Insulin release from islets of Langerhans entrapped in a poly(N-isopropylacrylamide-co-acrylic acid) polymer gel

Brent Vernon, Sung Wan Kim, You Han Bae

Research output: Contribution to journalArticle

61 Citations (Scopus)

Abstract

A copolymer of N-isopropylacrylamide (98 mol% in feed) and acrylic acid, poly(N-isoplopylacrylamide-co-acrylic acid) (P(NIPAAm-co-AAc)), was prepared by free radical polymerization for development of a thermally reversible polymer to entrap islet of Langerhans for a refillable biohybrid artificial pancreas. A 5 wt% solution of the polymer in Hanks' balanced salt solution forms a gel at 37°C that exhibits no syneresis. Diffusion of fluorescein isothiocyanate (FITC) dextrans having molecular weights of 4400 and 70 000 were used to evaluate mass transport in the gel at 37°C. Insulin secretion from islets in the polymer gel was also investigated in both static and dynamic systems. The polymer gel exhibited excellent diffusion of FITC dextran 4400 and FITC dextran 70 000 with diffusion ratios. D/D0 (ratio of diffusion in the gel to diffusion in water), of 0.20 ± 0.04 and 0.35 ± O.17, respectively. Human islets entrapped in the polymer gel showed prolonged insulin secretion in response to basal (5.5 mM) glucose concentration compared to free human islets. Rat islets showed prolonged insulin secretion in response to high (16.5 mM) glucose concentrations compared to free rat islets. Rat islets in the polymer gel maintained insulin secretion in response to the higher glucose concentration for over 26 days. Rat islets entrapped by the polymer also released higher quantities of insulin more rapidly in response to changes in concentrations of glucose and other stimulants than rat islets entrapped in an alginate control. These results suggest that this material would provide adequate diffusion for rapid insulin release in an application as a synthetic extracellular matrix for a biohybrid artificial pancreas.

Original languageEnglish (US)
Pages (from-to)183-198
Number of pages16
JournalJournal of Biomaterials Science, Polymer Edition
Volume10
Issue number2
StatePublished - 1999
Externally publishedYes

Fingerprint

carbopol 940
Insulin
Islets of Langerhans
Acrylics
Polymers
Gels
Rats
Acids
Glucose
Dextran
Artificial Pancreas
Alginate
Free radical polymerization
poly-N-isopropylacrylamide
Dextrans
Polymerization
Free Radicals
Extracellular Matrix
Dynamical systems

Keywords

  • Biohybrid pancreas
  • Insulin secretion
  • Islets of Langerhans
  • Poly(N-isopropylacrylamide-co-acrylic acid)

ASJC Scopus subject areas

  • Biophysics

Cite this

Insulin release from islets of Langerhans entrapped in a poly(N-isopropylacrylamide-co-acrylic acid) polymer gel. / Vernon, Brent; Kim, Sung Wan; Bae, You Han.

In: Journal of Biomaterials Science, Polymer Edition, Vol. 10, No. 2, 1999, p. 183-198.

Research output: Contribution to journalArticle

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