Unmodified and positively charged gold nanoparticles for sensitive colorimetric detection of folate receptor via terminal protection of small molecule-linked ssDNA

摘要: The detection of protein/small molecule interactions plays important roles in drug discovery and protein/metabolite biology. In this work, by coupling the terminal protection small molecule-linked ssDNA strategy with unmodified positively charged gold nanoparticle ((+)AuNP) nanoprobes, we have developed a sensitive simple colorimetric sensor for folate receptor, highly expressed protein many kinds malignant tumors. target receptor binds moieties folate-linked through high affinity protects protein-bound from digestion exonuclease I. protected thus adsorbs electrostatic interactions, leading to red-to-blue color change sensing solution at sub-nanomolar level. Besides, shows selectivity toward against other control proteins. avoids modification/conjugation AuNP nanoprobes involvement any expensive instruments signal transduction detection. Featured these obvious advantages, demonstrated herein can be easily expanded convenient various interactions.