Department of Chemistry, University of Bath, BA2 7AY, UK.
Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, School of Chemistry and Molecular Engineering, Frontiers Center for Materiobiology and Dynamic Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China.
Biomater Sci. 2021 Jun 15;9(12):4433-4439. doi: 10.1039/d0bm01918f.
Alkaline phosphatase (ALP) is an important enzyme-based biomarker present in several bacterial species; however, it is currently undervalued as a strategy to detect pathogenic bacteria. Here, we explore our ALP-responsive colorimetric and fluorescent probe (TCF-ALP) for such applications. TCF-ALP displayed a colorimetric and fluorescence response towards Staphylococcus aureus (S. aureus), with a limit of detection of 3.7 × 106 CFU mL-1 after 24 h incubation. To our surprise, TCF-ALP proved selective towards Staphylococcus bacteria when compared with Enterococcus faecalis (E. faecalis), and Gram-negative P. aeruginosa and E. coli. Selectivity was also seen in clinically relevant S. aureus biofilms. Owing to the high prevalence and surface location of S. aureus in chronic wounds, TCF-ALP was subsequently encapsulated in polyvinyl alcohol (PVA)-based hydrogels as a proof-of-concept "smart" wound dressing. TCF-ALP hydrogels were capable of detecting S. aureus in planktonic and biofilm assays, and displayed a clear colour change from yellow to purple after 24 h incubation using ex vivo porcine skin models. Overall, TCF-ALP is a simple tool that requires no prior knowledge, training, or specialist equipment, and has the potential to overcome issues related to invasive swabbing and tissue biopsy methods. Thus, TCF-ALP could be used as a tool to monitor the early development of infection in a wound and allow for the rapid provision of appropriate treatment for Staphylococcal bacterial infections.
碱性磷酸酶（ALP）是几种细菌中存在的一种重要的基于酶的生物标志物；然而，目前它作为一种检测致病菌的策略还未得到充分重视。在这里，我们探索了我们的 ALP 响应比色和荧光探针（TCF-ALP）在这些应用中的应用。TCF-ALP 对金黄色葡萄球菌（S. aureus）表现出比色和荧光响应，在 24 小时孵育后检测限为 3.7×106 CFU mL-1。令我们惊讶的是，与粪肠球菌（E. faecalis）相比，TCF-ALP 对葡萄球菌具有选择性，与革兰氏阴性的铜绿假单胞菌和大肠杆菌相比也是如此。在临床相关的金黄色葡萄球菌生物膜中也观察到了选择性。由于金黄色葡萄球菌在慢性伤口中的高发生率和表面位置，TCF-ALP 随后被封装在聚乙烯醇（PVA）基水凝胶中，作为一种概念验证的“智能”伤口敷料。TCF-ALP 水凝胶能够在浮游和生物膜测定中检测到金黄色葡萄球菌，并在使用离体猪皮模型孵育 24 小时后从黄色变为紫色，显示出明显的颜色变化。总的来说，TCF-ALP 是一种简单的工具，不需要事先了解、培训或特殊设备，并且有可能克服与侵入性拭子和组织活检方法相关的问题。因此，TCF-ALP 可以用作监测伤口感染早期发展的工具，并允许快速提供适当的金黄色葡萄球菌细菌感染治疗。
