Barbas is known for her research on metabolomics, a field she was first introduced to while she was a Marie Curie fellow. Her early research centered on the analysis of vitamins and development of chemical methods to analyze compounds such as caffeine. Her subsequent research has developed methods to analyze organic compounds in pharmaceutical drugs and foods, and defined biomarkers for diseases such as leukemia and Parkinson's disease. She is also known for defining quality assurance protocols for metabolomics data analysis and establishing workflows to analyze metabolomics data.