Desgin Of In-Situ Synthesis System Of Peptide Nucleic Acids Chips

Gene chip technology is advancing, however, the dilemma between affinity and specificity is still a barrier to the application of gene chip technique on a routine basis. Using peptide nucleic acid (PNA) as the probe of microarray is expected to solve the above problem. This paper is dedicated to design and implement a light-directed in-situ synthesis system of PNA chip, aiming to develop an automated equipment used for the fabrication of middle-high density PNA microarray.This paper focuses on the design and assembling of the in-situ synthesis system for PNA chips. The synthesizer includes virtual mask lithography system, automatic sampling system and a reaction chamber. Thereinto, the exposure software, which developed on the basis of the virtual mask lithography system, by controlling the output images of the digital micromirror device (DMD), can achieve the precisely spatial addressable multi-photodeprotection. Based on a programmable logic controller (PLC), the automatic sampling system, mainly consisting of a pneumatic unit, a device for preactivated and a multi-direction fluid value matrix, is able to carry out the solid-phase PNA synthesis process through a series of basic reagent operations. A PNA chip can be made by sequential several photodeprotection, pre-activation, coupling and capping reaction, those movements were offered by the in-situ synthesizer, which was controlled by the PC software.The synthesizer basically meets the requirements of PNA chip synthesis, which will advance the research related to the fabrication and application of PNA microarray.