Post-synthesis of covalent organic frameworks as a hydrophilic platform for specific detection of egg ovalbumin under physiological pH

Ovalbumin (OVA) is an important protein source in our daily life. Unfortunately, the food safety problem has become more and more serious, such as protein allergy and contaminated protein. Therefore, it is necessary to detect vital proteins efficiently and rapidly. Mass spectrometry (MS) is a powerful tool for the detection of proteins. Herein, dual amino acids functionalized covalent organic frameworks containing disulfide covalent bonds ( [email protected] [email protected] , where G is glutathione and C is cysteine) were facilely prepared for OVA enrichment through hydrophilic interaction liquid chromatography (HILIC) under physiological pH. The results showed that [email protected] [email protected] had displayed sensitive detection (0.1 fmol), good selectivity (OVA: BSA = 1:100), adsorption capacity (311 mg/g), stability, reproducibility, linearity, LOQ level (42 μg/mL) and recovery ratio (64.83 %) for OVA. [email protected] [email protected] also demonstrated satisfactory purification ability in the enrichment of egg white, indicating that [email protected] [email protected] had great potential in the enrichment of protein from complex samples.