Homemade ultra-flat gold chip dedicated for analysis of grafting antibodies by both SPRi and AFM
Résumé
In this work, we present an experimental method to assess the density of immobilized antibody (Ab) on flat gold terraces using atomic force microscopy (AFM) and surface plasmon resonance imaging (SPRi). The gold terraces were prepared on glass substrates by e-beam evaporation with special parameters developed recently. The monitoring of Ab immobilization was performed using surface plasmon resonance apparatus (SPRi-Plex II from Horiba), which provides kinetics behavior of the grafting and quantitative estimation of the surface coverage of immobilized protein. Interestingly, the atomically flat gold terraces provide suitable imaging of the biochip surface by using AFM (Nanoscope III from Veeco,Santa Barbara,CA, USA). Hence, an accurate observation of the distribution quality was obtained leading to an easy counting of antibodies