Improvements for the visualization of low-molecular weight protein and peptides of human tears using MALDI.
Many low-molecular weight proteins and peptides in human tears are potentially bioactive proteins but the range and number of these is yet to be fully characterized. A number of different sample preparation techniques were used to maximize the visualization of peptides from reflex tears. Samples were pretreated using precipitation and filtration techniques prior to analyses using MALDI-TOF MS. Peptides were searched for between 700 to 4000 m/z. Sample dilution in several different buffer systems followed by filtration with a 30-kDa cutoff filter and C18 reverse phase microcolumn purification produced significantly (p = 0.049) more peaks in tears than other methods used to prepare tears prior to MALDI-TOF MS. This study has established a technique for optimizing the visualization of naturally occurring peptides in tears.
Nguyen-Khuong
Terry
T
Minomic Pty Ltd, Frenchs Forest, NSW, Australia.
Fitzgerald
Anna
A
Zhao
Zhejun
Z
Willcox
Mark
M
Walsh
Bradley J
BJ
D000328:Adult; D006801:Humans; D008970:Molecular Weight; D010455:Peptides / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013666:Tears / Q000737:chemistry*
D010455:Peptides; D011506:Proteins