January 6, 2026 — Southwest Research Institute has upgraded its nuclear magnetic resonance (NMR) laboratory to offer robust chemical analysis of organic compounds used in drug discovery and development.
Through internally funded research, SwRI used the new laboratory to compare quantitative NMR (qNMR) to high-performance liquid chromatography (HPLC), a conventional method used to determine the purity of active pharmaceutical ingredients (APIs). SwRI’s research found that qNMR can be more cost effective and faster than HPLC for API quantification in certain applications.
“In the early phases, when you want to get drugs into trial as fast as possible, qNMR has the potential to dramatically reduce the time and cost of accurately quantifying APIs and impurities,” said Dr. Shawn Blumberg, an SwRI lead scientist who worked on the project. “For late-stage development, once a full analytical method has been developed, qNMR has shown that it can be used as a complementary method to HPLC for confirming the weight-for-weight purity of the target compound, providing more confidence in dose calculations and leading to a better overall product.”
Other studies have shown qNMR to be useful in determining the weight-for-weight purity of a variety of organic compounds, but publicly available data have been sparse in a context that compares qNMR to HPLC for pharmaceutical development. SwRI funded the internal research to help the team develop a qNMR technique to allow for accurate analysis and quantitation without the high material burden of standard methods, while providing direct comparisons to HPLC.
NMR instruments use large magnets to study the properties of atomic nuclei. Through electromagnetic radiation, NMR provides atomic data about organic compounds, which helps to determine the structures of small-molecule drugs and other chemicals.
HPLC is an analytical technique that separates and quantifies chemical components in a liquid mixture. It relies on the use of solvents and stationary phases to fractionate compounds based on specific properties. Detection is typically performed by generating visual spectral profiles to identify and quantify the target analytes. Due to the complexity of the method, HPLC often requires multiple iterative experiments using carefully optimized analytes and conditions over time to achieve accurate and reproducible results.
“Though HPLC has become the gold standard of quantitative API analysis, the procedure requires significant amounts of material to perform a myriad of experiments,” said Dr. Christopher Dorsey, an SwRI senior research scientist who served as primary investigator. “HPLC methods must be developed and validated for each compound at each step along the synthetic route, taking several weeks and increasing product development timelines, expense and additional synthesis to provide material necessary for assay development.”
NMR can not only identify the product of interest but also residual solvents and other organic impurities. Using a known amount of a commercially available reference standard, quantitative information about the purity of the analyte can be obtained without needing a reference standard of the exact same compound for comparison.
SwRI’s Pharmaceutical and Bioengineering Department maintains FDA-inspected facilities that meet current good manufacturing practice (CGMP) standards that are required to make clinical supplies.
For more information, visit Nuclear Magnetic Resonance (NMR) Laboratory or contact Robert Crowe, +1 210 522 4630, Communications Department, Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238-5166.