Preparation of carboxyl‐functionalized silica core‐shell microspheres and their applications in weak cation exchange chromatography, heavy metal removal, and lysozyme enrichment

Chromatography is a technique of separation based on adsorption and/or interaction of target molecules with stationary phases. Herein, we report the design and fabrication of BTDA@SiO 2 core‐shell microspheres as a new class of stationary phase and demonstrate its impressive performance for chromatographic separations. The silica microspheres of BTDA@SiO 2 were synthesized by in situ method with 1,3,5‐benzenetricarboxaldehyde and 3,5‐diaminobenzoic to separate peptides and proteins on high‐performance liquid chromatography. The BTDA@SiO 2 core‐shell structure has a high specific surface area and retention factor of 4.27 and 8.31 for anionic and cationic peptides, respectively. The separation factor and resolution were high as well. A typical chromatogram illustrated nearly baseline resolution of the two peptides in less than 3 min. The BTDA@SiO 2 was also highly stable in the pH range of 1 to 14. Furthermore, the prepared BTDA@SiO 2 core‐shell material not only be used for chromatographic separation but also as heavy metal removal from water. Using a BTDA@SiO 2 , we also achieved a lysozyme enrichment with a maximum saturated adsorption capacity reaching 714 mg/g. In summary, BTDA@SiO 2 has great application prospects and significance in separation and purification systems.