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A new thermosensitive chromatographic materials,poly(N-isopropylacrylam-ide-co-2-(diethylamino)ethylmethacrylateco-N-tert-butylacrylamide)[poly(NIPAAm-co--DEAEMA-co-tBAAm)] grafted silica featuring thermally switchable property was prepared via SI-ATRP and then employed for the enrichment and separation of biomolecules such as adenosine phosphates and proteins via a temperature-controlled capture and release process.To achieve the desired thermosensitivity,the grafting configurations of the copolymer were optimized and characterized by high molecular weight,dilute chain density,and hydrophilic interface.Enhanced thermosensitivity facilitated fast and substantial changes in surface properties and chains conformation under temperature stimulus.The thermally switchable property enabled broader applications for the copolymer,such as enrichment of adenosine phosphates.At pH 7.3,ATP is selectively captured at temperatures below 25 ℃ and rapidly released by increasing the temperature to 50 ℃.The capture and release of adenosine phosphates is found to be pH-dependent.Both ADP and ATP are selectively captured at pH 7.0,and their stepwise release is achieved by switching the temperature from 20 to 40 ℃,and then from 40 to 50 ℃.Furthermore,the selective capture modulated by temperature was examined with 8 proteins.Only HSA and BSA were selectively adsorbed at 40 ℃,and rapidly released at 10 ℃,and a 4.36-fold enrichment of HSA was obtained after 5 injections.Application in proteomic analysis as a new sample preparation strategy,the capture and release process modulated by temperature was shown to double the number of LC/MS/MS-identified proteins from human serum,and scores and coverage ratios for most of the identified proteins increased dramatically as well.This convenient and fast technology provides great practical advantages over conventional approaches by eliminating the time-consuming need for buffer-changing steps.A new thermoresponsive boronate affinity chromatographic material,poly(N-isopropylacrylamide-4-vinylphenylboronic acid)poly(NIPAAm-co-VPBA)grafted silica featuring thermally switchable property,was prepared via SI-ATRP and successfully employed for the thermally modulated capture/release of cis-diol biomolecules including adenosine and horse radish peroxidase.The capture/release was achieved by the regulation of surface properties of stationary phase with simpler adjustment to the temperature instead of the conventional need to change the pH of mobile phase.However,changing mobile phase must be utilized for the release of captured cis-diol compounds using ordinary boronate affinity chromatographic materials.The capture of the adenosine depended on stronger binding of VPBA units in copolymers,and NIPAAm moieties are the active components for the thermally modulated release.After 6 repetitions of injections,the enrichment efficiency for adenosine went up to 95.8%.The results indicated that the prepared material can be effectively used for the selectively enrichment and separation of cis-diol biomolecules via the temperature-controlled capture and release process.