogels is categorized into specific gel types, including hydrogels, cryogels, aerogels, xerogels, and oleogels. Each preparation process is thoroughly discussed, shedding light on how it impacts the properties of pectin gels. Furthermore, the review delves into the various crosslinking methods used to form hydrogels, with a focus on physical, chemical, and interpenetrating polymer network (IPN) approaches. Understanding these crosslinking mechanisms is crucial to harnessing the full potential of pectin hydrogels for food-related applications. The review aims to provide valuable insights into the diverse applications of pectin hydrogels in the food industry, motivating further exploration to cater to consumer demands and advance food technology. By exploiting the unique properties of pectin hydrogels, food formulations can be enhanced with encapsulated bioactive substances, improved stability, and controlled release. Additionally, the exploration of different crosslinking methods expands the horizons of potential applications.

Curcumin-Based Nanoformulations: A Promising Adjuvant towards Cancer Treatment

Throughout the United States, cancer remains the second leading cause of death. Traditional treatments induce significant medical toxic effects and unpleasant adverse reactions, making them inappropriate for long-term use. Consequently, anticancer-drug resistance and relapse are frequent in certain situations. Thus, there is an urgent necessity to find effective antitumor medications that are specific and have few adverse consequences. Curcumin is a polyphenol derivative found in the turmeric plant (Curcuma longa L.), and provides chemopreventive, antitumor, chemo-, and radio-sensitizing properties. In this paper, we summarize the new nano-based formulations of polyphenolic curcumin because of the growing interest in its application against cancers and tumors. According to recent studies, the use of nanoparticles can overcome the hydrophobic nature of curcumin, as well as improving its stability and cellular bioavailability in vitro and in vivo. Several strategies for nanocurcumin production have been developed, each with its own set of advantages and unique features. Because the majority of the curcumin-based nanoformulation evidence is still in the conceptual stage, there are still numerous issues impeding the provision of nanocurcumin as a possible therapeutic option. To support the science, further work is necessary to develop curcumin as a viable anti-cancer adjuvant. In this review, we cover the various curcumin nanoformulations and nanocurcumin implications for therapeutic uses for cancer, as well as the current state of clinical studies and patents. We further address the knowledge gaps and future research orientations required to develop curcumin as a feasible treatment candidate.

Current update on psyllium and alginate incorporate for interpenetrating polymer network (IPN) and their biomedical applications

Natural polysaccharides and their designed structures are extremely valuable due to their intrinsic pharmacological properties and are also used as pharmaceutical aids. These naturally occurring polysaccharides (e.g., psyllium and alginate) are gaining popularity for their use in the preparation of interpenetrating polymer network (IPN) materials with improved swelling ability, biodegradability, stability, non-cytotoxic, biocompatibility, and cost-effectiveness. IPN is prepared sequentially or simultaneously by microwave irradiation, casting evaporation, emulsification cross-linking, miniemulsion/inverse miniemulsion technique, and radiation polymerization methods. In addition, the prepared IPNs have has been extensively characterized using various analytical and imaging techniques before sustainable deployment for multiple applications. Regardless of these multi-characteristic attributes, the current literature lacks a detailed overview of the biomedical aspects of psyllium, alginate, and their engineered IPN structures. Herein, we highlight the unique synthesis, structural, and biomedical considerations of psyllium, alginate, and engineered IPN structures. In this review, a wide range of biomedical applications, such as role as a drug carrier for sustain delivery, wound dressing, tissue engineering, and related miscellaneous application of psyllium, alginate, and their IPN structures described with appropriate examples. Further research will be carried out for the development of IPN using psyllium and alginate, which will be a smart and active carrier for drugs used in the treatment of life-threatening diseases due to their inherent pharmacological potential such as hypoglycemic, immunomodulatory, antineoplastic, and antimicrobial.

Oral peptide delivery: challenges and the way ahead

Peptides and proteins have emerged as potential therapeutic agents and, in the search for the best treatment regimen, the oral route has been extensively evaluated because of its non-invasive and safe nature. The physicochemical properties of peptides and proteins along with the hurdles in the gastrointestinal tract (GIT), such as degrading enzymes and permeation barriers, are challenges to their delivery. To address these challenges, several conventional and novel approaches, such as nanocarriers, site-specific and stimuli specific delivery, are being used. In this review, we discuss the challenges to the oral delivery of peptides and the approaches used to tackle these challenges.

Highly stretchable and tough alginate-based cyclodextrin/Azo-polyacrylamide interpenetrating network hydrogel with self-healing properties

Most structural self-healing materials were developed based on either reversible supramolecular interaction or dynamic covalent bonding. It seems a good idea to incorporate self-healing properties into high-performance materials. In this study, we fabricated the alginate-based cyclodextrin and polyacrylamide azobenzene highly stretchable and tough interpenetrating composite hydrogel with self-repairing behavior under light irradiation. Initially, the alginate-based cyclodextrin and polyacrylamide azobenzene were designed and synthesized. The corresponding structural, thermal, and morphological properties of hydrogels were characterized. The reversible transformation of the sol-gel can be achieved by the irradiation upon ultraviolet light and visible light. The self-healing behavior of this composited gel is based on the host-guest interaction between cyclodextrin and azobenzene. The recovery gel elongation at 48 h healing in the dark condition was is 0.04 MPa, with an elongation of 1140 %. Therefore, this gel can achieve self-healing ability while maintaining highly stretchable and tough performance.

Nanocurcumin: A Promising Candidate for Therapeutic Applications

Curcuma longa is an important medicinal plant and a spice in Asia. Curcumin (diferuloylmethane) is a hydrophobic bioactive ingredient found in a rhizome of the C. longa. It has drawn immense attention in recent years for its variety of biological and pharmacological action. However, its low water solubility, poor bioavailability, and rapid metabolism represent major drawbacks for its successful therapeutic applications. Hence, researchers have attempted to enhance the biological and pharmacological activity of curcumin and overcome its drawbacks by efficient delivery systems, particularly nanoencapsulation. Research efforts so far and data from the available literature have shown a satisfactory potential of nanorange formulations of curcumin (Nanocurcumin), it increases all the biological and pharmacological benefits of curcumin, which was not significantly possible earlier. For the synthesis of nanocurcumin, an array of techniques has been developed and each technique has its own advantages and individual characteristics. The two most popular and effective techniques are ionic gelation and antisolvent precipitation. So far, many curcumin nanoformulations have been developed to enhance curcumin delivery, thereby overcoming the low therapeutic effects. However, most of the nanoformulation of curcumin remained at the concept level evidence, thus, several questions and challenges still exist to recommend the nanocurcumin as a promising candidate for therapeutic applications. In this review, we discuss the different curcumin nanoformulation and nanocurcumin implications for different therapeutic applications as well as the status of ongoing clinical trials and patents. We also discuss the research gap and future research directions needed to propose curcumin as a promising therapeutic candidate.

Understanding the Significance of Microwave Radiation for the Graft Copolymerization of Acrylamide on Carboxymethyl Xanthan Gum

Background:

Nowadays, microwave assisted techniques are becoming popular ecofriendly approaches in Green Chemistry. However, to date, no study has reported the microwave assisted graft copolymerization of acrylamide on carboxymethyl xanthan gum backbone.

Objective:

The objective of this study was to study the effect of microwave radiations on graft copolymerization of acrylamide on carboxymethyl xanthan gum.

Methods:

Carboxymethyl xanthan gum was grafted with acrylamide under microwave irradiation. The grafting process is optimized by varying the amount of carboxymethyl xanthan gum, acrylamide, ammonium persulphate, microwave power and exposure time. The graft copolymer was further characterized and evaluated for its efficacy.

Results:

Grafting was successfully optimized for higher grafting efficiency (92.4 %) and grafting (410.5 %) in a short reaction time of 150 s, at 40 times less concentration of ammonium persulphate. The characterization study confirmed the grafting of acrylamide on the hydroxyl group of carboxymethyl xanthan gum backbone.

Conclusion:

Microwave radiations play a vital role in graft copolymerization of acrylamide on carboxymethyl xanthan gum, in short reaction time, at 40 times less concentration of initiator. The synthesized graft copolymers remain nontoxic and also showed more antimicrobial activity than carboxymethyl xanthan gum.

Assembly of Polyacrylamide-Sodium Alginate-Based Organic-Inorganic Hydrogel with Mechanical and Adsorption Properties

Hydrogels have been widely used in water purification. However, there is not much discussion and comparison about the effects of different nanofillers on the reinforcement and adsorption performances of hydrogels, which can be subjected to rapid water flow and possess strong adsorption ability. In this work, polyacrylamide (PAAM)-sodium alginate (SA) interpenetrating polymer network-structured hydrogels were prepared by in situ polymerization. PAAM formed the first flexible network and SA constructed the second rigid network. Three kinds of inorganic nanoparticles including carbon nanotubes (CNTs), nanoclays (NCs), and nanosilicas (NSs) were incorporated into a PAAM-SA matrix via hydrogen bond. The obtained hydrogels exhibited a macroporous structure with low density (≈1.4 g/cm³) and high water content (≈83%). Compared with neat PAAM-SA, the hydrogels with inorganic nanoparticles possessed excellent mechanical strengths and elasticities, and the compression strength of PAAM-SA-NS reached up to 1.3 MPa at ε = 60% by adding only 0.036 g NS in a 30 g polymer matrix. However, CNT was the best filler to improve the adsorption capacity owing to its multi-walled hollow nanostructure, and the adsorption capacity of PAAM-SA-CNT was 1.28 times higher than that of PAAM-SA. The prepared hydrogels can be potential candidates for use as absorbents to treat wastewater.

Biological Activity and Pharmacological Application of Pectic Polysaccharides: A Review

Pectin is a polymer with a core of alternating α-1,4-linked d-galacturonic acid and α-1,2-l-rhamnose units, as well as a variety of neutral sugars such as arabinose, galactose, and lesser amounts of other sugars. Currently, native pectins have been compared to modified ones due to the development of natural medicines and health products. In this review, the results of a study of the bioactivity of pectic polysaccharides, including its various pharmacological applications, such as its immunoregulatory, anti-inflammatory, hypoglycemic, antibacterial, antioxidant and antitumor activities, have been summarized. The potential of pectins to contribute to the enhancement of drug delivery systems has been observed.