SYNTHESIS AND APPLICATION OF DERIVATIZED NATURAL GUM BASED HYDROGELS

Abstract

Regulating the release of drugs with safety, effectiveness, and consistency is one major problem in healthcare systems. The use of natural gum-based hydrogels for drug delivery and wound healing may be the best solution to this problem. These hydrogels, derived from natural sources such as gum tragacanth, locust bean gum offer several advantages over synthetic hydrogels, including better biocompatibility and a homogeneous polymer network. With their biocompatible, biodegradable, and non-cytotoxic properties, natural gum-based hydrogels are ideal candidates for drug delivery and wound healing applications. They can efficiently encapsulate and release therapeutic agents, such as antibiotics or growth factors, in a controlled manner, promoting wound healing and preventing infection. Furthermore, the three-dimensional structure of hydrogels allows for the diffusion of nutrients and oxygen to the wound site, facilitating tissue regeneration and reducing healing time. In conclusion, natural gum-based hydrogels have shown great potential in drug delivery and wound healing applications. In this thesis, some novel hydrogels were synthesized as the carriers for drug delivery and wound healing. The first approach was the fabrication of the Carboxymethylated Gum Tragacanth (CMGT) based hydrogel and its application as a drug delivery carrier. For the fabrication of CMGT cross-linked Sodium Acrylate Hydrogel (CMGT-co SAH), firstly carboxymethylation of the Gum Tragacanth (GT) was done followed by synthesis of the CMGT-co-SAH by free radical co-polymerisation technique and confirmed by the characterization- FTIR, XRD, TGA, SEM and C13 -NMR. Flow properties of the hydrogel were analyzed by rheological analysis by viscosity, amplitude and frequency sweep test. By using Flory-Rehner equation, network parameter xiv of the hydrogel was analyzed that support the results of swelling index. Application of CMGT-co-SAH as the drug delivery carrier was analyzed by using the Aceclofenac Sodium (AFS) as a model drug. AFS loading and release profile were analyzed in pH 7.4 at 37 °C. Kinetic models were applied over the release profile of the AFS and follows the fickian diffusion mechanism and fitted in the Korsmeyer-Peppas model. Moreover, synthesized CMGT-co-SAH shows less than 1% hemolysis at every concentration that confirms the cyto-compatability of the CMGT-co-SAH. Second approach includes Synthesis and Characterization of Carboxymethylated Locust Bean Gum (CMLB) based pH Responsive Hydrogel, (CMLB-co-poly(SA)-cl poly(MBA) for Controlled Drug Delivery of Metformin Hydrochloride (MFH). The confirmation of successful carboxymethylation and hydrogel synthesis is achieved through a comprehensive characterization process employing FTIR, XRD, TGA, SEM, and C13-NMR techniques. Rheological analysis, including viscosity, amplitude, and frequency sweep tests, provides insights into the flow properties of the hydrogel in three different solutions, i.e., Distilled water, pH 7.4, and pH 2.2 buffer solutions. The Flory Rehner equation is employed to analyze the network parameters of the hydrogel. Furthermore, we explore the application of the hydrogel as a drug delivery carrier which shows a sustainable release of MFH in Distilled water, pH 7.4, and pH 2.2 buffer solutions. The drug loaded CMLB-co-poly(SA)-cl-poly(MBA) hydrogel followed the non-fickian diffusion mechanism. The biocompatibility of the above two synthesized hydrogels was assessed through hemolysis studies. Last approach includes the synthesis of a novel hydrogel film based on carboxymethylated gum cross-linked with Citric Acid (CA) loaded with Cassia fistula essential oils (EO) that xv are Rosemary essential oil (REO) (Rosmarinus officinalis), Turmeric essential oil (TEO) (Curcuma longa) and Thuja essential oil (THEO) (Thuja occidentalis L.) for wound healing application as these essential oils have anti-microbial, anti-inflammatory, antioxidant, and analgesic properties. Moreover, thermal analysis (TGA), structural characteristics (FTIR and XRD), morphology (SEM), mechanical strength, anti-oxidant activity, bio degradability test, permeability test and cytotoxicity assay (in vitro and in vivo) were analyzed for the films. From the performed tests and assay, we concluded that the film can be an effective, biocompatible and biodegradable source of wound healing films. Overall, the utilization of natural gum-based hydrogels for drug delivery and wound healing represents a promising approach that has the potential to revolutionize current treatment protocols and enhance patient care.