Multifunctional polyethyleneimine for synthesis of core-shell nanostructures and electrochemiluminescent detection of three AMI biomarkers

Abstract

Simplicity and stability of an analytical method are the key to practical applications. In order to achieve such a goal, a molecule with multifunction could be one of the strategies. In this work, the multifunctional characteristics of branched polyethylenemine (bPEI) were employed for verification of this hypothesis. Three types of amines in the bPEI can be used to synthesize core-shell nanostructures (bPEI@Au and SiO 2 @bPEI@Au) in a simple one-pot process within 1 h, and as coreactants with over 500-fold enhancement for electrochemiluminescent (ECL) detection. Based on the remarkable performance of bPEI, a label-free ECL immunosensor and its array with the same assembly strategy were constructed for the simple and rapid determination of three acute myocardial infarction (AMI) biomarkers: cardiac troponin I (cTnI), human-type fatty acid binding protein (hFABP) and copeptin. Both methods exhibited excellent stability and sensitivity with wide linear range and low limits of detection down to fg/mL level by the photomultiplier tube and pg/mL level by the electron-multiplying charge-coupled device.

The line defects in two-dimensional Bi2O2S: enhanced photocurrents in the infrared region

“…In a previous experiment, Jiang and co-workers found that the introduction of rich V O can decrease the band gap of Bi 2 O 2 S from 1.34 to 1.28 eV and, under visible light irradiation, promote the efficiency of the photocatalytic CO 2 reduction process. 44 In a word, the above experimental or theoretical studies indicate that the structural defects in Bi 2 O 2 X materials may play an important role in determining the physical and chemical properties.…”

Electrochemiluminescence of iridium(iii)/ruthenium(ii) complexes with naphthyl tags in solutions and host–guest thin films

“…[1][2][3][4] Owing to its intrinsic advantages such as extremely low background, high sensitivity, excellent spatiotemporal controllability, and a wide dynamic range, ECL has been widely applied in environmental analysis, clinical diagnosis, immunoassays, nucleic acid determination, and other chemo-/biosensors. [5][6][7][8][9][10][11][12][13] Tris(2,2′-bipyridyl)ruthenium(II) (Ru(bpy) 3 2+ ) and its derivatives are the most widely used ECL luminophores because of their excellent ECL performance in aqueous solutions and diverse bio-conjugation sites. While most ruthenium(II) complexes produce ECL that is mainly in the orange-red range of the visible spectrum, wavelengthresolved multiplexed ECL assays are thus limited by the use of ruthenium(II) complexes as signal reporters.…”