one optical chamber of a desired length wherein the adhesive sheet is placed between a first flat sheet and a second flat sheet the first flat sheet comprising at least one inlet hole and at least one outlet hole the vent hole being located at a first end of the optical chamber and the inlet hole being located at a second end of the optical chamber an integrated analytical system employing this cartridge and optionally including a vacuum chuck for holding and registering the cartridge are also disclosed application_number US 55287200 A description referring to fig1 and 3 an optical cuvette cartridge is shown generally at 10 optical cuvette cartridge 10 comprises two substantially flat sheets 12 and 14 these sheets are u201c liquid impermeable u201d which term denotes that they contain and are not affected by the liquid samples which are placed in the cuvette cassette for analysis one and more typically both of these sheets are u201c transparent u201d which term denotes that the sheets are substantially optically transmissive and transmit a substantial amount such as at least about 25 and preferably at least about 50 of light shone upon them at the wavelengths which are relevant to their use as sample cuvettes in spectrophotometric analysis settings sheets 12 and 14 are preferably flexible nonrigid plastic films since many of the spectrophotometric analysis techniques which are carried out using the cuvette cassettes of this invention involve laser stimulation of fluorescence.