An optical method for rapid screening of blood-borne pathogens

In clinical laboratory work, blood samples are the most common body material used in daily diagnostic tasks. Donated blood needs to be screened for blood-borne diseases before it can be used. This procedure currently takes about twelve hours of laboratory work, and that is acceptable in the case of blood donations. However, the same verification needs to be done in the case of organ transplantations where a 12-hour wait is way too long. Utilizing the currently most sensitive label-free biosensor technology-surface plasmon resonance (SPR)-with a CCD imaging approach allows the construction of a device capable of fast and sensitive detection of blood-borne pathogens. In this paper, a prototype of such an SPR imaging device is presented. Some of the considerations that allow reaching the needed sensitivity and the prototype measurement results are described as well. The completed system was tested with two materials of different optical density, PBS (phosphate buffered saline) and water, at 20degC and 40degC (near-room and near-body temperatures).