Portable DNA-Probe-Array Synthesis System Using Acoustic-Wave Ejector and Atomizer Array

University Of Southern California, Los Angeles CA

Investigators

Abstract

For efficient and convenient DNA sequencing, we propose to develop a portable system for on-demand DNA probe-array synthesis, using two-dimensional MEMS ejector array (to shoot out DNA bases onto a DNA probe chip in any desired sequence) and atomizer array (to scatter away unbound DNA bases from the probe chip). The technical innovations of the proposed system are as follows: (1) the ejector array (unlike a nozzle-based ejector) can eject liquid droplets at any oblique angle, and does not have to be moved to ink a spot with four DNA bases, and (2) the atomizer array atomizes the unbound DNA bases (after a spotting step), and blows off the unwanted bases before moving to another spotting step for DNA synthesis, thus removing the costly step of the washing and drying steps. Also, we will integrate the 2-D ejector array with microchannels, chambers and other microfluidic handling components on a single silicon chip for a small, portable, affordable system. The portable DNA probe synthesis system will allow geneticists to produce any two dimensional array of any DNA sequence on a chip at their sites. One major research objective is to develop a flexible, low cost technology for an efficient genotyping to characterize hundreds of DNA samples for specific mutations for molecular genetic or molecular epidemiologic research. Genotyping is currently very time-consuming (and, therefore, very expensive), and it is timely to develop an efficient and flexible genotyping technique that allows formation of any DNA sequences on a glass chip on demand. The proposed activity will also include (1) research involvement of students from underrepresented groups (through active search of such applicants and more than usual mentoring of the selected students), (2) data and information dissemination through an internet web site that describes detailed information on DNA and protein microprobe-array synthesis on a chip surface through ink-jet printing of DNA bases or peptides, and (3) close collaboration with a research group (at USC's medical school) that specializes on DNA sequencing for genotyping and phenotyping for public health concerns.