Metabolmic Analysis by Ambient Ionization Techniques

Method(s) of Analysis:

  • Desorption Electrospray Ionization (DESI) – optimal for condensed phase samples
  • Extractive Electrospray Ionization (EESI) - optimal for solution phase samples

Both offer:

  • Rapid Analysis (High Throughput)
  • Minimal Sample Preparation
  • Sensitive
  • Reproducible

Key Findings:

Analysis of Healthy and Diseased Lung Cancer Mice Urine by DESI

  • Results validated with NMR analysis
  • Able to distinguish diseased (tumor) from healthy mice
  • Principal component analysis (PCA) used to identify potential biomarkers
  • Over 80 metabolites identified by DESI

Urine Analysis of Inborn Errors of Metabolism (IEM) by DESI

  • Using PCA  six IEM were distinguished from control urine patient samples
  • Correlation of key compounds with metabolic pathways
  • Potential tool for better understanding rare diseases

Exploration of the Effect of Diet on Rat Urine by EESI

  • Able to distinguish rat urine based on three different diets
  • Identified metabolic pathway more influenced  by diet
  • Potential method to eliminate diet influence in biosamples



  • Haiwei Gu, Huanwen Chen, Zhengzheng Pan, Ayanna U. Jackson, Nari Talaty, Bowei Xi, Candice Kissinger, Chester Duda, Doug Mann, Daniel Raftery and R. Graham Cooks, "Monitoring Diet Effects from Biofluids and Their Implications for Metabolomics Studies", Anal. Chem., 2007, 79(1), 89-97, doi: 10.1021/ac060946c
  • Zhengzheng Pan, Haiwei Gu, Nari Talaty, Huanwen Chen, Narasimhamurthy Shanaiah, Bryan E. Hainline, R. Graham Cooks, Daniel Raftery, "Principal component analysis of urine metabolites detected by NMR and DESI-MS in patients with inborn errors of metabolism", Anal. Bioanal. Chem., 2007, 387(2), 539 doi: 10.1007/s00216-006-0546-7
  • Huanwen Chen, Zhengzheng Pan, Nari N. Talaty, R. Graham Cooks and Daniel Raftery, "Combining Desorption Electrospray Ionization Mass Spectrometry and Nuclear Magnetic Resonance for Differential Metabolomics without Sample Separation", Rapid Comm. Mass Spectrom., 2006, 20, 10, 1577-1584, doi: 10.1002/rcm.2474