title: Zirconium arsenate-modified silica nanoparticles for specific capture of phosphopeptides and direct analysis by matrix-assisted laser desorption/ionization mass spectrometry.
abstract: In this paper, we report, as far as we are aware, the first use of zirconium arsenate-modified silica nanoparticles (ZrAs-SNPs) for specific capture of phosphopeptides, followed by matrix-assisted laser desorption/ionization mass spectrometric (MALDI MS) analysis. Under the optimized enrichment conditions, the efficiency and specificity of ZrAs-SNPs were evaluated with tryptic digests of four standard proteins (α-casein, β-casein, ovalbumin, and bovine serum albumin) and compared with those of titanium arsenate-modified silica nanoparticles (TiAs-SNPs). The results showed that more selective enrichment of multiply phosphorylated peptides was observed with ZrAs-SNPs than with TiAs-SNPs whereas TiAs-SNPs resulted in slightly better recovery of singly phosphorylated peptides. ZrAs-SNPs were chosen for direct capture of phosphopeptides from diluted human serum of healthy and adenocarcinoma individuals. Our experimental profiling of serum phosphopeptides revealed that the level of phosphorylated fibrinogen peptide A was up-regulated in the serum of adenocarcinoma patients in comparison with healthy adults. This suggests the possibility of using ZrAs-SNPs for discovery of biomarkers of the pathogenesis process of tumors.
authors: Department of Chemistry, Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), Wuhan University, Wuhan 430072, China.
authors: Pei-Xuan
authors: PX
authors: Zhao
authors: Xiao-Feng
authors: XF
authors: Guo
authors: Hong
authors: H
authors: Wang
authors: Chu-Bo
authors: CB
authors: Qi
authors: He-Shun
authors: HS
authors: Xia
authors: Hua-Shan
authors: HS
authors: Zhang
mesh_terms: D000230:Adenocarcinoma / Q000097:blood; D000595:Amino Acid Sequence; D000818:Animals; D001149:Arsenates / Q000737:chemistry*; D002417:Cattle; D006801:Humans; D008969:Molecular Sequence Data; D053758:Nanoparticles / Q000737:chemistry*; D010748:Phosphopeptides / Q000032:analysis / Q000097:blood / Q000302:isolation & purification*; D010750:Phosphoproteins / Q000032:analysis / Q000097:blood / Q000302:isolation & purification; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D001149:Arsenates; D010748:Phosphopeptides; D010750:Phosphoproteins; D015040:Zirconium; C025657:arsenic acid