A Simplified Visible/Near-Infrared Spectrophotometric Approach to Blood Typing for Automated Transfusion Safety

Abstract

A new technique has recently been introduced for objectively quantifying the agglutination of red blood cells in a blood typing procedure using ultraviolet/visible spectroscopy. The technique involves analyzing the spectra of red blood cell suspensions in saline between the 665 nm and 1000 nm range, where the relative slope between a control and antibody treated sample are entered into a simple algorithm to form a so called agglutination index (A.I.).

The proposal of this research is to simplify the detection method by replacing the spectral imaging of the diode array spectrophotometer with a discrete series of LED and photodiode pairs within the wavelength range of interest, in the forward scattering direction. The scattering theory involved in this phenomenon is investigated, and a simplified experimental sensor is designed and evaluated. The resulting experimentation shows a significant recreation of the spectrophotometer results by the simplified design with a promising potential for improvement. Optoelectronic design considerations are discussed for maximizing the sensitivity of this technique for use in a cost effective, automated device for transfusion safety.