“…Amitriptyline was oxidized to anthraquinone prior to measurement (91) while hydrazine in plasma and urine was reacted with p -methoxybenzaldehyde to form the hydrazone derivative (251). An automated procedure for the assay of cefazolin employs a reaction with hydroxylamine and a double-probe sampling procedure (98). Complex formation was utilized for the determination of steroid sulfates (134), for the assay of alkaloids (226), and for the determination of ampicillin in powders and formulations (151).…”