Abstract: Objective To explore the feasibility of using Au nanoclusters （AuNCs） to label the tissue engineering scaffold which degradation could be further monitored by noninvasive approach in vivo. Methods Chlorauric acid and bovine serum albumin （BSA） were used to synthesize AuNCs. The nanoclusters were characterized and their cytotoxicity was evaluated. AuNCs were then mixed with poly lactic-co-glycolic acid （PLGA） to fabricate AuNCs/PLGA scaffold. The scaffolds were implanted subcutaneously in nude mice. Fluorescence imaging and CT scanning were performed to detect the scaffolds in vivo. Results Synthesized AuNCs possess fluorescence without cytotoxicity. The AuNCs labeled PLGA scaffolds were detected by fluorescence imaging and CT scanning in vitro. The scaffolds were detected by these two noninvasive methods after being implanted in nude mice. Conclusion AuNCs could be potentially used for labeling polymer scaffold, which degradation could be possibly monitored by non-invasive imaging technology.

Key words: Au nanoclusters, Scaffold, Non-invasive imaging