An immunosensor based on the glucose oxidase label and optical oxygen detection.
A novel optical immunosensor setup is described which uses glucose oxidase enzyme as a label in conjunction with a luminescence lifetime-based oxygen sensor and phase measurements. The oxygen sensor membranes prepared on microporous filters were used as a solid phase on which the immunoassay was carried out. These sensing materials in combination with a new measurement setup provided high sensitivity for the detection of oxidase enzymes, being at nanogram per milliliter level, i.e., 10(-11)-10(-12) M, with respect to glucose oxidase and its conjugates. Experimental data on the sensitivity were validated using theoretical equations and calculations. Using the new measurement setup and IgG-anti-IgG as a model, a number of different sensing materials were studied aimed to optimize the immunosensor and evaluate its performance. This approach was then applied to a practical system for the detection of human lactate dehydrogenase isoenzymes. It provided similar sensitivity of approximately 1 ng/mL, which is comparable to that of standard ELISA. The attributes of the new immunosensor approach are discussed with respect to performance and versitility.
Papkovsky
D B
DB
Biochemistry Department, National University of Ireland, Cork, Ireland. dbp@ucc.ie
O'Riordan
T C
TC
Guilbault
G G
GG
D015374:Biosensing Techniques; D005949:Glucose Oxidase / Q000737:chemistry*; D006801:Humans; D007120:Immunochemistry; D010100:Oxygen / Q000032:analysis*
D005949:Glucose Oxidase; D010100:Oxygen