Patent ID: 7515268

Claim:
An apparatus, comprising: an interrogation platform disposable in association with a plumbing arrangement adapted to transport particles suspended in a fluid, said plumbing arrangement being configured to urge transit of said particles in substantially single-file through a first orifice disposed to provide a first flow path through a substantially opaque member; a radiation source disposed on a first side of said opaque member, said radiation source being arranged to apply primary radiation in a direction along a radiation vector into a zone associated with said first orifice effective to excite a first subset of particles passing through said zone operably to cause an emission of fluorescence from a first particle selected from said first subset, with a first portion of fluorescence from said first particle being directed for transmission in a direction from said first side toward a second side of said substantially opaque member and through said first orifice; and a radiation detector disposed on said second side of said substantially opaque member, said second side being opposite said first side, said radiation detector being operably arranged for reception and detecting of said first portion.