In vitro characterization of the LSPR FTP in physiology condition.
(a), Real-time measurement of LSPR shifts at various p53 concentrations. In all cases, the blank PBS was injected into the fluidic channel for the first 5 minutes (before black dashed line). Different concentrations of p53 in PBS were injected into the channel for 15 minutes, followed by additional PBS wash step to observe dissociation of p53 from its antibody (after red dashed line). (b), LSPR shift vs. p53 concentration. Dissociation constant of 5.4 nM is extracted from the fit with Langmuir equation. Three repeated experiments were performed. (c), Specificity test of LSPR FTP sensor. The LSPR FTPs were coated with anti-p53 and anti-TNF-α respectively and both sensors were used to detect p53, p53 in 1% BSA and TNF-α. The significant LSPR shift occurred when coated antibodies paired correctly with their antigens, thus demonstrating high sensor specificity. High specificity retains when the p53 antigens are in high background of BSA.