Electrostatically controlled fluorometric assay for differently charged biotargets based on the use of silver/copper bimetallic nanoclusters modified with polyethyleneimine and graphene oxide
- 16 Downloads
An electrostatically controlled fluorometric assay is described that is based on the use of silver/copper bimetallic nanoclusters. The nanoclusters were coated with polyethyleneimine (PEI-Ag/CuNCs). At pH 7.4, these particles are positively charged. Their blue fluorescence (with excitation/emission peaks at 341/464 nm) depends on local pH values and temperature. If graphene oxide (which is negatively charged at pH 7.4) is introduced, the fluorescence of the PEI-Ag/CuNCs is quenched. Based on various electrostatic interactions, three kinds of biomacromolecules were detected by fluorometry. These include (negatively charged) heparin, (positively charged) protamine, and (virtually uncharged) trypsin. Heparin is detected by using GO/PEI-Ag/CuNCs, protamine by using GO/heparin/PEI-Ag/CuNCs, and trypsin by using GO/protamine/heparin/PEI-Ag/CuNC. The detection limits and linear ranges are 4.8 nM and 10–450 nM for heparin, 0.09 μg·mL−1 and 0.25–5 μg·mL−1 for protamine, and 0.03 μg·mL−1 and 0.05–1 μg·mL−1 for trypsin. Zeta potentials of the various substances in the system were determined to elucidate the detection mechanism. Comceivably, the method provides a widely applicable approach for electrostatically controlled biomolecular assays.
KeywordsHeparin Protamine Trypsin Electrostatic interactions Multiple targets sensing
The project was supported by State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, China (2019-4).
Compliance with ethical standards
The author(s) declare that they have no competing interests.
- 3.Wu Y, Huang S, Zeng F, Wang J, Yu C, Huang J, Xie H, Wu S (2015) A ratiometric fluorescent system for carboxylesterase dtection with AIE dots as FRET donors. Chem Commun 51:12791–12794Google Scholar
- 4.Fan X, Zhang D, Li H, Sun S, Xu Y (2017) A BSA-squaraine hybrid system for selectively detecting ag+ in absolute PBS and sequential construction of logic functions. Sensors Actuators B Chem 245:290–296Google Scholar
- 5.Jiang G, Wang J, Yang Y, Zhang G, Liu Y, Lin H, Zhang G, Li Y, Fan X (2016) Fluorescent turn-on sensing of bacterial lipopolysaccharide in artificial urine sample with sensitivity down to nanomolar by tetraphenylethylene based aggregation induced emission molecule. Biosens Bioelectron 85:62–67PubMedGoogle Scholar
- 6.Liu J, Liu G, Liu W, Wang Y, Xu M, Wang B (2016) Turn-on fluorometric β-carotene assay based on competitive host-guest interaction between rhodamine 6G and β-carotene with a graphene oxide functionalized with a β-cyclodextrin-modified polyethyleneimine. Microchim Acta 183:1161–1168Google Scholar
- 7.Liu G, Huang X, Zheng S, Li L, Xu D, Xu X, Zhang Y, Lin H (2018) Novel triadimenol detection assay based on fluorescence resonance energy transfer between gold nanoparticles and cadmium telluride quantum dots. Dyes Pigments 149:229–235Google Scholar
- 8.Xie H, Bei F, Hou J, Ai S (2018) A highly sensitive dual-signaling assay via inner filter effect between g-C3N4 and gold nanoparticles for organophosphorus pesticides. Sensors Actuators B Chem 55:2232–2239Google Scholar
- 12.Fang J, Zhang B, Yao Q, Yang Y, Xie J, Yan N (2016) Recent advances in the synthesis and catalytic applications of ligand-protected, atomically precise metal nanoclusters. Coord Chem Rev 322:1–29Google Scholar
- 13.Yue D, Wang M, Deng F, Yin W, Zhao H, Zhao X, Xu Z (2018) Biomarker-targeted fluorescent probes for breast cancer imaging. Chinese Chem Lett 29:648–656Google Scholar
- 16.Wang C, Cheng H, Sun Y, Xu Z, Lin H, Lin Q, Zhang C (2014) Nanoclusters prepared from a silver/gold alloy as a fluorescent probe for selective and sensitive determination of lead(II). Microchim Acta 182:695–701Google Scholar
- 21.Rao H, Ge H, Wang X, Zhang Z, Liu X, Yang Y, Liu Y, Liu W, Zou P, Wang Y (2017) Colorimetric and fluorometric detection of protamine by using a dual-mode probe consisting of carbon quantum dots and gold nanoparticles. Microchim Acta 184:3017–3025Google Scholar
- 22.Kim D, Kim J, Lee TS (2018) Dual-signal detection of trypsin using controlled aggregation of conjugated polymer dots and magnetic nanoparticles. Sensors Actuators B Chem 264:45–51Google Scholar
- 23.Liu Q, Lai Q, Li N, Su X (2018) Copper nanoclusters capped with tannic acid as a fluorescent probe for real-time determination of the activity of pyrophosphatase. Microchim Acta 185:182Google Scholar
- 24.Liu C, Ding Y, Li Q, Lin Y (2017) Photochemical synthesis of glutathione-stabilized silver nanoclusters for fluorometric determination of hydrogen peroxide. Microchim Acta 184:2497–2503Google Scholar
- 29.Xiong H, Wang W, Liang J, Wen W, Zhang X, Wang S (2017) A convenient purification method for metal nanoclusters based on pH-induced aggregation and cyclic regeneration and its applications in fluorescent pH sensors. Sensors Actuators B Chem 239:988–992Google Scholar
- 33.Zu F, Yan F, Bai Z, Xu J, Wang Y, Huang Y, Zhou X (2017) The quenching of the fluorescence of carbon dots: a review on mechanisms and applications. Microchim Acta 184:1899–1914Google Scholar