Preparation of dual temperature/pH-sensitive polyampholyte gels and investigation of their protein adsorption behaviors

作者：Kanazawa Ryoichi; Sasaki Aika; Tokuyama Hideaki^*

来源：Separation and Purification Technology, 2012, 96: 26-32.

DOI：10.1016/j.seppur.2012.05.016

• N-isopropylacrylamide
• Temperature/pH-sensitive gel
• Polyampholyte gel
• Adsorption
• Bovine serum albumin

Dual temperature/pH-sensitive polyampholyte gels were developed for use as adsorbents and carriers that deal with organic electrolytes such as proteins. NIPA-co-DMAPAA-co-AA gels were prepared by copolymerizing N-isopropylacrylamide (NIPA) as a thermosensitive component with N,N-dimethylaminopropylacrylamide (DMAPAA) as a weakly-basic cation-comonomer, acrylic acid (AA) as a weakly-acidic anion-comonomer, and N,N%26apos;-methylenebisacrylamide (MBAA) as a cross-linker, and their thermosensitive and pH-sensitive swelling properties and protein adsorption properties were investigated. The gel adsorbed bovine serum albumin (BSA) applied as a model protein at pH values in the range of 4.5-10 and 25 degrees C as a result of the electrostatic interactions. In addition, the pre-adsorbed BSA was well desorbed from the gel at pH values less than 4 or greater than 11. The pH-sensitivity of the adsorption is found to be based on the protonation of amino groups in DMAPAA and dissociation of carboxyl groups of AA. The BSA adsorption was investigated as a function of MBAA concentration and temperature, and was discussed in terms of the difference in the sizes of the BSA molecule and gel network.

• 出版日期2012-8-21