Aptamer and 5-fluorouracil dual-loading Ag2S quantum dots used as a sensitive label-free probe for near-infrared photoluminescence turn-on detection of CA125 antigen.
In this article, Ag2S quantum dots (QDs) were prepared by a facile aqueous synthesis method, using thiourea as a new sulfur precursor. Based on electrostatic interactions, 5-fluorouracil (5-Fu) was combined with the aptamer of CA125 antigen to fabricate aptamer/5-Fu complex. The surface of as-prepared Ag2S QDs was modified with polyethylenimine, followed by combination with the aptamer/5-Fu complex to form Ag2S QDs/aptamer/5-Fu hybrids. During the combination of Ag2S QDs with aptamer/5-Fu complex, near-infrared (NIR) photoluminescence (PL) of QDs (peaked at 850nm) was markedly reduced under excitation at 625nm, attributed to photo-induced electron transfer from QDs to 5-Fu. However, the addition of CA125 induced obvious NIR PL recovery, which was ascribed to the strong binding affinity of CA125 with its aptamer, and the separation of aptamer/5-Fu complex from the surface of QDs. Hence, the Ag2S QDs/aptamer/5-Fu hybrids were developed as a novel NIR PL turn-on probe of CA125. In the concentration range of [CA125] from 0.1 to 106ngmL-1, there were a good linear relationship between NIR PL intensities of Ag2S QDs and Log[CA125], and a low limit of detection of 0.07ngmL-1. Experimental results revealed the highly selective and sensitive NIR PL responses of this probe to CA125, over other potential interferences. In real human body fluids, this probe also exhibited superior analytical performance, together with high detection recoveries.
Collaborative Innovation Center for Marine Biomass Fiber Materials and Textiles, College of Chemistry and Chemical Engineering, Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, Laboratory of Fiber Materials and Modern Textile, The Growing Base for State Key Laboratory, Qingdao University, Qingdao 266071, PR China. Electronic address: jh8381@163.com.
Hui
H
Jin
Collaborative Innovation Center for Marine Biomass Fiber Materials and Textiles, College of Chemistry and Chemical Engineering, Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, Laboratory of Fiber Materials and Modern Textile, The Growing Base for State Key Laboratory, Qingdao University, Qingdao 266071, PR China. Electronic address: guirijun@qdu.edu.cn.
Rijun
R
Gui
Department of Chemistry, College of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
Jun
J
Gong
Department of Chemistry, College of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
Wenxue
W
Huang
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D018394:CA-125 Antigen / Q000032:analysis / Q000097:blood* / Q000652:urine*; D005472:Fluorouracil / Q000737:chemistry*; D005750:Gastric Juice / Q000737:chemistry; D006801:Humans; D007259:Infrared Rays; D057230:Limit of Detection; D008163:Luminescent Measurements / Q000379:methods; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure; D018030:Silver Compounds / Q000737:chemistry
D052157:Aptamers, Nucleotide; D018394:CA-125 Antigen; D018030:Silver Compounds; C013251:silver sulfide; D005472:Fluorouracil
5-Fluorouracil; Ag(2)S quantum dots; Aptamer; CA125 antigen; Near-infrared photoluminescence