Abstract: A CMOS buried quad-junction (BQJ) photodetector chip was designed for quantitative analysis in multi-labeling fluorescence detection applications. The chip integrates four-channel charge preamplifiers associated to the multi-output BQJ detector. The chip was tested for noise analysis and evaluation of the amplifiers’ characteristics. It has a sensitivity of 21.2V/lxs at 555nm and a detectivity D* up to 3×1013 cmHz1/2 W−1. A test of the chip for a two-label fluorescence case was performed using a mixture of quantum dots in a priori unknown proportions. Good agreement was obtained between the modeled and measured results. [Copyright &y& Elsevier]