Photodiode array on-chip biosensor for the detection of E. coli O157:H7 pathogenic bacteria.
An integrated circuit (IC) of photodiode array (PDA) microchip system was used for the on-chip detection of E. coli O157:H7 based on an enzymatic bioassay and light absorption property of the reaction product. The PDA microchip consisting of an array of 12 x 12 photodiode detection elements served as a photosensor as well as a protein-immobilizing sample platform. As a result, E. coli O157:H7 could be detected directly on the surface of PDA detection elements. E. coli O157:H7 was detected by forming a "sandwich-type" enzymatic immunocomplex on the PDA detection elements using an on-chip bioassay. The quantitative analysis of E. coli O157:H7 immunocomplex was carried out based on the light absorption property of the enzymatic reaction products of E. coli O157:H7 immunocomplexes with respect to a red beam produced by light emitting diodes (LEDs) installed right above the PDA microchip. During the on-chip bioassay, the wet photodiode detection elements exposed to a lot of biological materials or buffer solutions were capable of maintaining their photosensing capabilities. The portable PDA on-chip biosensor permits direct optical detection of E. coli O157:H7 and eliminates the necessity of the conventional expensive microplate reader that is incompatible with the size of the protein microarray.
Song
Joon Myong
JM
Research Institute of Pharmaceutical Sciences and College of Pharmacy, Seoul National University, Seoul, South Korea.
Kwon
Ho Taik
HT
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D015169:Colony Count, Microbial / Q000295:instrumentation* / Q000379:methods; D004581:Electronics / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D019453:Escherichia coli O157; D046228:Microarray Analysis / Q000295:instrumentation* / Q000379:methods; D010783:Photometry / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012666:Semiconductors; D012680:Sensitivity and Specificity