A Simple Surface Plasmon Resonance Biosensor for Detection and Quantification of Recombinant Human Epidermal Growth Factor (rhEGF) in Escherichia Coli Crude Extract

A reliable detection and quantification assay is important in order to monitor the performance of recombinant human epidermal growth factor (rhEGF) recovery process. Knowing the benefits offered by the surface plasmon resonance (SPR) biosensor, a rhEGF analysis method employing the commercially available BIAcore 3000 equipment was developed by using polyclonal anti-EGF antibody as the capture ligand. The linearity of the assay (determined using the authentic human epidermal growth factor) was found to be in the range of 25 250 ng/mL. The performance of the developed assay was further evaluated in terms of accuracy, precision (intra and inter-assay), detection and quantification limit. The practical applicability of the assay was justified as a high accuracy (within 10% recovery of the target) and precision (less than 3.4% CV) were obtained for Escherichia coli crude extract samples. The assay was highly reproducible given that the intraand inter-assay precision obtained were less than 20 % CV. A considerably high sensitivity was also achieved with 8.0 ng/mL of quantification limit. Key-Words: Quantification assay, recombinant human epidermal growth factor (rhEGF) purification, surface plasmon resonance (SPR), polyclonal anti-EGF antibody, linearity, performance