Rheological behavior of pH responsive composite hydrogels of chitosan and alginate: Characterization and its use in encapsulation of citral

Pink grapefruit lycopene encapsulated in alginate‐based beads: stability towards freezing and drying

“…On the other hand, beads containing chitosan were worse than those obtained using only trehalose (A-T beads) and were even comparable to A-beads (without excipients) subjected to f/t. Due to its cationic characteristics, chitosan interacts with alginate contributing to the Ca(II)-alginate network, giving helpful barrier properties and mechanical strength (Santagapita et al, 2012;Afzal et al, 2018). However, the generation of this interaction produced negative effects on the emulsifying properties of the alginate droplets and therefore emulsions were destabilised, leaving the encapsulated lycopene unprotected.…”

A comprehensive review of the structures and properties of ionic polymeric materials

“…For instance, Afzal et al studied the impact of pH on the rheological properties of chitosan/alginate hydrogels. 119 At pH values comprised between the pK a s of polymers (4 < pH < 6), full ionization of amine and carboxylic acid occurs and leads to highest viscosities and moduli, while pH > 6 leads to increased brittleness. Moreover, it is possible to tune the softness and brittleness of these ionic hydrogels by changing alginate and chitosan concentrations.…”

“…187 It is worth mentioning that ionic hydrogels are well-used in biomedical applications as they show biocompatibility, low cytotoxicity and antimicrobial properties. One of the most promising pathways for application of ionic polymeric materials in the biomedical fields regroups drug, 119,188,189 gene, 190,191 nucleic acid 192 and protein 193 delivery. Incorporating a zwitterionic sequence within polypeptides, 194 adding phosphonium groups into PEG-based hydrogels, 195 or functionalizing chitosan-PEG nanoparticles 196 are among recent strategies to design drug delivery systems.…”

Development and characterization of controlled released polyphenol rich micro‐encapsulate ofMurraya koenigiibark extract

“…However, chitosan helps in stronger adhesion to ileum in intestines with simultaneous increase in pH, thereby, helps in release of entrapped phenolics in the intestines (Onuigbo, Onugwu, Nwocha, Odiase, & Attama, 2016). These hydrogels have been reported for high strengthening at low pH and easy dissociation at higher pH (Afzal, Maswal, & Dar, 2018). Since, the pH of intestines is high, thus, dissociation of beads would be easy, which finally leads to the increased availability and efficiency of hydrogel bound phenolics in the intestine.…”