Amino Acid Inspired Alginate-Based pH Sensitive Polymeric Micelles via Reversible Addition–Fragmentation Chain Transfer Polymerization

Abstract

Biopolymeric micelles derived from bioinspired amphiphilic polymers are drawing noteworthy attention as carriers for hydrophobic drugs since they possess a hydrophobic core and a hydrophilic cell. Herein, a hydrophobic monomer N-Boc glycine-hydroxy methyl methacrylate (Gly-HEMA) has been synthesized by chemical modification of N-Boc glycine. This monomer has further been grafted through reversible addition–fragmentation chain transfer (RAFT) polymerization on the backbone of sodium alginate (hydrophilic) to obtain an amphiphilic copolymer with an attached hydrophobic segment. The controlled polymerization is assessed using advanced polymer chromatographic (APC) analysis with a narrow dispersity. The critical micelle concentration (CMC) of the developed copolymer [i.e., Alg-g-p­(Gly-HEMA)] has been determined by surface tension measurement and photoluminescence (PL) spectroscopic and dynamic light scattering (DLS) analyses. The size and morphology of the developed micelle have been investigated by field emission scanning electron microscopy (FESEM) and high-resolution transmission electron microscopy (HRTEM) analyses, which reveal that the size of the copolymeric micelle is ∼200 nm with a spherical shape. Alg-g-p­(Gly-HEMA) has demonstrated pH-responsive reversible micellization behavior. The process of micellization to phase separation and vice versa can be controlled just by altering the pH. The formed micelle is able to uptake the hydrophobic drug indomethacin (% of loading: ∼34%) and release it in a controlled manner, as apparent from an in vitro study.

Adsorption of Toxic Cd(II) on an Antibacterial Biopolymeric Gel toward Fabrication of a Gel Electrolyte-Based Supercapacitor Device

“…From Figure S12a, Supporting Information it is apparent that the hydrogel is noncytotoxic in nature even after 3 days. The % cell viability decreases with increase in polymer dosage but remains mostly viable with respect to TCP after 72 h, indicating that the hydrogel is noncytotoxic in nature. , …”

“…The % cell viability decreases with increase in polymer dosage but remains mostly viable with respect to TCP after 72 h, indicating that the hydrogel is noncytotoxic in nature. 68,69 2.16. Antibacterial Property.…”

Recent advances in various stimuli-responsive hydrogels: from synthetic designs to emerging healthcare applications

“…At alkaline pH, anionic hydrogels undergo a higher dissociation and exhibit better swelling features than those of neutral media. 67,68…”

“…At alkaline pH, anionic hydrogels undergo a higher dissociation and exhibit better swelling features than those of neutral media. 67,68 (c) Amphoteric polyelectrolytic (ampholytic) hydrogels consisting of both acidic and basic functionalities. Polymeric hydrogel networks that contain both cationic and anionic functionalities together are described as ampholytic hydrogels.…”

Sodium Alginate—Natural Microencapsulation Material of Polymeric Microparticles

“…Being a natural polymer, it can be used to obtain hydrogels (Augst, A.D., et al), polymer films (Ning, H., et al) and polymeric micelles (Manna, K., et al). It can be included in the matrix of micro-/nanocapsulated pharmaceutical forms with controlled release of the type of microspheres, microcapsules, silver polymeric nanoparticles (Gudimalla, A., et al), silicon mesoporous polymeric nanoparticles or when obtaining anticancer dendrimers (Liu, C., et al), etc., because it is biodegraded by the body without producing toxic effects, is biocompatible, can form gels and hydrogels easily, is inert and chemically compatible with many natural/synthetic materials, can be easily synthesized and manipulated and can control the speed of release of active compounds from pharmaceutical systems [ 4 , 105 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 ].…”