Adsorption of Trypsin on Hydrophilic and Hydrophobic Surfaces

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• 作者：Sotirios Koutsopoulos ; Katja Patzsch ; Wouter T. E. Bosker ; Willem Norde
• 刊名：Langmuir
• 出版年：2007
• 出版时间：February 13, 2007
• 年：2007
• 卷：23
• 期：4
• 页码：2000 - 2006
• 全文大小：440K
• 年卷期：v.23,no.4(February 13, 2007)
• ISSN：1520-5827

文摘

The adsorption of trypsin onto polystyrene and silica surfaces was investigated by reflectometry, spectroscopicmethods, and atomic force microscopy (AFM). The affinity of trypsin for the hydrophobic polystyrene surface washigher than that for the hydrophilic silica surface, but steady-state adsorbed amounts were about the same at bothsurfaces. The conformational characteristics of trypsin immobilized on silica and polystyrene nanospheres were analyzedin situ by circular dichroism and fluorescence spectroscopy. Upon adsorption the trypsin molecules underwent structuralchanges at the secondary and tertiary level, although the nature of the structural alterations was different for silicaand polystyrene surfaces. AFM imaging of trypsin adsorbed on silica showed clustering of enzyme molecules. Rinsingthe silica surface resulted in 20% desorption of the originally adsorbed enzyme molecules. Adsorption of trypsin onthe surface of polystyrene was almost irreversible with respect to dilution. After adsorption on silica the enzymaticactivity of trypsin was 10 times lower, and adsorbed on polystyrene the activity was completely suppressed. The trypsinmolecules that were desorbed from the sorbent surfaces by dilution with buffer regained full enzymatic activity.