Polyclonal immunosensors

Gonzalez-Martinez, M.A., R. Puchades, A. Maquieira, I. Ferrer, M.P. Marco, and D. Barcelo. (1999). Reversible immunosensor for the automatic determination of atrazine Selection and performance of three polyclonal antisera. Anal. Chim. Acta, 386 201-210. 

Sandakaran et al. reported another SPR immunosensor for TNT. Eor inhibition assay-based detection, BSA-2,4,6 trinitrophenol conjugate was anchored to the sensor surface by physical sorption. The detection was performed using the sensor instrument SPR-670 (Nippon Laser and Electronics, Japan). With polyclonal antibodies against BSA-TNP, a detection limit as low as 0.09 ngmL was achieved in buffer [42]. The sensor exhibited very... 

It is generally considered that Abs bind their Ags with high specificities. However, both polyclonal and monoclonal Abs in general will bind (with varying degrees of affinity) to compounds structurally related to the antigen. In particular, for small molecular weight haptens, polyclonal antibodies may be directed toward the protein used as the carrier as well as to the hapten and chemical structure used to link them. This is an important consideration for certain immunosensor assay formats. 

Immunosensors based on mono- or polyclonal antibodies con.stitute the second best choice with respect to high selectivity. Depending on the amount of effort expended in screening and choosing the desired antibodies from among the millions of different antibody molecules available, the selectivity can be remarkably high. On the other hand, it is also possible to choose antibody mole-... 

Figure 81. Schematic representation of the operation of an immunosensor for delecting the fatly acid binding protein (FABP) A) Analyte binding step B) Introduction of a secondary polyclonal antibody conjugated with glucose oxidase (GOD) ...

Disposable immunosensors for the determination of bacteria based on screen-printed platforms have been also reported in the literature. Afonso et al. (2013) fabricated a screen-printed carbon-based biosensor in combination with magnetic separation for the rapid detection of Salmonella in milk samples. Magnetic beads coated with anti-Salmonella antibodies (MBs-pSAb) and modified AuNPs coated with polyclonal anti-Salmonella antibody were used as the capture phase (preconcentrating step) and electrochemical labels, respectively. The modified magnetic beads were then captured onto the electrode surface by applying a magnetic field below the printed sensors and analysed electrochemically by DPV. 

Antibodies employed in the immunosensor development are of two kinds polyclonal and monoclonal. Polyclonal antibodies are a group of antibodies that are h hly sensitive but less specific since they can recognize different epitopes (the small site on an antigen to... 

Furthermore, research efforts described herein, have resulted in at least a ten-fold improvement in the detection of Clostridium botulinum neurotoxin using a fiberoptic immunosensor. Additionally, the increased sensitivity of the assay by using affinity purified polyclonal antibodies as both the immobilized capture antibodies and the fluorescently labeled antibodies suggests that the investigation into additional assay systems may be worthwhile. 

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