Synthesis, characterization, and biological activities of folic acid conjugates with polyvinyl alcohol, chitosan, and cellulose

Abstract

Polyvinyl alcohol (PVA), chitosan (CS), and cellulose (CL) are promising polymers for chemical functionalization and biomedical applications. This study aimed to synthesize folic acid (FA) conjugates with PVA, CS, and CL via chloroacetyl chloride, 2-bromopropionyl bromide, and epichlorohydrin to enhance it biomedical applications. The functionalized polymer conjugates were characterized by FT-IR, 1 H-NMR, GPC, and TGA techniques. FT-IR and 1 H-NMR revealed the main functional groups (O H, N H, C═O, C═N), the aromatic C H and N H protons of FA moieties. TGA illustrated two stages of decompositions of all-polymer conjugates. FA showed no antifungal activity, while two of the newly grafted polymer conjugates (chitosan bromopropionate-grafted FA and cellulose chloroacetate-grafted FA) illustrated antifungal activity against both Aspergillus fumigatus and Candida albicans. Polymer conjugates; poly(vinyl chloroacetate)-grafted FA and chitosan-EPCH-grafted FA revealed good antifungal effect on C. albicans and A. fumigatus, respectively. Most FA polymer conjugates showed significant antitumor activity against EAC-bearing mice. Among these conjugates, chitosan chloroacetate-grafted FA (P-2A) showed the highest antitumor effect against EAC-bearing mice via reduction in total tumor volume. Thus, these conjugates provided enhanced antifungal and antitumor activities as compared with FA itself. These conjugates may act as promising biologically active carrier systems for other applications such as drug delivery.

Lignocellulosic–biomolecules conjugated systems: green-engineered complexes modified by covalent linkers

“…For example, ester bonds are formed when C-6 hydroxyl CNC reacts with bromoacetyl bromide; this spacer links several biomolecules through nucleophilic substitution. 84,85 External parameters are essential for some lignocellulosic conjugated formations. For example, temperature plays a crucial role, and molecules like citric acid (CA) may serve as a suitable linker in thermodynamically favourable conditions.…”

“…For example, ester bonds are formed when C-6 hydroxyl CNC reacts with bromoacetyl bromide; this spacer links several biomolecules through nucleophilic substitution. 84,85…”

Synthesis, characterization, and biological activities of new conjugates of Guanosine grafted on polyvinyl alcohol, carbohydrate chitosan, and cellulose

“…The reaction mixture was refluxed for 1 h, cooled, and poured over a large amount of water. The products were filtered off, washed several times with water, and dried at 50 °C for one week [39,40].…”

“…The reaction mixture was warmed at 100 °C for 24 h. The solvent was removed by under vacuum. The resulted polymers were collected, washed several times with acetone/water (5:1), and dried at 50 °C for 4 days [6,39].…”

“…Isoguanosine gel illustrated anticancer activities for a variety of cancer cells with dual-functions such as delivery system and anticancer compound in one system [38]. The chemical grafting of modified PVA, CS, and CL with folic acid by different linkers showed enhancing in the biological applications of folic acid [39]. The novelty of this study was conducted to synthesize, characterize and enhance the biological activities of PVA, CS, and CL via grafting with GU by using different linkers such as chloroacetyl chloride, 2-bromopropionyl bromide, and EPCH.…”