摘要 |
<p>A method for determining the level of an analyte in a sample of whole blood uses the technique of internal reflection spectroscopy and an apparatus suitable for the technique. The method is of particular use to detect the attenuation of the totally reflected light by absorption of the evanescent wave, e.g., by haemoglobins. In the apparatus (1) incident light is directed via a light guide (7) to the reflection element (3) and the attenuated totally reflected light is directed out of the element to a photodetector (12) by a light guide (11). In the whole blood in the cuvette (18) the cells are removed from the interface (8) by gravity to leave blood cell free plasma (4) adjacent the interface (8). Thus analytes present in the plasma can be detected. The extent of haemolysis can be estimated.</p> |