A novel method to determine residual detergent in biological samples post endotoxin reduction treatment and evaluation of strategies for subsequent detergent removal

•Detergent extraction is a robust method for endotoxin removal from protein solutions; residual detergent removal challenging•Residual detergent amounts can be quickly determined using the Endosafe™ endotoxin detection apparatus•The residual detergent can be effectively removed using detergent spin columns and polystyrene beads

Endotoxin removal using detergent washes and extractions are well-established, efficient, and cost-effective methods; however, removing residual detergent post treatment has been shown to be a challenge. In this communication, we show a simple and fast method for determining the detergent concentration in a protein solution post treatment and highlight strategies for detergent removal to achieve levels below the critical micelle concentration (CMC), the minimum concentration at which detergent micelles form.