Patent ID: 7110585

Claim:
Apparatus for detecting particles on a substrate, the apparatus comprising in combination: a substrate holder; a processor; a memory in communication with the processor; an imaging module in communication with the processor, the imaging module having a fixed position relative to the substrate holder; an illumination module for illuminating the substrate; and a set of instructions stored in the memory and executable by the processor to receive input from the imaging module and to provide an output indicating whether particles are detected, wherein the memory includes program logic executable by the processor to: (i) cause the imaging module to acquire multiple images of one or more spots on a substrate in the substrate holder; and (ii) determine, based on the multiple images of the one or more spots, the presence of metallic nanoparticle complexes in one of the one or more spots as an indication of presence of one or more target analytes, wherein the multiple images are obtained using different amounts of exposure time, and wherein the one or more spots includes at least (i) a first spot arranged as a first test spot containing a test sample, and (ii) a second spot arranged as a control spot or a second test spot.