Determination of Amino Acids in Human Pancreas Tissue Sections Using Liquid Chromatography Tandem Mass Spectrometry

A new analytical method was developed for the determination of 35 different amino acids in human pancreas tissue sections embedded in O.C.T. by liquid chromatography tandem mass spectrometry with precolumn derivatization. An AccQ-Tag was selected as a derivatization reagent because it could avoid the ion suppression caused by matrix compounds in the pancreas tissue. This new method uses two different internal standards during the pretreatment processes to achieve good accuracy and high sensitivity, as well as a multiple reaction monitoring time segment program during the acquisition process. This method was fully validated for 35 different amino acids and showed a good linearity of calibration curve (r(2)>0.993), with a lower limit of quantification in the range of 0.01-0.75 mu M. Furthermore, this method was applied to the analysis of 35 different amino acids in human pancreas tissue sections, and successfully allowed for the determination of 27 of these compounds. The accuracy of our newly developed method was estimated to be in the range of 87%-115% based on the results of a recovery test. This method therefore represents a powerful analytical platform for the analysis of human tissue sections and could be used to investigate the mechanism of pancreatic disease.