College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
Mikrochim Acta. 2019 Nov 25;186(12):841. doi: 10.1007/s00604-019-3895-6.
A luminescent microRNA nanoprobe based on the target-triggered Ir(III)-solvent complex release has been fabricated. The complex is initially embedded into mesoporous silica nanoparticles (MSNs), and then is capped by single-stranded (ss) DNA. In the presence of the target microRNA, the ssDNA hybridize with the microRNA forming a rigid DNA/RNA heteroduplexes and leaving the surface of MSN. Thus, the capped Ir(III) solvent complex is released and re-coordinated with histidine (His) to form a new luminescent complex. The luminescence intensity of the nascent complex (with excitation/emission maxima at 340/570 nm) is positively correlated with the concentrations of the target microRNA in the range from 0.05 to 2 nM, and the detection limit of microRNA is estimated as 0.2 pM (S/N = 3). The ability of this nanoprobe to detect microRNA in cell extract further demonstrates its potential in practical application. Graphical abstractSchematic of a luminescent microRNA nanoprobe based on the target-triggered release of an Ir(III)-solvent complex from mesoporous silica nanoparticles.
基于目标触发的铱（III）-溶剂配合物释放的荧光 miRNA 纳米探针已经被制备出来。该配合物最初被嵌入介孔硅纳米粒子（MSNs）中，然后由单链 DNA（ssDNA）封闭。在目标 microRNA 的存在下，ssDNA 与 microRNA 杂交形成刚性 DNA/RNA 杂双链体，并离开 MSN 的表面。因此，被封闭的 Ir（III）溶剂配合物被释放出来，并与组氨酸（His）重新配位形成新的发光配合物。新形成的配合物的发光强度（激发/发射最大值在 340/570nm 处）与目标 microRNA 的浓度在 0.05 至 2nM 的范围内呈正相关，microRNA 的检测限估计为 0.2 pM（S/N=3）。该纳米探针在细胞提取物中检测 microRNA 的能力进一步证明了其在实际应用中的潜力。
