Controlled release by using poly (methacrylic acid-g-ethylene glycol ) hydrogels

نویسندگان

  • Nikolaos A. Peppas
  • John Klier
چکیده

Graft copolymers of poly (ethylene glycol) with poly (methacrylic acid) were prepared by reaction of poly (ethylene glycol) methacrylate macromonomer with methacrylic acid in the presence of tetraethylene glycol dimethacrylate as a crosslinking agent. The materials were swollen in aqueous solutions with the pH ranging from 1.5 to 12.0. Dynamic swelling studies were performed. The swelling rates were lowest in copolymer networks with 1: 1 ratios of ethylene oxide to methacrylic acid. These results were attributed to the combined effects of diffusion and complex dissociation during swelling. Solute release studies were carried out to investigate the effect of pH and swelling on the release behavior. Lowest solute release rates were observed in complex-forming networks, verifying the relationship between complexation, swelling and solute permeability.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Swelling behavior and release properties of pH-sensitive hydrogels based on methacrylic derivatives.

The purpose of this study is to develop novel intestinal-specific drug delivery systems with pH sensitive swelling and drug release properties. Methacrylic-type polymeric prodrugs were synthesized by free radical copolymerization of methacrylic acid, poly(ethyleneglycol monomethyl ether methacrylate) and a methacrylic derivative of N-(4-hydroxyphenyl)-2-(4-methoxyphenyl) acetamide in the presen...

متن کامل

Oral insulin delivery using P(MAA-g-EG) hydrogels: effects of network morphology on insulin delivery characteristics.

Hydrogels of poly(methacrylic acid-g-ethylene glycol) were prepared using different reaction water contents in order to vary the network mesh size, swelling behavior and insulin loading/release kinetics. Gels prepared with greater reaction solvent contents swelled to a greater degree and had a larger network mesh size. All of the hydrogels were able to incorporate insulin and protected it from ...

متن کامل

Water, solute and protein diffusion in physiologically responsive hydrogels of poly (methacrylic acid-g-ethylene glycol).

Grafted poly (methacrylic acid-g-ethylene glycol) [P(MAA-g-EG)] copolymers were synthesized and their pH sensitivity was investigated. P(MAA-g-EG) membranes showed pH sensitivity due to complex formation and dissociation. Uncomplexed equilibrium swelling ratios were 40 to 90 times higher than those of the complexed states and varied according to copolymer composition and poly(ethylene glycol) (...

متن کامل

Loading and mobility of spin-labeled insulin in physiologically responsive complexation hydrogels intended for oral administration.

Poly(methacrylic acid-g-ethylene glycol) copolymers are pH-responsive complexation hydrogels that have shown promise in in vitro and in vivo results as oral insulin delivery carriers. With the aim of gaining more detailed insight into their performance to further improve the carriers, we spin-labeled insulin and used electron spin resonance (ESR) spectroscopy to follow the loading of the spin-l...

متن کامل

Gastrointestinal transit and mucoadhesive characteristics of complexation hydrogels in rats.

The aim of this study was to investigate the gastrointestinal (GI) transit and mucoadhesive properties of complexation hydrogels, poly(methacrylic acid-grafted-ethylene glycol). The fluorescent labeled complexation hydrogels containing different molar ratios of methacrylic acid/ethylene glycol and different particle diameters were synthesized by free radical solution polymerization. The GI tran...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1990