螢光金奈米團簇近期快速發展且廣泛運用於生物醫學領域,做為生醫影像探針以提升其對比度,以螢光金奈米團簇作為主軸研究在奈米生醫、分子影像領域強調其專一性及單一官能化,而大部分螢光金奈米團簇合成後僅具有螢光成像之功能,在靶向應用上需要考量配體官能基及生物接枝之技術,其步驟繁雜且易造成產量降低,為現今須突破之挑戰。本研究合成中加入穀胱甘肽與四氯金酸形成橘紅色螢光金奈米團簇(Au@GSH),利用金-硫鍵結特性改變製程,於合成時加入其他硫醇基生物分子,硫醇基分子與穀胱甘肽競爭金團簇表面配體位置形成披覆一個、二個及三個硫醇基分子,可以利用膠體電泳分析進行分離,達到表面功能化披覆數量可調控性,隨後以不同分子量硫醇基之聚乙二醇驗證披覆金團簇表面單一聚乙二醇化,其次,以具有功能化之聚乙二醇(生物素及葉酸)披覆於金團簇表面,再運用鍊抗生物素蛋白(Streptavidin)與生物素特異性驗證,以及,運用細表面帶有大量葉酸受體之乳癌細胞做為葉酸驗證,最後以穿膜胜肽-精氨酸修飾金團簇後做為細胞嗜入試驗,本研究為改善一般金團簇表面設計開發製程繁複且耗時,發展在奈米團簇合成過程亦可完成表面技術開發,達到提升效能及統一製程,為快速、簡易且高專一性之整合系統。
Fluorescent nanoprobe are rapidly gaining popularity as the most commonly used contrast for imaging in the field of biomedical technology. In this study, we prepared fluorescent, functional thiolate-stabilized gold nanoclusters through one-pot synthesis and then employed them as probes for bioapplication. The Au-thiol bond is a strong interaction for synthesize nanoclusters, so we use this character to replace a part of surface ligand as bio-targeting. Conjugates of nanoclusters with one, two, and three poly(ethylene glycol) (PEG) per nanocluster could be separate using gel electrophoresis. In addition, we use electrostatic interaction to combine cell-penetrating peptides including cysteine with nanoclusters, then co-culture with cell to observe the fluorescent intensity compare favourably with cell-penetrating peptides without cysteine. This is a novel and facile method that nanoclusters surface could functionalize by any target ligand with thiolate group.