Multipoint parallel excitation and CCD-based imaging system for high-throughput fluorescence detection of biochip micro-arrays

We report the development and the characterization of a multipoint parallel excitation and CCD-based imaging system for high-throughput fluorescence d etection of biochip micro-arrays. A two-dimensional array of (19 x 19) poin ts with uniform intensity distribution, generated by a holographic array ge nerator, was used for parallel excitation of two-dimensional micro-arrays o f fluorescence samples. A CCD-based imaging system was used for high-throug hput parallel detection and quantitative analysis of the fluorescence outpu t. Micro-array samples of cyanine (Cy5) dye dots on silicon wafers and on g lass substrates with varying concentration were used to evaluate the perfor mance of the system. Results of fluorescence intensity measurements with va rying concentration of dye and with different image acquisition time are pr esented. We have demonstrated that this novel approach will, in general. ou tperform the conventional approach in the excitation efficiency, the signal -to-noise ratio, and the throughput. The limitations and the potential impr ovements of the present method are discussed. (C) 2001 Elsevier Science B.V . All rights reserved.