Determination of Melamine in Milk and Dairy Products

Method:	SPE
Matrix:	Milk
Application No.:	101723
Columns:	ProElut PXC 60 mg / 3 mL 50/pk
Cat No.:	68203
Sample Pretreatment:	1. Sample preparation 1.1. Milk and milk powder Dilute milk (2 mL) or milk powder (1 g) with 5 mL of trichloroacetic acid aqueous solution (10 g/L) in a 15 mL centrifuge tube, add 0.5 mL lead acetate aqueous solution (22 g/L) and 2 mL chloroform, vortex and centrifuge 2 min at 3,000 rpm, collect supernatant, add 5 mL trichloroacetic acid aqueous solution (10 g/L) to residue, vortex and centrifuge 2 min at 3,000 rpm, collect and combine supernatants. 1.2. Cream candy and cookies Grind 1 g sample with sand into powder in a mortar, add powder to a 50 mL centrifuge tube, rinse the mortar with 15 mL of trichloroacetic acid aqueous solution (10 g/L), transfer solution to centrifuge tube then shake, add 1 mL lead acetate aqueous solution (22 g/L) and 5 mL chloroform, vortex and centrifuge 2 min at 3,000 rpm, collect supernatant, add 15 mL trichloroacetic acid aqueous solution (10 g/L) to residue, vortex and centrifuge 2 min at 3,000 rpm, collect and combine supernatants. 2. Sample purification ProElut™ PXC 60 mg / 3mL (Cat#68203) Condition: 3 mL MeOH / 3 mL H₂O Load: supernatant Wash 1: 3 mL deionized water Wash 2: 3 mL MeOH Elute: 3 mL 5 % NH₄OH in MeOH Reconstitute: Evaporate at 50 ºC by N₂, reconstitute to 1 mL with MeOH:H₂O (20:80, V / V) solution12 mL reservoir (Cat#4810) and adaptor (Cat#4803) is available for large volume sample
Conditions:	HPLC method Column: Inspire™ 5 µm C18, 150 x 4.6 mm (Cat#81001) Mobile Phase : Buffer:MeCN = 92:8 Flow Rate: 1.0 mL/min Temperature: 30 ºC Detection: UV 240 nm Injection Volume: 20 µL Buffer: dilute 2.02 g sodium 1-heptanesulfonate and 2.10 g citric acid with water to total volume 1,000 mL
Author:	Dikma Technologies Inc.
Keyword:	Melamine, Dairy Products, Milk, SPE, PXC, Inspire