Table A1.

The gradient used in the chromatographic separation of amino acids where the solvents used were; A: water, B: acetonitrile, C: 500 mM ammonium acetate in water, and D: 5 (V)% formic acid in water.

Time, min	% A	% B	% C	% D
0	11	85	2	2
6.0	11	85	2	2
6.1	16	80	2	2
10.0	26	70	2	2
12.0	36	60	2	2
12.1	11	85	2	2
18.0	11	85	2	2