BONDED PHASE OF SILICA FOR SOLID PHASE EXTRACTION

摘要

A solid phase-bonded silica prod. of formula (I) is new. In (I), (a) is a backbone of a silica gel or controlled pore glass; X is O, S, - O-CH2-CH(OH)-CH2-O- or -O-CH2-CH(OH)-CH2-S; R and R1 are each H, C1-3 alkyl or (CH2)m COOR3; R2 and R3 are each C1-4 alkyl; n is 2-5; p is 0-1; m is 1-4. (I) is useful for a cleanup of urine samples for analyzing cannabinoids in urine.