GB1414885A - Compact dynamic multistation photometer utilizing disposable cuvette rotor - Google Patents

Abstract

1414885 Photometric centrifuges UNITED STATES ATOMIC ENERGY COMMISSION 25 Sept 1973 [6 Oct 1972] 44765/73 Heading G1A [Also in Division G2] A photometric analyzer of the centrifuge type has a removable cuvette rotor 5, Fig. 2, which is keyed to a rotor holder 2 by a pin 6. The holder 2 is driven by a motor/brake assembly 36 and has an upstanding retaining rim within which the cuvette rotor sits. The holder has a set of apertures which co-operate with photo-electric devices such as 39 to give timing signals, and a further set of apertures opposite the cuvettes 8 so that light from source 10 can reach the photo-multiplier 15 of the analyzer. The device 39 can be moved along a track, Fig.1 (not shown) to alter the timing, and light source 10 is also adjustable so that it can be positioned over the cuvettes. By turning knob 22 an appropriate filter 17 carried by a plate 16 can be placed beneath the cuvettes, a wheel 33 on the knob shaft operating micro-switches 34 to alter the sensitivity of detector 15. Alternatively a reference cuvette can be used with a feedback system to maintain the detector output constant when the filter is changed. The rotor temperature is measured by a thermistor placed within the pin 6. Cuvette rotor: the rotor comprises two transparent sheets 52, 53, Fig.4, with an opaque sheet 51 between them. The upper sheet has holes 56, 57 through which fluid may be injected into apertures 54, 55 in the central sheet. On rotation the fluid then passes along capillaries 58, 59 to cuvettes 8. Fluid may also be placed in central aperture 60 while the rotor is spinning and it then passes via region 61 along capillary paths formed between plates 51 and 53 until it reaches the cuvettes, Figs. 5 and 6 (not shown).