Biodegradable, pH‐Responsive Carboxymethyl Cellulose/Poly(Acrylic Acid) Hydrogels for Oral Insulin Delivery

Abstract

Biodegradable and pH-responsive carboxymethyl cellulose/poly(acrylic acid) hybrid hydrogels are synthesized. The hydrogels deswell in acidic artificial gastric fluid (AGF) but rapidly swell in neutral artificial intestinal fluid (AIF), rendering selective enzymatic degradation of the gels as well as accelerated drug release from insulin-loaded hydrogels in AIF. Oral administration of insulin-loaded hydrogels to streptozotocin-induced diabetic rats leads to a continuous decline in the fasting blood glucose level within 6 h post-administration, and the relative pharmacological availability increases more than 10 times compared to oral administration of free insulin solution. The relative bioavailability of hydrogel-encapsulated insulin after oral administration to healthy rabbits is 6.6%.

pH‐Responsive Drug‐Delivery Systems

“…Gao et al [13] prepared biodegradable and pH-responsive carboxymethyl cellulose/poly(acrylic acid) hybrid hydrogels, which deswelled in acidic artificial gastric fluid but rapidly swelled in neutral artificial intestinal fluid, and exhibited selective enzymatic degradation of the gels and accelerated drug release from insulin-loaded hydrogels in artificial intestinal fluid. Oral administration of insulin-loaded hydrogels to streptozotocin-induced diabetic rats led to a continuous decline in the fasting blood glucose level within 6 h post-administration, and the relative pharmacological availability increased more than 10 times compared with oral administration of a solution of free insulin.…”

A composite hydrogel system containing glucose-responsive nanocarriers for oral delivery of insulin

“…This special structure can be utilized as a pH shift between the stomach and intestine environmental to induce release of insulin from nanocarriers. [39,40] The cross-linking agent, EGDMA, is used to stabilize the nanocarriers and prevent the rapid release of insulin. Folic acid (FA) is an attractive targeting agent to many cell types that over express the folate receptors (FR).…”

Bio-waste derived dialdehyde cellulose ethers as supports for α-chymotrypsin immobilization

“…AIF was prepared by dissolving potassium dihydrogen phosphate (6.8 g) in 500 mL of the deionized water, and the pH was then adjusted to 6.8 and the solution was then diluted to 1000 mL by addition of the deionised water [37].…”