title: Microfluidic devices integrating microcavity surface-plasmon-resonance sensors: glucose oxidase binding-activity detection.
abstract: We have developed miniature (approximately 1 microm diameter) microcavity surface-plasmon-resonance sensors (MSPRS), integrated them with microfluidics, and tested their sensitivity to refractive-index changes. We tested their biosensing capability by distinguishing the interaction of glucose oxidase (M(r) 160 kDa) with its natural substrate (beta-D-glucose, M(r) 180 Da) from its interactions with nonspecific substrates (L-glucose, D-mannose, and 2-deoxy-D-glucose). We ran the identical protocol we had used with the MSPRS on a Biacore 3000 instrument using their bare gold chip. Only the MSPRS was able to detect beta-D-glucose binding to glucose oxidase. Each MSPRS can detect the binding to its surface of fewer than 35,000 glucose oxidase molecules (representing 9.6 fg or 60 zmol of protein), about 10(6) times fewer than classical surface-plasmon-resonance biosensors.
authors.affiliation: Biocomplexity Institute, Department of Physics, Indiana University, Bloomington, Indiana 47405-7102, USA. damarie@indiana.edu
authors.forename: Dragos
authors.initials: D
authors.lastname: Amarie
authors.forename: Abdelkrim
authors.initials: A
authors.lastname: Alileche
authors.forename: Bogdan
authors.initials: B
authors.lastname: Dragnea
authors.forename: James A
authors.initials: JA
authors.lastname: Glazier
mesh_terms: D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D011485:Protein Binding; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods*
chemical_list: D005949:Glucose Oxidase