Strong Electrochemiluminescence from MOF Accelerator Enriched Quantum Dots for Enhanced Sensing of Trace cTnI

Abstract

The development of a sensitive and practical electrochemiluminescence (ECL) bioassay relies on the use of ECL signal tags whose signal intensity is high and stable. In this work, strong ECL emission was achieved from metal organic framework (MOF) accelerator enriched quantum dots (CdTe), which were applied as an efficient ECL signal tag for trace biomarker detection. It is particularly noteworthy that a novel mechanism to drastically enhance the ECL intensity of CdTe is established because isoreticular metal organic framework-3 (IRMOF-3) with 2-amino terephthalic acid (2-NH-BDC) as the organic ligand not only allows for loading a large amount of CdTe via the encapsulating effect and internal/external decoration but also functions as a novel coreactant accelerator for promoting the conversion of coreactant SO into the sulfate radical anion (SO), further boosting the ECL emission of CdTe. On the basis of the simple sandwich immunoreaction approach, cardiac troponin-I antigen (cTnI), a kind of biomarker related with myocardial infarction, was chosen as a detection model using an IRMOF-3-enriched CdTe labeled antibody as the signal probe. This immunosensor demonstrated desirable assay performance for cTnI with a wide response range from 1.1 fg mL to 11 ng mL and a very low detection limit (0.46 fg mL). This suggested that the IRMOF-3-enriched CdTe nanocomposite strategy can integrate the coreactant accelerator and luminophore to significantly enhance the ECL intensity and stability, providing a direction for promising ECL tag preparation with broad applications.

Preparation of Highly Stable and Photoluminescent Cadmium‐Free InP/GaP/ZnS Core/Shell Quantum Dots and Application to Quantitative Immunoassay

“…To date, several kinds of aqueous QD‐based biological detection techniques have been developed . Recently, our group has obtained aqueous high‐quality CdSe core/shell QDs via amphiphilic polymer (polymaleic acid n ‐hexadecanol ester, PMAH) coating technique and also adapted CdSe QD‐based lateral flow immunoassay (LFIA) for qualitative and quantitative detection of human chorionic gonadotropin (HCG), procalcitonin (PCT), influenza A virus, and C‐reactive protein .…”

In-situ Polymerization of N-(3-aminobenzyl)-N, N-dimethyl-N-dodecyl Ammonium Bromide on Glassy Carbon Electrode for Estradiol Detection

“…It has been widely used in biological analysis, organic reaction mechanism research and other fields. The modified electrode has the advantages of increased stability, increased sensitivity, enhanced signal, and specificity [9][10][11][12]. More importantly, the modified electrode-based ECL system is not limited by the dispersion of the material in the medium [13,14].…”

Bifunctional Nanoprobes Used for Label‐Free Determination of Cardiac Troponin I

“…The ECL intensity and cTnI concentration showed a good linear relationship after taking the common logarithm, and the detection limit was determined to be 15.4 pg mL À 1 . Considering the short time from incubation with the targets to the start of measurement due to the pre-functionalized nanoprobes, the present sensing platform combined with the antibody functionalized nanoprobes hold great promise for the practical application compared with that obtained using the complex fabrication of electrode [9,[17][18][19][20][21][22][23][24][25][26][27][28][29] (Table S1 summarized the parameters used in the literature for the cTnI determination, preparation time was calculated according to the fabrication of functionalized electrode surface. Since some reports used the complex assembly process, the analyses were time-consuming).…”