Case Studies

Case Study 3 : Near Infrared Method in Early-Stage Formulation Development

Case Study 2 describes the use of an NIR-SPCA method in process validation. The same method can also be used for speeding up the formulation development process. When a formulation scientist engages in a formulation development project, he or she usually seeks the support from analytical chemists and hope for a fast turnaround time. But traditional analysis (e.g. by HPLC) is time-consuming and can only provide limited information (e.g. API concentration). NIR is fast, non-destructive and information-rich but is limited by the availability of calibration models. SPCA greatly simplifies the modeling process. In a real world example, a low dose tablet formulation was being developed using a direct compression process. Suitable excipients that could improve manufacturing ability were to be identified. To create the SPCA model, samples from the feasibility batches were collected and analyzed by transmission NIR. A quick principal component analysis was performed on the data set. It was found that the systematic variations in the tablets samples could be represented by a handful of principal components (PCs or latent variables). One of the PCs was found to be directly related to the API concentration and the corresponding PC scores could be used directly for assessing content uniformity of the tablets. Thus an SPCA model was created and later used for analyzing samples from multiple batches of development samples.