Effect of the immobilisation of DNA aptamers on the detection of thrombin by means of surface plasmon resonance.
We report a multichannel surface plasmon resonance (SPR) sensor for detection of thrombin via DNA aptamers immobilized on the SPR sensor surface. A detailed investigation of the effect of the immobilisation method on the interaction between thrombin and DNA aptamers is presented. Three basic approaches to the immobilisation of aptamers on the surface of the SPR sensor are examined: (i) immobilisation based on chemisorption of aptamers modified with SH groups, (ii) immobilisation of biotin-tagged aptamers via previously immobilized avidin, neutravidin or streptavidin molecular linkers, and (iii) immobilisation employing dendrimers as a support layer for subsequent immobilisation of aptamers. A level of nonspecific binding of thrombin to immobilized human serum albumin (HSA) for each of the immobilisation methods is determined. Immobilisation of aptamers by means of the streptavidin-biotin system yields the best results both in terms of sensor specificity and sensitivity.
Ostatná
Veronika
V
Department of Nuclear Physics and Biophysics, Comenius University, Mlynská dolina F1, 842 48, Bratislava, Slovak Republic.
Vaisocherová
Hana
H
Homola
Jirí
J
Hianik
Tibor
T
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001360:Avidin / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D001710:Biotin / Q000737:chemistry; D050091:Dendrimers / Q000737:chemistry; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012709:Serum Albumin / Q000737:chemistry; D019809:Streptavidin / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000379:methods*; D013917:Thrombin / Q000032:analysis*
D052157:Aptamers, Nucleotide; D050091:Dendrimers; D012709:Serum Albumin; D013438:Sulfhydryl Compounds; C093483:neutravidin; D001360:Avidin; D001710:Biotin; D019809:Streptavidin; D013917:Thrombin