Abstract:
An instrument for quantitative analysis includes two shutters (18, 34), one of which (18) prevents light from being introduced into a black box (10) housing a cell holder (26) from the outside through a port in which a cell (14) may be placed in and taken out the black box, and the other of which (38) prevents light from impinging on a photomultiplier tube (34) which is in communication with the black box. The shutters are controlled by means of a control unit so that one of the shutters opens when the other closes. The instrument also includes detectors (66a, 66b) which detect whether or not the cell holder (26) and the cell (14) are disposed at predetermined positions, respectively. The detectors output signals to the control unit. The control unit controls an automatic pipetting device (25) to restrict a sample from being introduced into the cell when both the cell holder and the cell are not disposed at the predetermined position.
Abstract:
A multi-chronal fluorescence imaging technique for spatial differentiation and correlation of a plurality of separate sample components tagged with site specific dyes is described. The dyes have decay times that are widely separated and vary by approximately a factor of ten from one dye to the next. These are added to the sample and are excited with a short pulse of ultraviolet light. Between the sample and a detector is placed an adjustable shutter or gate which is opened and closed at predetermined intervals so that the detector can see the approximate maximum intensity output of each dye in a shown ordered sequence without significant interference from the other dyes.
Abstract:
A multi-chronal fluorescence imaging technique for spatial differentiation and correlation of a plurality of separate sample components tagged with site specific dyes is described. The dyes have decay times that are widely separated and vary by approximately a factor of ten from one dye to the next. These are added to the sample and are excited with a short pulse of ultraviolet light. Between the sample and a detector is placed an adjustable shutter or gate which is opened and closed at predetermined intervals so that the detector can see the approximate maximum intensity output of each dye in a shown ordered sequence without significant interference from the other dyes.
Abstract:
A sample holder and shutter assembly (20) for photometers in which a stationary sample chamber body (40) is mounted in close proximity to a photosensitive device (18). A light path is provided from the sample chamber (53) to the photosensitive device (18) and shutter means is provided for selectively interrupting and opening the light path between the photosensitive device (18) and the sample chamber (53) without moving the sample chamber. Heat exchange means including a heat pump (63) and a heat reservoir (68) are provided for maintaining a desired temperature in the sample chamber (53). The sample chamber body (40) is thermally connected to said heat pump (63) and is preferably thermally isolated from the means mounting it. In one embodiment, the heat pump (63) and heat reservoir (68) are flexibly connected.