Igor L. Medintz

High-performance genetic analysis using microfabricated capillary array electrophoresis microplates

This review focuses on some recent advances in realizing microfabricated capillary array electrophoresis (νCAE). In particular, the development of a novel rotary scanning confocal fluorescence detector has facilitated the high‐speed collection of sequencing and genotyping data from radially formatted νCAE devices. The concomitant development of a convenient energy‐transfer cassette labeling chemistry allows sensitive multicolor labeling of any DNA genotyping or sequencing analyte. High‐performance hereditary haemochromatosis and short tandem repeat genotyping assays are demonstrated on these devices along with rapid mitochondrial DNA sequence polymorphism analysis. Progress in supporting technology such as robotic fluid dispensing and batched data analysis is also presented. The ultimate goal is to develop a parallel analysis platform capable of integrated sample preparation and automated electrophoretic analysis with a throughput 10–100 times that of current technology.

High speed single nucleotide polymorphism typing of a hereditary haemochromatosis mutation with capillary array electrophoresis microplates.

A single nucleotide polymorphism (SNP) typing assay is developed and evaluated on a microfabricated capillary array electrophoresis system. Using fluorescently labeled allele‐specific primers, the S65C (193A→T) substitution associated with hereditary haemochromatosis in the HFE gene is genotyped. The covalently labeled polymerase chain reaction (PCR) products are separated on a microfabricated radial capillary array electrophoresis microplate using nondenaturing gel media in under two minutes. Detection is accomplished with a laser‐excited rotary confocal scanner. The Rox‐labeled A‐allele specific amplicon (211 bp) is differentiated from the R110‐labeled T‐allele specific amplicon (201 bp) by both size and color. This study demonstrates the feasibility of using allele‐specific PCR with covalently labeled primers for high speed fluorescent SNP typing on microfabricated radial capillary array electrophoresis microplates.

Microfabricated capillary array electrophoresis DNA analysis systems

Microfabricated laboratory-on-a-chip systems are revolutionizing all aspects of genetic analysis. The development of capillary array electrophoresis (CAE) microchannel plate devices makes possible the performance of 96 or more high-speed separations in parallel on a single wafer-scale device. The fluorescently labeled DNA samples are detected within the microchannels with a novel four-color rotary confocal fluorescence scanner. The capabilities of this system for genotyping are demonstrated through multiplex separations of short tandem repeat and hereditary haemochromatosis allele-specific amplicons. Furthermore, with newly developed folded channel designs that maintain high resolution, these CAE microplate systems are used to perform 96 high-quality DNA sequencing separations in parallel to approximately 500 bases per capillary in less than 30 min. These densely packed microfabricated device technologies will facilitate the even more rapid collection of vast amounts of genetic data in the future.