分析测试学报2022，Vol.41Issue(4)：625-631,7.DOI:10.19969/j.fxcsxb.21121901
单颗粒计数策略定量检测癌胚抗原
Quantification of Carcinoembryonic Antigen by Single Particle Inductively Coupled Plasma Mass Spectrometry
摘要
Abstract
Cancer ranks as the leading threat to life expectancy all over the world,based on the latest estimations. Timely diagnosis and treatment of malignancies are still essential procedures to control the growing burden of cancer incidence and mortality.Single particle inductively coupled plasma mass spectrometry(spICP-MS)is a detection method for single par?ticles in time-resolved mode.Inheriting the advantages of ICP-MS,spICP-MS ensures the single-particle counting with high sensitivity and high element resolutions.For immunoassays by this mode,there are breakthroughs not only in improv?ing the detection limits of heterogeneous immunoassay but also in achieving multiplex homogeneous immunoassays with a simpler procedure. In this work, a single particle counting strategy was achieved by spICP-MS for sensitive carcinoem?bryonic antigen(CEA)evaluation.Gold nanoparticles(AuNPs)with a diameter of 50 nm were synthesized by one-step so?dium citrate reduction,which were further applied to CEA-specific capturing. Anti-CEA antibody labeled AuNPs were syn?thesized by electrostatic adsorption between disulfide bonds exposed on the anti-CEA antibodies and the surface of AuNPs . The strategy was based on sandwich immunoassay where anti-CEA antibody labeled magnetic beads(MBs)were applied to capture CEA and antibody labeled AuNPs.After separation by a magnet,MBs were enriched at the bottom of the centrifu?gal tube,while the remaining AuNPs in the supernatant were counted by spICP-MS.The more CEA occurred in the sam?ple,the more AuNPs probes were captured on the surface of MBs,and the fewer numbers of detectable remaining AuNPs were found in the supernatant.The proposed method was more direct and facile without washing steps,compared with the traditional MBs strategy.The experimental conditions were optimized,including magnetic beads volume applied in immu?noassay and dilution ratio of the sample in spICP-MS.Under the optimal conditions,spICP-MS could accurately deter?mine the change of AuNPs numbers in the process of CEA immunoassay,with an efficiency of 2. 1％.The proposed meth?od provided a three-orders-of-magnitude linear range(0. 05-20 ng/mL,r2=0. 997)with a limit of detection(LOD)as low as 0. 017 ng/mL for CEA quantification.The method was also successfully utilized in serum sample analysis with good selectiv?ity,exhibiting a great potential in cancer diagnosis .关键词
单颗粒ICP-MS/AuNPs/磁性纳米颗粒/CEA检测Key words
single particle ICP-MS/AuNPs/magnetic beads/CEA evaluation分类
化学化工引用本文复制引用
黄自立,胡悦莉,刘静,吴仪,赵劲一,刘睿,吕弋..单颗粒计数策略定量检测癌胚抗原[J].分析测试学报,2022,41(4):625-631,7.基金项目
The National Natural Science Foundation of China(22074098,22074096) （22074098,22074096）
