Two-color multiplexed analysis of eight short tandem repeat loci with an electrophoretic microdevice

Single-channel microfabricated electrophoretic devices equipped with a dual-wavelength laser-induced fluorescence detection system were used for the fast analysis of an eight-loci, two-color multiplex short tandem repeat (STR) system for human identification. Routine analyses of the eight loci (CSF1PO, TPOX, TH01, vWA and D16S539, D7S820, D13S317, D5S818), requiring four-base resolution, were performed in only 2 min. Specific analyses for a microvariant allele (allele 9.3 of the TH01 locus) demanded single-base resolution and was performed in less than 10 min. The high accuracy of the microdevice for real-world STR sample analyses was demonstrated by comparison with conventional slab-gel electrophoresis. Our results show that a fast multiwavelength multichannel electrophoretic microsystem will be capable of routinely processing thousands of complex STR samples per day.