Preparation of ion exchange mesoporous sieve DEAE-SBA-15 and its application to separation and purification of Der f 2 allergen in dermatophagoides farinae

Mesoporous silica SBA-15 was functionalized by 2-diethylamino-ethanol (DEAE) through the epoxide ring opening of 3-glycidyloxy-propyl-trimethoxy silane grafted on the silica surface (denoted as DEAE-SBA-15). Subsequently, DEAE-SBA-15 was used as the weak anion exchange matrix for chromatography to purify Der f 2 allergen from the spent culture medium extract of Dermatophagoides farinae, one of House dust mites that can cause heavy atopic diseases such as asthma and dermatitis. The structure of DEAE-SBA-15 was confirmed by ¹³C and ²⁹Si CP MAS NMR and other methods. By SDS-PAGE, Der f 2 was estimated to have a molecular weight of 14000 and appeared as the only separated protein band. The assay results of skin prick test showed that the allergic activity of Der f 2 was retained. The above results indicate that DEAE-SBA-15 materials are promising fixed-matrix candidates in liquid chromatography to purify proteins.