TY - JOUR
T1 - A Selective and Sensitive LC-MS/MS Method for Quantitation of Indole in Mouse Serum and Tissues
AU - Joshi, Vineet
AU - Chhonker, Yashpal S.
AU - Soni, Dhruvkumar
AU - Cunningham, Kelly C.
AU - Samuelson, Derrick R.
AU - Murry, Daryl J.
N1 - Funding Information:
The work was partially supported by the Fred & Pamela Buffett Cancer Center Support Grant from the National Cancer Institute under award number P30 CA036727 and by the National Institute on Alcohol Abuse and Alcoholism Grant R00-AA026336. The funders had no role in study design, data collection and analysis; decision to publish; or preparation of the manuscript.
Publisher Copyright:
© 2022 by the authors.
PY - 2022/8
Y1 - 2022/8
N2 - Indole is an endogenous substance currently being evaluated as a biomarker for ulcerative colitis, irritable bowel syndrome, Crohn’s disease and non-alcoholic fatty liver disease. A novel, selective, and sensitive method using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was developed for quantitation of indole concentrations in mouse plasma and tissues. Samples were prepared by protein precipitation using ice-cold acetonitrile (ACN) followed by injecting the extracted analyte to LC-MS/MS system. Indole was separated using Synergi Fusion C18 (4 µm, 250 × 2.0 mm) column with mobile phase 0.1% aqueous formic acid (A) and methanol (B) using gradient flow with run time 12 min. The mass spectrometer was operated in atmospheric pressure chemical ionization (APCI) positive mode at unit resolution in multiple reaction monitoring (MRM) mode, using precursor ion > product ion combinations of 118.1 > 91.1 m/z for indole and 124.15 > 96.1 m/z for internal standard (IS) indole d7. The MS/MS response was linear over the range of indole concentrations (1–500 ng/mL). The validated method was applied for quantitation of indole concentrations range in mouse lungs (4.3–69.4 ng/g), serum (0.8–38.7 ng/mL) and cecum (1043.8–12,124.4 ng/g). This method would help investigate the role of indole as a biomarker and understand its implications in different disease states.
AB - Indole is an endogenous substance currently being evaluated as a biomarker for ulcerative colitis, irritable bowel syndrome, Crohn’s disease and non-alcoholic fatty liver disease. A novel, selective, and sensitive method using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was developed for quantitation of indole concentrations in mouse plasma and tissues. Samples were prepared by protein precipitation using ice-cold acetonitrile (ACN) followed by injecting the extracted analyte to LC-MS/MS system. Indole was separated using Synergi Fusion C18 (4 µm, 250 × 2.0 mm) column with mobile phase 0.1% aqueous formic acid (A) and methanol (B) using gradient flow with run time 12 min. The mass spectrometer was operated in atmospheric pressure chemical ionization (APCI) positive mode at unit resolution in multiple reaction monitoring (MRM) mode, using precursor ion > product ion combinations of 118.1 > 91.1 m/z for indole and 124.15 > 96.1 m/z for internal standard (IS) indole d7. The MS/MS response was linear over the range of indole concentrations (1–500 ng/mL). The validated method was applied for quantitation of indole concentrations range in mouse lungs (4.3–69.4 ng/g), serum (0.8–38.7 ng/mL) and cecum (1043.8–12,124.4 ng/g). This method would help investigate the role of indole as a biomarker and understand its implications in different disease states.
KW - LC-MS/MS
KW - biomarker
KW - indole
KW - indole biodistribution
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U2 - 10.3390/metabo12080716
DO - 10.3390/metabo12080716
M3 - Article
C2 - 36005588
AN - SCOPUS:85137386565
SN - 2218-1989
VL - 12
JO - Metabolites
JF - Metabolites
IS - 8
M1 - 716
ER -