An Experimental Study Of The Laser Confocal Scanning System Equipped With Holographic Filters For Genechip Detection

Genechip technology as a very useful means of biotechnology has been applied to many research areas such as gene discovery, disease diagnosis and pharmacogenomics etc., but commercially available gene-chip detection instruments are too expensive to be accepted by common labs. Some gene-chips such as low-density arrays do not require very high accuracy and sensitivity, which can be detected by simpler confocal systems.In this paper, a laser confocal scanning system with holographic notch filters used for simple gene-chip detection is presented. The volume holographic notch filters were fabricated in our lab to substitute for the expensive narrow-band interference filter and the dichroic filter in the conventional confocal detection system.At first, the genechip technology was introduced.Then, the characteristic of the holographic filters and their functions in the system were analyzed. The confocal system was designed and constructed, and its sensitivity was determined by static measurement.Next, the gengchips were scanned by using a digital controlled X-Y platform and the fluorescence induced by laser was detected, and the computer reconstructed two-dimensional images of fluorescence intensity.Last, the detection results and the methods of improving the performance of the system were discussed.The experimental results indicate that the confocal system can be used for the detection of some low-density genechips that do not require very high accuracy and sensitivity. It's possible to develop a cheap and practical genechip scanner with further improvement of the system. That will promote the application of genechip technology.