Improving delivery of hydrophobic drugs from hydrogels through cyclodextrins

Abstract

A simple and effective technique of improving delivery of hydrophobic drugs from swellable systems is presented. Conventional methods of drug loading in hydrogel systems are limited by the characteristics of the pharmacological agent. The approach we present uses complexants to modulate drug release. Crosslinked poly(ethylene glycol) (PEG) hydrogels were synthesized, characterized, and used for vascular applications. The release of cyclosporine (CyA) from PEG hydrogels is significantly altered by the sterilization techniques. It was hypothesized that the release of CyA from PEG hydrogels can be modulated by using complexants. A cyclodextrin-CyA complex solution was prepared and used for drug loading. The sterilized PEG hydrogels that were loaded using the cyclodextrin-CyA complex solution had favorable release characteristics compared with the release from PEG hydrogels that were loaded using the conventional technique. Hence, drug release from swellable systems can be tailored by the application of this strategy.

New Cyclodextrin Hydrogels Cross-Linked with Diglycidylethers with a High Drug Loading and Controlled Release Ability

“…This type of hydrogel has been shown useful in developing drug delivery systems to administer the drug by different routes, e.g., oral, buccal, or transdermal, minimizing adverse side effects and improving the pharmacological effects (21). Compared to other approaches that require the use of organic solvents and sophisticated carriers, the preparation of cyclodextrin hydrogels involves simpler technological processes, which are foreseeable to be easy to scale-up, and more biocompatible and stable materials (20,21).…”

“…These hydrogels showed a pH-dependent release rate, which is given by the maleic groups of the "CD monomer (17). Cyclodextrin hydrogels can be also obtained by using cross-linking agents able to react with their hydroxyl groups (20,24,25). Unmodified "CD and poly(vinyl alcohol) were cross-linked with epichlorohydrin to obtain hydrogels able to load and sustain the release of salicylic acid (25).…”

A Review on Recent Advances in Stabilizing Peptides/Proteins upon Fabrication in Hydrogels from Biodegradable Polymers

“…Due to its high water content, it retains the activity of proteins and protects from denaturation thus making it ideal encapsulation and release material for proteins. Hydrogels serve as ideal drug delivery systems with desirable therapeutic features [159].They have excellent physicochemical and biological properties with a wide diversity of polymeric materials which lead to excellent candidates for delivery systems of pharmaceutical agents [160][161][162]. Pharmaceutical hydrogels have various categories based on different criteria mainly including, route of administration [163,164], type of material therapeutic agent to be delivered [25,135,163], and release profile [165,166].…”

Improvements in Topical Ocular Drug Delivery Systems: Hydrogels and Contact Lenses

“…Kanjickal et al observed a favorable release kinetic when a CD-cyclosporine inclusion complex for drug loading in a poly (ethylene glycol) hydrogel was used (33). In the development and formulation of hydrogels, CDs play multiple roles such as crosslinking agents, conveying peculiar structural and physicochemical properties to the matrix, and interacting by means of inclusion complexes with lipophilic drugs.…”