文摘
Concentration determination by HPLC analysis is often utilized in pharmaceutical development activities. Traditionally, manual dilutions employing volumetric glassware have to be performed to obtain accurate concentration results. To circumvent this, an automated dilution method for the Agilent 1100 HPLC system has been developed to dilute and inject the samples online. After appropriate calibration, quantitative analysis can be achieved by placing the solution samples directly into HPLC vials without additional manipulation. This method is successfully applied to active pharmaceutical ingredient (API) solubility measurements and concentration determinations of routine mother liquor samples in the range of 0.1鈥?00 mg/mL. It is particularly useful in crystallization development where obtaining accurate concentration information quickly drives down development time and material requirements.