Structure and protein separation efficiency of poly(N-isopropylacrylamide) gels: Effect of synthesis conditions

Kayaman N., Kazan D., Erarslan A., Okay O., Baysal B.

JOURNAL OF APPLIED POLYMER SCIENCE, cilt.67, sa.5, ss.805-814, 1998 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 67 Sayı: 5
  • Basım Tarihi: 1998
  • Dergi Adı: JOURNAL OF APPLIED POLYMER SCIENCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.805-814
  • Anahtar Kelimeler: poly(N-isopropylacrylamide), temperature-sensitive gels, gel swelling, protein separation efficiency, gel extraction, TEMPERATURE-SENSITIVE HYDROGEL, PHASE-TRANSITION, POLYACRYLAMIDE GELS, POLYMER NETWORKS, SALT-SOLUTIONS, COLLAPSE, WATER, CYCLIZATION, EXTRACTION, ASSAY
  • Marmara Üniversitesi Adresli: Hayır

Özet

Crosslinked poly(N-isopropylacrylamide) (PNIPA) gels with different crosslink densities in the form of rods and beads were prepared by free-radical crosslinking copolymerization. Solution and inverse suspension polymerization techniques were used for the gel synthesis. The gels were utilized to concentrate dilute aqueous solutions of penicillin G acylase (PGA), bovine serum albumin (BSA), and 6-aminopenicillanic acid (6-APA). The discontinuous volume transition at 34 degrees C observed in the gel swelling was used as the basis of concentrating dilute aqueous protein solutions. PNIPA gels formed below 18 degrees C were homogeneous, whereas those formed at higher temperatures exhibited heterogeneous structures. The water absorption capacity of PNIPA gels in the form of beads was much higher, and their rate of swelling was much faster than the rod-shaped PNIPA gels. It was also found that the polymerization techniques used significantly affect the properties of PNIPA gels. The separation efficiency decreased when the protein molecules PGA or BSA in the external solution were replaced with small-molecular-weight compounds, such as 6-APA. The protein separation efficiency by the gel beads increased to 100% after coating the bead surfaces with BSA. (C) 1998 John Wiley & Sons, Inc.