posted on 2024-02-05, 12:33authored byZejun Jiang, Kui Luo, Guangwei Yang, Yang Li, Ling Li, Guocong Wang, Tao Qin, Jianping Li
Cancer-related extracellular vesicles
(EVs) are considered important
biomarkers for cancer diagnosis because they can convey a large amount
of information about tumor cells. In order to detect cancer-related
EVs efficiently, an electrochemiluminescence (ECL) sensor for the
specific identification and highly sensitive detection of EVs in the
plasma of cancer patients was constructed based on dual recognitions
by glycosyl-imprinted polymer (GIP) and aptamer. The characteristic
glycosyl Neu5Ac-α-(2,6)-Gal-β-(1–4)-GlcNAc trisaccharide
on the surface of EVs was used as a template molecule and 3-aminophenylboronic
acid as a functional monomer to form a glycosyl-imprinted polymer
by electropolymerization. After glycosyl elution, the imprinted film
specifically recognized and adsorbed the EVs in the sample, and then
the CD63 aptamer–bipyridine ruthenium (Aptamer–Ru(bpy))
was added to combine with the CD63 glycoprotein on the extracellular
vesicle’s surface, thus providing secondary recognition of
the EVs. Finally, the EVs were quantitatively detected according to
the ECL signal produced by the labeled bipyridine ruthenium. When
more EVs were captured by the imprinted film, more probes were obtained
after incubation, and the ECL signal was stronger. Under the optimized
conditions, the ECL signal showed a good linear relationship with
the concentration of EVs in the range of 9.5 × 102 to 9.5 × 107 particles/mL, and the limit of detection
was 641 particles/mL. The GIP sensor can discriminate between the
EV contents of cancer patients and healthy controls with high accuracy.
Because of its affordability, high sensitivity, and ease of use, it
is anticipated to be employed for cancer early detection and diagnosis.