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Due to the great complexity of proteomes,the high efficient separation of proteins and peptides plays significant roles in proteome analysis.HPLC has been widely used for protein and peptide separation,and monoliths have been considered as "fourth-generation stationary phase",with benefits of high permeability,fast mass transfer,and low backpressure.Organic-silica hybrid monoliths combined the advantages of polymer monoliths and silica monoliths.However,the framework structure mainly consists of Si-0 bonds,leading to the hydrolysis of Si-0 bonds under the acid or alkaline conditions,the nonspecific adsorption of residual silanol groups and the difficulty in functionalization of the pore wall,so the stability,peak capacity and separation efficiency should be further improved.In our work,bridged organosilane precursors were used to develop novel organic-silica hybrid monoliths,so that-Si-R-Si-structures can be formed in the frameworks and the functional organic groups act as part of the pore wall,improving the pore structures and adjusting the physical and chemical properties.With amine-bridged silicane and octyltriethoxysilane,C8-functionalized hybrid monoliths were developed for nanoHPLC separation of proteins.Four standard proteins were well separated and detected by UV with symmetrical and sharp peak,showing high separation resolution and efficiency.The peak width at half height is only 3.75 s and high peak capacity of 377 was achieved.Furthermore,the monoliths were applied to "top-down" proteomic research.Histones were successfully separated and identified by MS.Besides,with ethylene-bridged silicane and vinyl trimethoxysilane,the monolith with vinyl groups distributed in both the frameworks and pore channels was prepared and then modified with C18 groups via thiol-ene click chemical reaction.By such monolith,five standard peptides were successfully separated with high resolution and good reproducibility.Moreover,tryptic digestion of BSA and E.coli was separated by such monoliths and identified by ESI-MS/MS,compared with the analysis using C18 packed capillary column.In summary,based on the bridged organosilane precursors,several kinds of organic-silica hybrid monoliths,with good stability and special functional groups in the formwork,were developed for protein and peptide separation,showing good reproducibility,high efficiency and high peak capacity.