New Method Precisely Separates Mirror-Image GHRH Analogs for Drug Analysis

Growth Hormone-Releasing Hormone (GHRH) analogs are synthetic peptides used to stimulate growth hormone release, with potential applications in treating growth deficiencies or muscle wasting. However, many GHRH analogs can exist as enantiomers (mirror-image molecules), which often have different biological activities, potencies, or side effect profiles. Accurately separating and quantifying these enantiomers is crucial for drug development, quality control, and anti-doping efforts. Current analytical methods often lack the sensitivity or efficiency needed for complex samples. This study addresses the need for a highly efficient and sensitive method to separate enantiomeric GHRH analogs.

The developed method demonstrated exceptional capabilities for separating enantiomeric GHRH analogs. It achieved a remarkable separation efficiency, with theoretical plate numbers exceeding 150,000 plates/meter, and baseline resolution (Rs > 1.5) for all tested enantiomeric pairs. The integration of large volume sample staking significantly enhanced sensitivity, leading to a 50-fold improvement in detection limits compared to conventional CE, reaching limits of detection as low as 0.5 ng/mL. The method also showed excellent linearity (R² > 0.999) over a broad concentration range and high recovery rates, typically around 98%. The total analysis time per sample was efficiently reduced to less than 20 minutes. The method achieved an unprecedented 50-fold increase in sensitivity for GHRH analog enantiomers, enabling detection at 0.5 ng/mL with baseline resolution.