In-vitro and In-vivo Detection of p53 by Fluorescence Lifetime on a Hybrid FITC-Gold Nanosensor

摘要

P53 is a tumor suppressor used as marker for early cancer diagnosis and prognosis. We have studied constructs based on gold nanoparticles (NPs) decorated with specific anti-p53 antibodies and with a fluoresceine derivative, FITC. The interaction of gold surface plasmons with fluorophores bound within few nanometers from the surface, likely induces changes in the fluorophore excited state lifetime. Indeed we found previously that this parameter follows linearly the p53 concentration in solutions (in vitro conditions) up to 200-400 pM, depending on the size of the NP, with a 5 pM uncertainty. We have evaluated here the nanosensor specificity for p53 by testing it in-vitro against bovine serum albumine, beta-lactolglobulin and lysozyme. Moreover, the titration of total cell extracts from p53+/+ or p53-/- cells with the p53antibody decorated gold NPs, indicates that this construct can also be used to detect the presence of p53 in total cell extracts and it will be therefore a valuable tool also for in vivo screening.