Detection of analyte binding to microarrays using gold nanoparticle labels and a desktop scanner.

Microarray hybridization or antibody binding can be detected by many techniques, however, only a few are suitable for widespread use since many of these detection techniques rely on bulky and expensive instruments. Here, we describe the usefulness of a simple and inexpensive detection method based on gold nanoparticle labeled antibodies visualized by a commercial, office desktop flatbed scanner. Scanning electron microscopy studies showed that the signal from the flatbed scanner was proportional to the surface density of the bound antibody-gold conjugates, and that the flatbed scanner could detect six attomoles of antibody-gold conjugates. This detection system was used in a competitive immunoassay to measure the concentration of the pesticide metabolite 2,6-dichlorobenzamide (BAM) in water samples. The results showed that the gold labeled antibodies functioned comparably with a fluorescent based immunoassay for detecting BAM in water. A qualitative immunoassay based on gold-labeled antibodies could determine if a water sample contained BAM above and below 60-70 ng L(-1), which is below the maximum allowed BAM concentration for drinking water (100 ng L(-1)) according to European Union legislation.

[1]  M. Jakobsen,et al.  New monoclonal antibody for the sensitive detection of hydroxy-s-triazines in water by enzyme-linked immunosorbent assay. , 2000 .

[2]  Michael J. Natan,et al.  Kinetic Control of Interparticle Spacing in Au Colloid-Based Surfaces: Rational Nanometer-Scale Architecture , 1996 .

[3]  D Rodbard,et al.  Statistical quality control and routine data processing for radioimmunoassays and immunoradiometric assays. , 1974, Clinical chemistry.

[4]  J. Slot,et al.  A new method of preparing gold probes for multiple-labeling cytochemistry. , 1985, European journal of cell biology.

[5]  A. Schuurs,et al.  Optimization of a sandwich sol particle immunoassay for human chorionic gonadotrophin. , 1983, Journal of immunological methods.

[6]  M. Christiansen,et al.  Characterization of monoclonal antibodies raised against different structures belonging to the s-triazine group of herbicides , 2001 .

[7]  C. Mirkin,et al.  Scanometric DNA array detection with nanoparticle probes. , 2000, Science.

[8]  C. Cremisini,et al.  Dipstick immunoassay format for atrazine and terbuthylazine analysis in water samples , 1998 .

[9]  W. D. Geoghegan,et al.  Passive gold agglutination. An alternative to passive hemagglutination. , 1980, Journal of immunological methods.

[10]  N. Cuong,et al.  Development of a dipstick immunoassay for quantitative determination of 2,4-dichlorophenoxyacetic acid in water, fruit and urine samples , 1999 .

[11]  Barry Schweitzer,et al.  Measuring proteins on microarrays. , 2002, Current opinion in biotechnology.

[12]  M. Jakobsen,et al.  A quantitative enzyme-linked immunoassay for the detection of 2, 6-dichlorobenzamide (BAM), a degradation product of the herbicide dichlobenil. , 2000, JIM - Journal of Immunological Methods.

[13]  A. Schuurs,et al.  A sol particle agglutination assay for human chorionic gonadotrophin. , 1981, Journal of immunological methods.

[14]  C. Christensen Arrays in biological and chemical analysis. , 2002, Talanta.