Measurement of residual isopropyl alcohol in loracarbef by near-infrared reflectance spectroscopy

A near-infrared reflectance spectroscopic (NIRS) method was developed and v alidated for the measurement of isopropyl alcohol (IPA) in loracarbef. A pa rtial least-squares calibration was established for a set of 30 samples by correlation to the gas chromatographic reference method. The NIRS method wa s validated for selectivity, accuracy, precision, and robustness. The inter mediate precision of the method was estimated to be 0.17%, comparing favora bly to the precision of the GC reference method. During validation of the r obustness of the method, sample analysis technique was found to be responsi ble for a statistically significant analyst bias. The bias was eliminated b y standardization of the technique. Additionally, samples were found to los e IPA when opened to the laboratory atmosphere.