Surface plasmon resonance signal enhancement based on erlotinib loaded magnetic nanoparticles for evaluation of its interaction with human lung cancer cells

Surface plasmon resonance (SPR) sensor provides a very useful tool based on its label-free, real-time monitoring and low price properties. However, measurement of small molecules and extremely diluted analytes is difficult and therefore, signal enhancement is required. In the present study, signal enhancement of erlotinib conjugated magnetic nanoparticles (erlotinib-MNPs) compared to erlotinib was evaluated via their interaction with over-expressed epidermal growth factor receptor on human lung cancer cells (A549 cell line) surface using SPR sensor at three temperature levels. The attained results showed an average signal amplification of about 2.5-fold for MNP-erlotinib interaction with A549 cells compared to erlotinib interaction with those cells. Overall, this signal enhancement method could be used for measurement of small molecules and cancer cell detection via interaction of their overexpressed receptor and various ligands.