Infrared reflectance from whole blood soaked filter paper and implications in haemoglobinometry

For field use, particularly in a rural environment, where large number of subjects have to be screened, conventional methods for haemoglobin determination such as Sahli's method and the cyanmethaemoglobin method are too cumbersome for practical use. On the other hand, the current methods of whole blood haemoglobin by optical wedge comparison are too unreliable. A new approach based on infra-red reflectance has been proposed here. A novel disposable cell has been devised by means of which a standardised volume of blood from a finger prick can be soaked up without volumetric measurement apparatus. Also the cell prevents dehydration but does not affect infra-red reflectance. Haemoglobin measurements with this new technique can be sufficiently accurate as to meet the needs of field use.