Label-Free Biochemical Detection Coupled On-Line to Liquid Chromatography

Abstract

The on-line coupling of a label-free optical biosensor to a HPLC system is described by combining the separation power of HPLC with the specificity of the biosensor system. A highly cross-reactive antibody against the pesticide isoproturon was used as model for affinity proteins. The binding strength of the antibody to the utilized pesticides was characterized with the biosensor, first. In the on-line coupling setup, the eluate of the HPLC was mixed continuously with the antibodies. The presence of antigens was detected by a reduction of the antibody binding to the transducer. This reduced binding was quantified by a differentiation of the sensor signal by applying a Savitzky-Golay algorithm. Limits of detection were found to be in the femtomole range without preconcentration, which is comparable to a study using fluorescence-based biochemical detection.

Functionalizable low-fouling coatings for label-free biosensing in complex biological media: advances and applications

“…A variety of strategies have been reported for the immobilization of bioreceptors to sensor coatings [3,15,50,62,63,210]. Most of them can also be applied to the immobilization of b i o r e c e p t o r s t o a n t i f o u l i n g c o a t i n g s ( s e e a l s o "Immobilization of biorecognition elements" section).…”

High-performance electrochemical amperometric sensors for the sensitive determination of phenyl urea herbicides diuron and fenuron

“…Therefore, finding suitable electrode modifiers for the determination of DU is an interesting research [15,16]. Similarly, fenuron (1, 1-dimethyl-3-phenylurea) (FU) is a widely known phenyl urea class herbicide [10,17,18]. It has high polar nature and solubility in water; as a result, its residues have high probability to be present in soil and aquatic environment [19].…”

Flow-Through Multianalyte Chemiluminescent Immunosensing System with Designed Substrate Zone-Resolved Technique for Sequential Detection of Tumor Markers

“…Besides the two dominant modes, a neural network based on one label using cross-reactive antibodies has been proposed for multianalyte immunoassay. , However, this method shows great relative error up to 670% 22 and poor limit of detection . Another method coupled with the separation techniques such as capillary electrophoresis , and liquid chromatography can be used for multianalyte immunoassay. Obviously this strategy makes the detection system more complicated and often encounters the adsorption of immunoreagents on the inner wall of the capillary and chromatographic column.…”