title: Designed synthesis of aptamer-immobilized magnetic mesoporous silica/Au nanocomposites for highly selective enrichment and detection of insulin.
abstract: We designed and synthesized aptamer-immobilized magnetic mesoporous silica/Au nanocomposites (MMANs) for highly selective detection of unlabeled insulin in complex biological media using MALDI-TOF MS. The aptamer was easily anchored onto the gold nanoparticles in the mesochannels of MMANs with high capacity for highly efficient and specific enrichment of insulin. With the benefit from the size-exclusion effect of the mesoporous silica shell with a narrow pore size distribution (∼2.9 nm), insulin could be selectively detected despite interference from seven untargeted proteins with different size dimensions. This method exhibited an excellent response for insulin in the range 2-1000 ng mL(-1). Moreover, good recoveries in the detection of insulin in 20-fold diluted human serum were achieved. We anticipate that this novel method could be extended to other biomarkers of interest and potentially applied in disease diagnostics.
authors: Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, 220 Handan Road, Shanghai 200433, China.
authors: Ya
authors: Y
authors: Xiong
authors: Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, 220 Handan Road, Shanghai 200433, China.
authors: Chunhui
authors: C
authors: Deng
authors: Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, 220 Handan Road, Shanghai 200433, China.
authors: Xiangmin
authors: X
authors: Zhang
authors: Department of Chemistry and Institutes of Biomedical Sciences, Fudan University, 220 Handan Road, Shanghai 200433, China.
authors: Pengyuan
authors: P
authors: Yang
mesh_terms: D052158:Aptamers, Peptide / Q000138:chemical synthesis*; D006046:Gold / Q000737:chemistry*; D006801:Humans; D007328:Insulin / Q000097:blood*; D060328:Magnetic Phenomena; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D016062:Porosity; D012015:Reference Standards; D012822:Silicon Dioxide / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013696:Temperature
chemical_list: D052158:Aptamers, Peptide; D007328:Insulin; D006046:Gold; D012822:Silicon Dioxide
keywords: MALDI-TOF mass spectrometry; aptamer; insulin; magnetic mesoporous silica/Au nanocomposites; size-exclusion effect