An integrated, stacked microlaboratory for biological agent detection with DNA and immunoassays.
An integrated, stacked microlaboratory for performing automated electric-field-driven immunoassays and DNA hybridization assays was developed. The stacked microlaboratory was fabricated by orderly laminating several different functional layers (all 76 x 76 mm(2)) including a patterned polyimide layer with a flip-chip bonded CMOS chip, a pressure sensitive acrylic adhesive (PSA) layer with a fluidic cutout, an optically transparent polymethyl methacrylate (PMMA) film, a PSA layer with a via, a patterned polyimide layer with a flip-chip bonded silicon chip, a PSA layer with a fluidic cutout, and a glass cover plate layer. Versatility of the stacked microlaboratory was demonstrated by various automated assays. Escherichia coli bacteria and Alexa-labeled protein toxin staphylococcal enterotoxin B (SEB) were detected by electric-field-driven immunoassays on a single chip with a specific-to-nonspecific signal ratios of 4.2:1 and 3.0:1, respectively. Furthermore, by integrating the microlaboratory with a module for strand displacement amplification (SDA), the identification of the Shiga-like toxin gene (SLT1) from E. coli was accomplished within 2.5 h starting from a dielectrophoretic concentration of intact E. coli bacteria and finishing with an electric-field-driven DNA hybridization assay, detected by fluorescently labeled DNA reporter probes. The integrated microlaboratory can be potentially used in a wide range of applications including detection of bacteria and biowarfare agents, and genetic identification.
Yang
Joon Mo
JM
Nanogen, Inc., 10398 Pacific Center Court, San Diego, CA 92121, USA. jyang@nanogen.com
Bell
Janice
J
Huang
Ying
Y
Tirado
Marcus
M
Thomas
Donald
D
Forster
Anita H
AH
Haigis
Robert W
RW
Swanson
Paul D
PD
Wallace
R Bruce
RB
Martinsons
Bob
B
Krihak
Michael
M
D001694:Biological Warfare / Q000517:prevention & control; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods; D015342:DNA Probes / Q000737:chemistry*; D004269:DNA, Bacterial / Q000032:analysis* / Q000235:genetics; D004563:Electrochemistry / Q000379:methods; D004574:Electromagnetic Fields; D004586:Electrophoresis / Q000379:methods; D004768:Enterotoxins / Q000032:analysis*; D004867:Equipment Design; D004926:Escherichia coli / Q000145:classification / Q000235:genetics; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D008904:Miniaturization; D021141:Nucleic Acid Amplification Techniques / Q000295:instrumentation* / Q000379:methods; D009693:Nucleic Acid Hybridization; D012666:Semiconductors; D022622:Shiga Toxin 1 / Q000032:analysis* / Q000235:genetics
D015342:DNA Probes; D004269:DNA, Bacterial; D004768:Enterotoxins; D022622:Shiga Toxin 1; C031818:enterotoxin B, staphylococcal