f. 5 μl of water was then spotted on each spot for 30 sec and removed using Whatman filter paper strips. This step was repeated once. g. 1-2 μl of SAP matrix was then applied to each spot and allowed to dry. h. The chip was then placed in the SELDI machine

a. 5 μl of 10 mM HCl was added to each spot on the chip and removed after 5 min. using Whatman filter paper strips. b. Washing was given by spotting 3 μl of water for 30 sec on each spot followed by removal using Whatman filter paper strips. This step was repeated two times. c. 10 μl of low stringency/ high stringency buffer was then added to the spot and kept in humid chamber for 5 min. followed by removal using Whatman filter paper strips. d. 3 μl of sample prepared in low stringency/ high stringency buffer was then added to the spot and incubated in humid chamber for 30 min. e. Washed the spot with 5 μl of low stringency buffer/ high stringency buffer/ buffer of pH 3.0/ pH 5.0/ pH 7.0 for 30 sec and removed using Whatman filter paper strips. This step was repeated five times.

Activation of CM10 (weak cation exchange ) array