Gadolinium oxide: Exclusive selectivity and sensitivity in the enrichment of phosphorylated biomolecules

Abstract

Selectivity and sensitivity define the dynamic applicability of separation and enrichment techniques. Owing to proteome complexity, numbers of separation media have been introduced in phosphoproteomics. Complex samples are pretreated to make the low-abundance molecules detectable by mass spectrometry. Gadolinium oxide nanoparticles, offering mono- and bi-dentate interactions, are optimized to capture the phosphopeptides. Selectivity of 1:11 000 is achieved for digested β-casein phosphopeptides in bovine serum albumin digest background using gadolinium oxide nanoparticles. The limit of detection goes down to 1 attomole. With the optimized sample preparation protocol, gadolinium oxide nanoparticles enrich phosphopeptides of κ-casein (Ser and Ser ) from digested milk sample, fibrinogen alpha chain phosphopeptide (Ser ) along with four hydrolytic products of Ser -modified phosphopeptides from serum.

Facile synthesis of Ti4+-immobilized affinity silica nanoparticles for the highly selective enrichment of intact phosphoproteins

“…Therefore, enrichment of phosphopeptides from protein digests before MS analysis can solve this problem effectively . To date, diverse approaches including SCX , immobilized metal ion affinity chromatography , and metal oxide affinity chromatography have been introduced for separation and enrichment of phosphopeptides.…”

Widening the Bottleneck of Phosphoproteomics: Evolving Strategies for Phosphopeptide Enrichment

“…Surprisingly, selectivity bias for mono‐ and multiply‐phosphorylated peptides was found to be negligible between TiO 2 and ZrO 2 . The oxides for RE elements, such as La 2 O 3 , Gd 2 O 3 , Sm 2 O 3 , and CeO 2 have also been used for phosphopeptide enrichment, and have been shown to be highly selective and sensitive (Cheng et al, 2011; Jabeen et al, 2016, 2015, 2017). One thing to note is that besides phosphopeptide enrichment, CeO 2 also catalyses the cleavage of phosphate ester bond, resulting in the dephosphorylation of phosphopeptides (Tan et al, 2008).…”

Preparation of zirconium arsenate‐modified monolithic column for selective enrichment of phosphopeptides

“…To date, a number of strategies, including immobilized metal ion affinity chromatography (IMAC) [7][8][9][10][11][12], metal oxide affinity chromatography (MOAC) [13][14][15][16][17][18], ion exchange chromatography [19][20][21], and molecularly imprinted polymers [22][23][24][25][26], have been developed for the selective enrichment of phosphopeptides. IMAC is one of the widely applied techniques for phosphopeptide enrichment.…”