High affinity phosphopeptides enrichment and desalting of biological materials on newly engineered poly(glycidyl propargyl ether/divinyl benzene).

ABSTRACT

The new synthetic polymers have a key role to play in the separation science. The derivatization of these polymers has made them an efficient class of substrate, having unique properties and the selectively tailored surface chemistries for target molecules. The deeper and detailed characterization of complex sample types has become feasible due to the enhanced selectivity and sensitivity offered by these polymer materials. In present work, a bifunctional monomer glycidyl propargyl ether (GPE) is thermally polymerized with divinylbenzene to form poly(GPE/DVB). Some of the physical and chemical properties are characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR). The synthesized polymer is further derivatized to IMAC (immobilized metal ion affinity chromatography) and is investigated by loading different metal ions (Fe(3+), Ti(4+), Zr(4+), and La(3+)). The trypsin-digested products of phosphoproteins, such as casein, nonfat milk, egg yolk, and human blood serum, are used to explore its phosphopeptide enrichment ability from complex samples followed by the off-line MALDI-MS analysis. Furthermore, polymeric reversed phase (RP) is created by octadecyl amine (ODA) to be employed in the desalting of complex mixtures and the results are compared with commercially available ZipTip C-18 and Aspire RP30 Desalting Tip. Serum profiling of healthy and diseased samples demonstrates the potential of this new polymer to impart in the disease diagnosis. Ovarian carcinoma serum samples are used for the detection of phosphopeptides based biomarkers.