On-line solid phase extraction using organic-inorganic hybrid monolithic columns for the determination of trace β-lactam antibiotics in milk and water samples

► A rapid and simple on-line solid phase extraction (SPE) was developed. ► The novel epoxy-based column was used as SPE sorbent to monitor β-lactam. ► It has a safe, efficient, easy to operate, easy to realize advantages of automation. ► Validation was performed at spike concentrations of 10, 50 and 500 ng mL−1. ► Accuracy, precision, matrix effect, linearity, LOD and LOQ were assessed.