Phosphonic Acid Functionalized Periodic Mesoporous Organosilicas and Their Potential Applications in Selective Enrichment of Phosphopeptides

Abstract

Phosphonic acid functionalized periodic mesoporous organosilicas were synthesized by co-condensation of 1,2-bis(trimethoxysilyl)ethane and diethoxyphosphorylethyl-triethoxysilane in acidic medium using Brij-76 as a template. Structural characterizations showed that the mesoporous materials with 2-D hexagonal mesostructures could be obtained in the presence of an inorganic salt, NaCl. The results of transmission electron microscopy revealed that the materials synthesized with NaCl/Brij-76 mass ratios of 3 and 4 had extensive structural defect holes in the nanochannels. After coordinating metal ions (Zr 4+ and Fe 3+ ) with phosphonic acid in the mesopore, the materials were applied as the potential immobilized metal affinity chromatographic adsorbent for the selective enrichment of phosphopeptides. Because of the stronger affinity interaction between the coordinated metal ions and the phosphoryl groups of phosphopeptides, the higher surface area, and the unique mesoporous structure, the capture of the phosphopeptide on the phosphonic acid functionalized periodic mesoporous organosilicas were much more efficient than that on the commercial POROS-20 beads.

Recent advances of mesoporous materials in sample preparation

“…One is self-assembling approach using soft-templates, similar to the synthesis of silica based materials, inorganic precursors (metal alkoxides or chlorides, carbon precursors) are usually used for self-assembly with amphiphilic block copolymer templates via chemical interactions including electrostatic attraction, hydrogen bonding, and hydrophobic/hydrophilic interactions [19]; another is using nanocasting strategy that takes highly ordered silica mesoporous materials (such as SBA-15, MCM-48) as 'hard template' and the inorganic precursors as the filling agents to fill up the mesochannels of 'hard template' to cast the mesostructured non-siliceous inorganic materials. Various nonsiliceous inorganic mesoporous materials including ZrO 2 , TiO 2 , HfO 2 , Gr 2 O 3 , Au, Pd, CMK-1 and CMK-3 have been successfully prepared by these methods [18,[20][21][22].…”

“…However, conventional IMAC adsorbents are modified with IDA or NTA as ligands to immobilize Ga 3+ or Fe 3+ , and still lack enough specificity to phosphopeptides due to the significantly unselective co-enrichment of highly acidic peptides, which results in low selectivity and sensitivity for targeted phosphopeptides. In our lab, Fe 3+ and Zr 4+ phosphate functionalized periodic mesoporous organosilicas with ordered 2D hexagonal mesostructures, high specific surface area and large pore volume have been applied to enrich phosphopeptides, which showed higher intensities and signal/noise ratios of the enriched phosphopeptides than that of commercial POROS 20 loaded with the same metal ion [22]. Ti 4+ incorporated hexagonal mesoporous silica (Ti-HMS) with relative high Ti-content (2 and 8 mol%) are successfully synthesized in our lab for the enrichment of phosphopeptides [95].…”

Functionalized periodic mesoporous organosilicas: Hierarchical and chiral materials

“…We have previously reported the synthesis of BPMOs with bimodal porous systems by post-treatment-induced reconstruction [17,18]. Phosphonate-ester-functionalized mesoporous organosilicas were first synthesized by cocondensation of 1,2-bis(trimethoxysilyl)ethane (BTME) and diethoxyphosphorylethytriethoxysilane (PETES) around poly(ethylene oxide)-block-poly(propylene oxide)-blockpoly(ethylene oxide) (P123) micelles.…”

“…Due to the low degree of cross-linking of the framework, reconstruction of the mesostructure during the treatment results in the formation of a bimodal porous structure (the sizes of the primary and secondary pores are 6.5 and 65 nm, respectively). This method can be also extended to the synthesis of similar mesoporous organosilicas with hierarchical structure (the existence of extensive structural defect holes in the nanochannels) using polyoxyethylene(10) stearyl ether (Brij-76) as a surfactant template [18]. After coordinating metal ions (Zr 4+ and Fe 3+ ) to the phosphonic acid groups in the mesopores, the materials were employed as an immobilized metal affinity chromatographic (IMAC) adsorbent for the selective enrichment of phosphopeptides.…”

Micro-extraction of Xenobiotics and Biomolecules from Different Matrices on Nanostructures

“…Various mesoporous silica materials such as the already cited MCM-41 with two-dimensional hexagonal crystal (p6mm)(82), or SBA-12 with three-dimensional hexagonal crystal (P6 3 /mmc)(170), or SBA-16 with three-dimensional cubic (Im3m)(171), lamellar(172), cellular foam(83) can be prepared with different pore sizes by using different types of surfactants, additives, reaction temperatures and medium (basic/acidic).The details of the synthesis strategies of various types of non-silica inorganic based mesoporous materials including ZrO 2 , TiO 2 , HfO 2 , Gr 2 O 3 , Au, Pd, carbon CMK-1 and CMK-3 also have been explained in many research papers(173)(174)(175)(176). After synthesis, the characterization of mesoporous materials is carried out with the same techniques as explained above for morphology, qualitative and quantitative determination and functionalization of silica NPs.Moreover, the specific surface areas and porous structures of the samples can be determined by analysing the results of nitrogen sorption at 77 K in a Micromeritics apparatus.…”