Highly specific phosphopeptide enrichment by titanium(IV) cross-linked chitosan composite.
Natural chitosan was applied as supporting material for Ti(IV) based immobilized metal ion affinity chromatographic (IMAC) material (Ti-CTS). Compared with other polymer based IMAC, Ti-CTS can save the cockamamie synthesis procedures and be easy to obtain. The morphology, surface area, pore volume and elemental composition of Ti-CTS were revealed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) method and X-ray photoelectron spectroscopy (XPS). Tryptic digest products from several standard proteins and two real samples (non-fat milk and serum) were enriched using Ti-CTS to demonstrate the efficiency of this method. The results showed that this composite enables high sensitive and selective phosphopeptide enrichment from casein variants, non-fat milk and human serum. Furthermore, multi-phosphorylated peptides with three serine phospholated sites (S*S*S*) demonstrated high affinity to Ti-CTS. Hence, this method had great potential for future studies of complex phosphoproteomes and especially multi-phosphorylated peptides.
['Wu|Ting|T|', 'Shi|Jiani|J|', 'Zhang|Chuanjing|C|', 'Zhang|Lingfan|L|', 'Du|Yiping|Y|']
D048271:Chitosan D008855:Microscopy, Electron, Scanning D010748:Phosphopeptides D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization D014025:Titanium
Phosphopeptide enrichment Chitosan IMAC MALDI TOF MS