Assembly-controlled biocompatible interface on a microchip: strategy to highly efficient proteolysis.

Yun Liu; Wei Zhong; Sheng Meng; Jilie Kong; Haojie Lu; Pengyuan Yang; Hubert H Girault; Baohong Liu

doi:10.1002/chem.200501622

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Assembly-controlled biocompatible interface on a microchip: strategy to highly efficient proteolysis.

Yun Liu·Wei Zhong·Sheng Meng·Jilie Kong·Haojie Lu·Pengyuan Yang·Hubert H Girault·Baohong Liu

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Abstract

A biocompatible interface was constructed on a microchip by using the layer-by-layer (LBL) assembly of charged polysaccharides incorporating proteases for highly efficient proteolysis. The controlled assembly of natural polyelectrolytes and the enzyme-adsorption step were monitored by using a quartz-crystal microbalance and atomic force microscopy (AFM). Such a multilayer-assembled membrane provides a biocompatible interconnected network with high enzyme-loading capacity. The maximum digestion rate of the adsorbed trypsin in a microchannel was significantly accelerated to 1600 mM min(-1) microg(-1), compared with the tryptic digestion in solution. Based on the Langmuir isotherm model, the thermodynamic constant of adsorption K was calculated to be 1.6 x 10(5) M(-1) and the maximum adsorption loading Gammamax was 3.6 x 10(-6) mol m(-2), 30 times more than a monolayer of trypsin on the native surface. The tunable interface containing trypsin was employed to construct a microchip reactor for digestion of femtomoles of proteins and the produced peptides were analyzed by MALDI-TOF mass spectroscopy. The efficient on-chip proteolysis was obtained within a few seconds, and the identification of biological samples was feasible.

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Biocompatible Materials Biosensing Techniques Caseins Chitosan Enzymes, Immobilized Hepatitis A Vaccines Hyaluronic Acid Hydrophobic and Hydrophilic Interactions Kinetics Microfluidic Analytical Techniques Microscopy, Atomic Force Peptides Protein Array Analysis Proteomics Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization Trypsin Journal Article Research Support, Non-U.S. Gov't

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Yun Liu, Wei Zhong, Sheng Meng, Jilie Kong, Haojie Lu, Pengyuan Yang, Hubert H Girault, Baohong Liu. 2006-08-25. Assembly-controlled biocompatible interface on a microchip: strategy to highly efficient proteolysis.. https://doi.org/10.1002/chem.200501622

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