Data_Sheet_1_Assessing the Covalent Attachment and Energy Transfer Capabilities of Upconverting Phosphors With Cofactor Containing Bioactive Enzymes.PDF

Upconverting phosphors (UCPs) convert multiple low energy photons into higher energy emission via the process of photon upconversion and offer an attractive alternative to organic fluorophores for use as luminescent probes. Examples of biosensors utilizing the apparent energy transfer of UCPs and nanophosphors (UCNPs) with biomolecules have started to appear in the literature but very few exploit the covalent anchoring of the biomolecule to the surface of the UCP to improve the sensitivity of the systems. Here, we demonstrate a robust and versatile method for the covalent attachment of biomolecules to the surface of a variety of UCPs and UCNPs in which the UCPs were capped with functionalized silica in order to provide a surface to covalently conjugate biomolecules with surface-accessible cysteines. Variants of BM3Heme, cytochrome C, glucose oxidase, and glutathione reductase were then attached via maleimide-thiol coupling. BM3Heme, glucose oxidase, and glutathione reductase were shown to retain their activity when coupled to the UCPs potentially opening up opportunities for biosensing applications.

上转换磷光体（UCPs）通过光子上转换过程将多个低能光子转换为高能发射，为有机荧光染料的替代品提供了诱人的选择，用作发光探针。文献中开始出现利用上转换磷光体（UCPs）和纳米磷光体（UCNPs）与生物分子的明显能量转移的生物传感器实例，但其中仅有极少数通过将生物分子共价锚定在上转换磷光体表面来提高系统的灵敏度。在此，我们展示了一种稳健且通用的方法，用于将生物分子共价连接到多种上转换磷光体和纳米磷光体表面，其中上转换磷光体被功能化二氧化硅覆盖，以提供共价连接表面可及的半胱氨酸的生物分子的表面。随后，通过马来酰亚胺-硫醇偶联，将BM3Heme、细胞色素C、葡萄糖氧化酶和谷胱甘肽还原酶的变体连接。研究表明，BM3Heme、葡萄糖氧化酶和谷胱甘肽还原酶在与上转换磷光体偶联后仍保持其活性，这可能会为生物传感应用开辟新的机遇。