Fabrication Of Middle/low Density Biochip Micromarrayer And Research For Hydrophilic/hydrophobic Biochip Substrate

Micromarrays biochips is a exact, quick and high throughout detection of cell, protein, DNA and other bio-constituents by observe hybridize signs of each sample, The sample labelled fluorescence materials hybridize to probe which immobilize on solid substrate by microfabricaton technology. Micromarrays biochips integrate physics, chemistry, microelectronics, mechanics and life science and other correlative fields. It is a high science and technology problem both with importance academic value and bright industrialization foreground. As research for more than 10 years, middle/low-density spot is a suitable application for clinic detection. As a result, the key technology of micromarrays biochips——dispenser, turn to middle/low-density spotting research. Focus on the weaknesses of the fabricate middle/low-density spotting technologies at present, the main work and results are summarized as follows:1. Proposed a new type, practicably micromarrays biochip fabrication technology——integrate middle/low-density dispenser spotting by surface tension driving. According to requirement and working principle, the dispenser contains reservoirs, channel and hydrophilic membrane. CO₂ laser was used to ablate the 75×30mm² dispenser which contains 3×8 ellipse reservoirs. Each reservoir is as large as 5×3mm², deep in 2mm. The center distance of line and row between reservoirs are 4mm, 8mm respectively. The channel with the average diameter of 0.5mm, length of 1mm has a hydrophilic membrane which diameter of 1.97mm on the bottom.2. Assembled micromarrayer system and debugging by reference commercial micromarrayer. The micromarrayer can spot 2×6 times at a time, with a high efficiency of 170 spots/s and low efficiency of 17 spots/s while the dispenser lifts a high of 5mm. The meaning of operation parameter and notes of operation are analysis.3. Spotting using self-fabrication dispenser. The spot diameter change with the substrate change at the same spotting parameter, the CV of the diameter of spots is below 0.3%. FITC as a spotting sample for research, the intensity of fluorescence of spots are the same with the same spot volume; In a single spot, fluorescence intensity is flat and maximum inside, while attenuate to zero at the edge. The"coffee ring"effect which occurs using conventional micromarrayer spotting was disappeared. Fluorescence intensity is flat and maximum inside meaning that the sample was distribute homogeneous inside, this can improve spot quality out of question. Influence of spot quality which was discussed from spotting principle and results as follows: dispenser and substrate, contact time and interval time during spotting, circumstance and physical/chemical character of sample.4. General character of superdydrophobic was studied. A micopillar array PDMS surface which the biggest of WCA can reach to about 151°at the size, distance, height of the micropillar of 14μm, 6μm, 14μm respectively was prepared by ICP etching model. Several substrates with hydrophilic/hydrophobic pattern were fabricated and doing some primal research of effect of applied this substrate to biochips. It's indicates that substrates with hydrophilic/hydrophobic pattern as a biochip substrate have many merits: homogeneous spot size, uniform spot topography, high detection sensitivity. In a word, this substrate can improve spot quality of biochip.