PMID- 18777170
OWN - NLM
STAT- MEDLINE
DCOM- 20090126
LR  - 20160512
IS  - 1618-2650 (Electronic)
IS  - 1618-2642 (Linking)
VI  - 393
IP  - 1
DP  - 2009 Jan
TI  - Cholera toxin subunit B detection in microfluidic devices.
PG  - 177-86
LID - 10.1007/s00216-008-2364-6 [doi]
AB  - Fluorescence and electrochemical microfluidic biosensors were developed for the 
      detection of cholera toxin subunit B (CTB) as a model analyte. The microfluidic 
      devices were made from polydimethylsiloxane (PDMS) using soft lithography from 
      silicon templates. The polymer channels were sealed with a glass plate and 
      packaged in a polymethylmethacrylate housing that provided leakproof sealing and 
      a connection to a syringe pump. In the electrochemical format, an interdigitated 
      ultramicroelectrode array (IDUA) was patterned onto the glass slide using 
      photolithography, gold evaporation and lift-off processes. For CTB recognition, 
      CTB-specific antibodies were immobilized onto superparamagnetic beads and 
      ganglioside GM(1) was incorporated into liposomes. The fluorescence dye 
      sulforhodamine B (SRB) and the electroactive compounds potassium hexacyanoferrate 
      (II)/hexacyanoferrate (III) were used as detection markers that were encapsulated 
      inside the liposomes for the fluorescence and electrochemical detection formats, 
      respectively. Initial optimization experiments were carried out by applying the 
      superparamagnetic beads in microtiter plate assays and SRB liposomes before they 
      were transferred to the microfluidic systems. The limits of detection (LoD) of 
      both assay formats for CTB were found to be 6.6 and 1.0 ng mL(-1) for the 
      fluorescence and electrochemical formats, respectively. Changing the detection 
      system was very easy, requiring only the synthesis of different 
      marker-encapsulating liposomes, as well as the exchange of the detection unit. It 
      was found that, in addition to a lower LoD, the electrochemical format assay 
      showed advantages over the fluorescence format in terms of flexibility and 
      reliability of signal recording.
FAU - Bunyakul, Natinan
AU  - Bunyakul N
AD  - Department of Biological and Environmental Engineering, Cornell University, 
      Ithaca, NY, 14853, USA.
FAU - Edwards, Katie A
AU  - Edwards KA
FAU - Promptmas, Chamras
AU  - Promptmas C
FAU - Baeumner, Antje J
AU  - Baeumner AJ
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20080906
PL  - Germany
TA  - Anal Bioanal Chem
JT  - Analytical and bioanalytical chemistry
JID - 101134327
RN  - 0 (Dimethylpolysiloxanes)
RN  - 0 (Ferricyanides)
RN  - 0 (Fluorescent Dyes)
RN  - 0 (Liposomes)
RN  - 0 (Rhodamines)
RN  - 2609-88-3 (lissamine rhodamine B)
RN  - 37758-47-7 (G(M1) Ganglioside)
RN  - 63148-62-9 (baysilon)
RN  - 9012-63-9 (Cholera Toxin)
RN  - U4MAF9C813 (potassium ferricyanide)
SB  - IM
MH  - Biosensing Techniques/*instrumentation/*methods
MH  - Cholera Toxin/*analysis
MH  - Dimethylpolysiloxanes/chemistry
MH  - Electrochemistry
MH  - Ferricyanides/chemistry
MH  - Fluorescence
MH  - Fluorescent Dyes/chemistry
MH  - G(M1) Ganglioside/chemistry
MH  - Liposomes/chemistry
MH  - Microelectrodes
MH  - Microfluidic Analytical Techniques/*instrumentation/*methods
MH  - Rhodamines/chemistry
EDAT- 2008/09/09 09:00
MHDA- 2009/01/27 09:00
CRDT- 2008/09/09 09:00
PHST- 2008/07/16 00:00 [received]
PHST- 2008/08/20 00:00 [accepted]
PHST- 2008/08/18 00:00 [revised]
PHST- 2008/09/09 09:00 [pubmed]
PHST- 2009/01/27 09:00 [medline]
PHST- 2008/09/09 09:00 [entrez]
AID - 10.1007/s00216-008-2364-6 [doi]
PST - ppublish
SO  - Anal Bioanal Chem. 2009 Jan;393(1):177-86. doi: 10.1007/s00216-008-2364-6. Epub 
      2008 Sep 6.