Positively and Negatively Charged Collagen Nanohydrogels: pH‐responsive Drug‐releasing Characteristics

Abstract

Researchers are facing many challenges in developing a strategy for site‐specific delivery in the gastrointestinal tract that can maximize therapeutic response and reduce side effects. The objective of this article was to develop a site‐specific drug delivery system for the gastrointestinal tract using natural polymer collagen (CG). For this, two types of pH‐responsive CG nanohydrogels (negatively charged pH‐CGNH‐COOH and positively charged pH‐CGNH‐NH2) were prepared using negatively and positively functionalized carbon nanotubes, CNT‐COOH and CNT‐NH2, respectively. The pH‐CGNH‐COOH and pH‐CGNH‐NH2 nanohydrogel samples comprising negatively and positively charged fibrils (CG/CNT‐COOH and CG/CNT‐NH2) were physicochemically characterized by Fourier‐transform infrared spectrometry, Zeta sizer, thermogravimetric analysis, and field emission scanning electron microscopy. They also revealed the pH‐responsive release of bovine serum albumin at pH 9 and cytochrome C at pH 2. These results strongly indicate that these drug carriers can be useful for site‐specific delivery in the gastrointestinal tract.

Improved Solubility and Activity of Natural Product in Nanohydrogel

“…Nanohydrogel is a more modern drug delivery system that controls drug release to improve pharmacological activity. Nanohydrogel carrier systems derived from natural materials can deliver drugs at an increased rate according to the body's needs during the treatment period and deliver active compounds from the preparation to the site of drug action quickly [31,32]. These findings show that when using a single pure compound, the solubility is worse in water than in the nanohydrogel dosage form, which is very soluble in water.…”