Analysis of C-reactive protein on amide-linked N-hydroxysuccinimide-dextran arrays with a spectral surface plasmon resonance biosensor for serodiagnosis.
A new label-free array system using amide-linked (AL) NHS-dextran and a spectral SPR biosensor are presented for the high-throughput analysis of C-reactive protein (CRP) in human sera. The AL NHS-dextran layer on the surface of gold arrays was composed of an amide linkage between NHS-modified carboxymethyl-dextran and amine-modified 11-mercaptoundecanoic acid. The topology of the AL NHS-dextran layer was analyzed by atomic force microscopy, and it was found to be superior to the previously used epoxide-linked carboxymethyl-dextran layer in its immobilization of proteins. Specific immunoreactions and a dose-dependent increase of SPR signals were demonstrated on the AL NHS-dextran layer. Then, the label-free array system was successfully applied to the rapid analysis of CRP in 120 human sera. CRP levels in human sera determined by the array-based spectral SPR biosensor showed a good correlation with those determined by the latex-enhanced turbidimetry immunoassay (n = 120, r = 0.945, p < 0.0001). Thus, the array-based spectral SPR biosensor based on the AL NHS-dextran surface is a potential system for rapid and label-free serodiagnosis of human diseases.
Jung
Se-Hui
SH
Department of Molecular and Cellular Biochemistry, Kangwon National University School of Medicine, Chuncheon, Kangwon-Do 200-701, South Korea.
Jung
Jae-Wan
JW
Suh
In-Bum
IB
Yuk
Jong Seol
JS
Kim
Woo-Jin
WJ
Choi
Eui Yul
EY
Kim
Young-Myeong
YM
Ha
Kwon-Soo
KS
D015374:Biosensing Techniques / Q000379:methods*; D002097:C-Reactive Protein / Q000032:analysis*; D003911:Dextrans / Q000737:chemistry*; D006801:Humans; D018625:Microscopy, Atomic Force / Q000379:methods; D040081:Protein Array Analysis / Q000379:methods*; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000379:methods*; D013388:Succinimides / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000379:methods
D003911:Dextrans; D013388:Succinimides; D002097:C-Reactive Protein; C001426:N-hydroxysuccinimide