Specific and Quantitative Detection of Albumin in Biological Fluids by Tetrazolate-Functionalized Water-Soluble AIEgens Academic Article uri icon

abstract

  • The analysis of albumin has clinical significance in diagnostic tests and obvious value to research studies on the albumin-mediated drug delivery and therapeutics. The present immunoassay, instrumental techniques, and colorimetric methods for albumin detection are either expensive, troublesome, or insensitive. Herein, a class of water-soluble tetrazolate-functionalized derivatives with aggregation-induced emission (AIE) characteristics is introduced as novel fluorescent probes for albumin detection. They can be selectively lighted up by site-specific binding with albumin. The resulting albumin fluorescent assay exhibits a low detection limit (0.21 nM), high robustness in aqueous buffer (pH = 6-9), and a broad tunable linear dynamic range (0.02-3000 mg/L) for quantification. The tetrazolate functionality endows the probes with a superior water solubility (>0.01 M) and a high binding affinity to albumin (KD = 0.25 μM). To explore the detection mechanism, three unique polar binding sites on albumin are computationally identified, where the multivalent tetrazolate-lysine interactions contribute to the tight binding and restriction of the molecular motion of the AIE probes. The key role of lysine residues is verified by the detection of poly-l-lysine. Moreover, we applied the fluorogenic method to quantify urinary albumin in clinical samples and found it a feasible and practical strategy for albumin analysis in complex biological fluids.

authors

  • Tu, Yujie
  • Yu, Yeqing
  • Zhou, Zhibiao
  • Xie, Sheng
  • Yao, Bicheng
  • Guan, Shujuan
  • Situ, Bo
  • Liu, Yong
  • Kwok, Ryan TK
  • Lam, Jacky WY
  • Chen, Sijie
  • Huang, Xuhui
  • Zeng, Zebing
  • Tang, Ben Zhong

publication date

  • 2019