Setting Ideal Lubricant Mixing Time for Manufacturing Tablets by Evaluating Powder Flowability

Computer-aided optimization of carbidopa/levodopa orally disintegrating tablets

OBJECTIVE

This study aimed to optimize the formulation of carbidopa/levodopa orally disintegrating tablets (ODTs) in order to improve their disintegration performance, and facilitate easier medication intake for Parkinson's patients.

METHOD

The response surface methodology (RSM) was used to optimize the formulation, with the content of cross-linked polyvinylpyrrolidone (PVPP), microcrystalline cellulose (MCC), and mannitol (MNT) as independent variables, and disintegration time as the response parameter. Python was utilized to model Carr Indices and mixing time to determine the suitable mixing time. Direct compression (DC) was used for the preparation of ODTs.

RESULT

The optimization process resulted in the following values for the independent variables: 7.04% PVPP, 22.02% MCC, and 16.21% MNT. By optimizing the mixing time using Python, it was reduced to 14.19 min. The ODTs prepared using the optimized formulation and a mixing time of 14.19 min exhibited disintegration times of 16.74 s in vitro and 17.63 s in vivo. The content uniformity of levodopa and carbidopa was found to be 100.83% and 99.48%, respectively.

CONCLUSION

The ODTs optimized using RSM and Python demonstrated excellent disintegration performance, leading to a decrease in the time the drug exists in solid form in the oral cavity. This improvement in disintegration time reduced the difficulty of swallowing for patients and enhanced medication compliance, while still ensuring that ODTs prepared by DC had sufficient mechanical strength to meet storage and transportation requirements.

Direct Compaction Drug Product Process Modeling

Most challenges during the development of solid dosage forms are related to the impact of any variations in raw material properties, batch size, or equipment scales on the product quality and the control of the manufacturing process. With the ever pertinent restrictions on time and resource availability versus heightened expectations to develop, optimize, and troubleshoot manufacturing processes, targeted and robust science-based process modeling platforms are essential. This review focuses on the modeling of unit operations and practices involved in batch manufacturing of solid dosage forms by direct compaction. An effort is made to highlight the key advances in the past five years, and to propose potentially beneficial future study directions.

Utility of Microcrystalline Cellulose for Improving Drug Content Uniformity in Tablet Manufacturing Using Direct Powder Compression

Direct powder compression is the simplest tablet manufacturing method. However, segregation occurs when the drug content is low. It is difficult to assure drug content uniformity in these cases. In this study, we evaluated microcrystalline cellulose (MCC) as a segregation inhibitor in pharmaceutical powders. We assessed the influence of MCC concentration and mixing time on the physical properties of tablets. The tablet formulation comprised acetaminophen, lactose hydrate, cornstarch, MCC (0%, 10%, or 20%), croscarmellose sodium, and magnesium stearate (Mg-St). All powders except Mg-St were premixed for 5, 15, or 25 min. Mg-St was then added and mixed for 5 min to prepare nine pharmaceutical powders. Flowability index and practical angle of internal friction were measured. Tablets were also prepared, and their weight variation, hardness, friability, disintegration time, and drug content variation were evaluated. MCC slightly decreased pharmaceutical powder flowability. Tablet hardness increased and disintegration time decreased with increasing MCC concentration. MCC mixed for ≥ 15 min also significantly lowered drug content variation. A contour plot was prepared to assess the effect of MCC concentration and mixing time on the physical properties of tablets. It was determined that tablets with 50-80 N hardness, ≤ 3.5 min disintegration time, and ≤ 3% drug content variation can be prepared when MCC concentration is 6.5-8.5% and the mixing time is 19-24 min. Therefore, MCC is effective as a segregation inhibitor, and the addition of MCC to tablet formulation improves drug content uniformity.