基于鲁米诺@AuPt/ZIF-67 和 MnO@CNTs 的双猝灭 ECL 免疫传感器用于超灵敏检测视黄醇结合蛋白 4

A dual-quenched ECL immunosensor for ultrasensitive detection of retinol binding protein 4 based on luminol@AuPt/ZIF-67 and MnO@CNTs.

机构信息

Medical Examination Centre, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China.

Department of Endocrinology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, China.

出版信息

J Nanobiotechnology. 2021 Sep 8;19(1):272. doi: 10.1186/s12951-021-01020-1.

BACKGROUND

Retinol binding protein 4 (RBP4) has been regarded as an important serological biomarker for type 2 diabetes mellitus (T2DM). Hence, the construction of a highly sensitive detection method for RBP4 is the key to early prevention and multidisciplinary intervention of T2DM. In this work, a dual-quenched electrochemiluminescence (ECL) immunosensor has been fabricated for ultrasensitive detection of RBP4 by combining zeolitic imidazolate framework-67/AuPt-supported luminol (luminol@AuPt/ZIF-67) with MnO nanosheets-grown on carbon nanotubes (MnO@CNTs).

RESULTS

AuPt/ZIF-67 hybrids with high-efficiency peroxidase-like activity could provide multipoint binding sites for luminol and antibodies and significantly boost the amplified initial signal of the ECL immunosensor. Upon glutathione/HO coreactants system, MnO@CNTs composites could quench the initial signal by inhibiting mimic peroxidase activity of luminol@AuPt/ZIF-67. Moreover, the absorption spectrum of the MnO@CNTs composites completely overlaps with the emission spectrum of luminol, which can further reduce initial signal by ECL resonance energy transfer (ECL-RET).

CONCLUSIONS

Benefiting from the above-mentioned properties, the designed immunoassay sensitivity exhibited excellent sensitivity and relative stability for RBP4 detection range from 0.0001 to 100 ng mL with a low detection limit of 43 fg mL. Therefore, our ECL immunosensor provides an alternative assaying strategy for early diagnosis of T2DM.

背景

视黄醇结合蛋白 4（RBP4）已被视为 2 型糖尿病（T2DM）的重要血清生物标志物。因此，构建一种高灵敏度的 RBP4 检测方法是 T2DM 早期预防和多学科干预的关键。在这项工作中，通过将沸石咪唑酯骨架-67/AuPt 负载的鲁米诺（luminol@AuPt/ZIF-67）与负载在碳纳米管上的 MnO 纳米片（MnO@CNTs）相结合，构建了一种用于超灵敏检测 RBP4 的双猝灭电化学发光（ECL）免疫传感器。

结果

具有高效过氧化物酶样活性的 AuPt/ZIF-67 混合物可为鲁米诺和抗体提供多点结合位点，并显著提高 ECL 免疫传感器的初始信号放大。在谷胱甘肽/HO 反应剂体系中，MnO@CNTs 复合材料可以通过抑制 luminol@AuPt/ZIF-67 的模拟过氧化物酶活性来猝灭初始信号。此外，MnO@CNTs 复合材料的吸收光谱与鲁米诺的发射光谱完全重叠，这可以通过电化学共振能量转移（ECL-RET）进一步降低初始信号。