Fluorescence-detection system promises early HIV warning

17 Jun 2002

An optical blood analyser developed by a small US start-up company could provide early identification of the HIV virus and other infectious diseases.

The Laser Medical Corporation in Burlington, MA has filed an international patent (WO 99/50642) on a system that detects infectious diseases by analysing the fluorescence from the blood.

The apparatus, which is estimated to cost around USD 60,000 to build, is made of an ultraviolet laser, a grating spectrometer and a CCD detector, together with some sophisticated software.

The ultraviolet laser excites the blood sample and the system records the visible fluorescence (between 380 and 600 nanometres). Analysis of the recorded spectrum reveals if the blood is infected.

Currently, HIV is detected through the ELISA test, which searches the blood for antibodies that the body produces after infection. In most cases this happens within six weeks, but it can take as long as six months, according to the AIDs Education and Research Trust.

In contrast, the new fluorescence technique detects the response of organisms in the blood to the initial infection. Joe Canter of the Laser Medical Corporation told Opto & Laser Europe magazine that he believes the system to be a significant improvement. "I can't say exactly how long, but we find that we get a strong fluorescence signal very early on."

The company is focusing on testing for HIV, HCV and hepatitis B and C but it plans to expand to other diseases later. It is currently building five prototypes of the system and is involved in preclinical tests with samples from two different sources. Laser Medical Corporation plans to begin full clinical trials soon.

SH