East China University of science and technology has made a new breakthrough in the field of ultra-high fluorescence quantum yield gold nanoclusters

Near infrared luminescent gold nanoclusters are the research hotspot of cancer diagnosis and treatment integrated nano carriers In order to promote the practical application, it is necessary to solve the problem of low quantum yield of gold nanoclusters Recently, the research group of Professor Luan Weiling of East China University of science and technology has made new progress in the preparation of near infrared luminescent gold nanoclusters with high quantum yield The related work was published in the topic of "supramolecular guided synthesis of bright near infrared Au 22 nanoclusters with aggregation induced emission for bioimaging" in particle & particle system characterization (DOI: 10.1002/ppsc.201900314), and was included as the cover paper Gold nanoclusters (auncs) with protein ligands have unique physical and chemical properties, such as near-infrared luminescence band, good biocompatibility and relatively low toxicity They are ideal fluorescence markers in the field of biological imaging and disease diagnosis and treatment However, the fluorescence quantum yield of gold nanoclusters synthesized is generally low In order to solve this problem, Professor Luan Weiling and Professor Gaofeng of the school of pharmacy cooperated to select bovine serum albumin (BSA) as the surface ligand, and explored the role of BSA in the formation of gold clusters in detail It was found that BSA can rapidly capture and reduce Au 3 + ions under appropriate conditions -In 2 hours, the quantum yield of auncs is as high as 23% The formation of supramolecular can effectively inhibit the irregular movement of Au (I) - BSA, and make the obtained auncs have a core-shell structure with high Au (I) - BSA complex tightly surrounding the gold core, which greatly enhances the fluorescence quantum yield (picture source: particle & particle system characterization) in order to further enhance the quantum yield of auncs, the team members realized the aggregation induced luminescence enhancement of protein protected auncs by electrostatic interaction for the first time While enhancing the fluorescence intensity, they also succeeded in removing the unresponsive BSA in the solution After aggregation, auncs are more easily absorbed by cancer cells, and the detection sensitivity of glutathione is increased by three times The first author of the study is Wei Yifei, a postgraduate student, and the corresponding author is Professor Luan Weiling.