A large field CCD system for quantitative imaging of microarrays

Area of Science:

• Biophotonics
• Microarray technology
• Quantitative imaging

Background:

• Microarray analysis requires high-resolution, quantitative imaging systems.
• Existing systems may lack the dynamic range or field size for comprehensive analysis.

Purpose of the Study:

• To develop and detail a charge-coupled device (CCD) imaging system for microarrays.
• To achieve quantitative, high dynamic range imaging over large fields with high resolution.

Main Methods:

• Utilized an arc lamp for illumination with filters for excitation/emission bands.
• Employed custom detection optics for achromatic imaging (450-750 nm).
• Integrated a cooled 2K x 2K CCD chip for image acquisition under computer control.

Main Results:

• Achieved linearity down to <<1 molecule/microm2 fluorochrome densities.
• Demonstrated illumination intensity uniformity within +/-4% across the field.
• Provided ratio measurements accurate to a few percent over a dynamic range >1000.
• Obtained 10 microm resolution, enabling analysis of >30,000 array elements.

Conclusions:

• The developed CCD imaging system provides accurate, quantitative multicolor images of large microarray fields.
• The system's high dynamic range, resolution, and uniformity minimize the need for computational corrections.
• This technology advances high-throughput microarray analysis and biomarker discovery.