AUTHOR=Xia Dongfang , Zhang Yong , Zhang Chunyu , Yao Xiuxiu , Tang Yuhua , Wang Fuchao , Han Xu , Yin Hongzong , Xu Chao , Gao Xueyun 

TITLE=Observation of the protein expression level via naked eye: Pt clusters catalyze non-color molecules into brown-colored molecules in cells

JOURNAL=Frontiers in Chemistry

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2023.1145415

DOI=10.3389/fchem.2023.1145415

ISSN=2296-2646

ABSTRACT=<p><italic>α</italic><sub>v</sub><italic>β</italic><sub>3</sub> is overexpressed in various tumor cells and plays a key role in tumor genesis, invasion, and metastasis. Therefore, it is of great significance to precisely detect the <italic>α</italic><sub>v</sub><italic>β</italic><sub>3</sub> level in cells via a simple method. For this purpose, we have constructed a peptide-coated platinum (Pt) cluster. Due to its bright fluorescence, well-defined Pt atom numbers, and peroxidase-like catalytic activity, this cluster can be used to evaluate <italic>α</italic><sub>v</sub><italic>β</italic><sub>3</sub> levels in cells by fluorescence imaging, inductively coupled plasma mass spectrometry (ICP-MS), and catalytic amplification of visual dyes, respectively. In this report, the expression level of <italic>α</italic><sub>v</sub><italic>β</italic><sub>3</sub> in living cells is well-detected by the naked eye under an ordinary light microscope when the Pt cluster binds to αvβ3 in cells and catalyzes non-color 3,3′-diaminobenzidine (DAB) into brown-colored molecules <italic>in situ</italic>. Moreover, SiHa, HeLa, and 16HBE cell lines with different <italic>α</italic><sub>v</sub><italic>β</italic><sub>3</sub> expression levels can be visually distinguished by the peroxidase-like Pt clusters. This research will provide a reliable method for the simple detection of <italic>α</italic><sub>v</sub><italic>β</italic><sub>3</sub> levels in cells.</p>