INRICHTING VOOR HET FOTOMETRISCH ANALYSEREN VAN OPLOSSINGEN.

摘要

1371465 Optical sample holders UNITED STATES ATOMIC ENERGY COMMISSION 16 Nov 1972 [9 Dec 1971] 52878/72 Heading G2J [Also in Division B2] In a photo-metric analyzer for use under conditions of weightlessness a rotor 1 having a ring of sample analysis cuvettes 7 is removably supported on a motor driven housing 2 and held there by a key and a magnet. A light source 6 sends a beam through the cuvettes 7 to a photo-multiplier tube 9 via an adjustable filter selector 11. The housing 2 is braked by a solenoid disk brake assembly 14 and controlled by a pick-up head rotor position indicator comprising photo-diodes. The rotor 1 comprises an opaque plastics disk sandwiched between two transparent plastics disks. A sample is injected through a centrally located part 21 to a sample distribution chamber 20 from where it flows under centrifugal pressure down capillary passageways 22 to overflow collection cavities 24 and to the first arm, but not the second, of passageways 25 which terminate in the cuvettes 7. Sediment collects at the extremities of passageways 22. Air or liquid is then injected to displace the sample free of sediment, into the cuvettes 7. The cuvettes 7 are formed as bores in the opaque disk; the passageways and chambers are machined in its upper surface. Its lower surface has a central entrance port and chamber for reagent and passages similar to passages 22 leading from the chamber direct to the cuvettes 7; in an alternative mode of operation reagents are pre-loaded into the cuvettes and lyophilized, and water on buffers is injected into the spinning rotor through the reagent port. Following analysis, the entire rotor may be discarded and a fresh one inserted. The capillary passageways retain liquids without the assistance of gravity.