title: On-chip coupling of free-solution transient ITP and CGE for highly efficient separation of dsDNA with variable sample loading amounts.
abstract: We developed an on-chip DNA analysis method, in which free-solution transient isotachophoresis (FstITP) were coupled with CGE. Using chloride ions in the sample matrix and HEPES in the background electrolyte, respectively, as the leading and terminating ions, dsDNAs were isotachophoretically preconcentrated in free-solution and then separated in sieving polymer. The coupling of FstITP and CGE enabled higher separation efficiency due to higher preconcentration rate in free-solution. The FstITP-CGE analysis offered adjustable signal intensities by varying sample injection time. With the maximum sample loading volume, the LOD of the FstITP-CGE analysis was determined to be 0.24 ng/mL by confocal laser-induced fluorescence detection. The FstITP-CGE method is simple, robust and flexible, thus well suited to the analysis of highly saline DNA samples at different concentration level.
authors.affiliation: Laboratory of Advanced Clinical Chemical Technology, Department of Laboratory Medicine, Guangzhou First Municipal People's Hospital, Affiliated Hospital of Guangzhou Medical College, Guangzhou, P. R. China.
authors.forename: Dayu
authors.initials: D
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Lihui
authors.initials: L
authors.lastname: Wang
authors.forename: Xiaomian
authors.initials: X
authors.lastname: Zhou
mesh_terms: D004247:DNA / Q000302:isolation & purification*; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D018613:Microscopy, Confocal
chemical_list: D004247:DNA