Diamond particles of 5-10 nm in size can be produced in large quantities by denonating oxygen-lean explosives in a closed chamber. They have numerous useful properties and are used in applications ranging from lubricants to drug delivery. Aggregation of diamond nanoparticles is limiting wider use of this important carbon nanomaterial because most applications require single separated particles. We demonstrate that dry media assisted attrition milling is a simple, inexpensive, and efficient alternative to the current ways of deaggregating of nanodiamond. This technique uses water-soluble nontoxic and noncontaminating crystalline compounds, such as sodium chloride or sucrose. When milling is complete, the media can be easily removed from the product by water rinsing, which provides an advantage when compared to milling with ceramic microbeads. Using the dry media assisted milling with subsequent pH adjustment, it is possible to produce stable aqueous nanodiamond colloidal solutions with particles <10 nm in diameter, which corresponds to 1-2 primary nanodiamond particles. The study of milling kinetics and the characterization of the produced nanodiamond colloids led us to conclude that aggregates of less than 200 nm in diameter, observed at the tail of the pore size distribution of milled nanodiamond, are loosely bonded and rather dynamic in nature. Color change observed in ND colloids upon shifting their pH toward the basic end allowed us to demonstrate that the coloration comes from the light interaction with colloidal particles and not from an increase in nondiamond carbon content.

This study showed that PyroButtons can provide very meaningful micro-environmental data that can be correlated to coating defects, and can aid in establishing a process design space for a given coating and tablet formulation.

The nano-sized fenofibrate demonstrates faster dissolution kinetics in aqueous media, simulating stomach environment, within the first 60 min as compared to the micronized form. The highest dissolution rate is achieved with the nano-sized fenofibrate when surfactants, such as sodium dodecyl sulfate or inclusion complex forming agents such as alpha-cyclodextrin, are used.

The objective of this study is to investigate processing challenges associated with the incorporation of Vitamin E TPGS (d-α tocopheryl polyethylene glycol 1000 succinate) into solid pharmaceutical dosage forms. For this work, a wet granulation process (high-shear and fluid bed) was used and Vitamin E TPGS was added as part of the binder solution during granulation. It was shown that Vitamin E TPGS can be incorporated into a prototype formulation at 10% w/w concentration without any significant processing challenges. However, the resulting granulations could only be compressed successfully at low tablet press speeds (dwell time ~100 ms). When compressed at low dwell times (<20 ms) representative of commercial tablet manufacturing, a significant loss in compactability was observed. In addition, several other tablet defects were observed. It was shown that intragranular incorporation of Aeroperl(®) 300, a granulated form of colloidal silicon dioxide, was able to overcome these compaction problems. The formulation consisting of Aeroperl(®) 300 showed significantly lower granule particle size, higher granule porosity and higher compactability as compared to the formulation without Aeroperl(®) 300.

The objective of this study was to improve the disintegration and dissolution characteristics of a highly water-soluble tablet matrix by altering the manufacturing process. A high disintegration time along with high dependence of the disintegration time on tablet hardness was observed for a high drug loading (70% w/w) API when formulated using a high-shear wet granulation (HSWG) process. Keeping the formulation composition mostly constant, a fluid-bed granulation (FBG) process was explored as an alternate granulation method using a 2 fractional factorial design with two center points. FBG batches (10 batches) were manufactured using varying disingtegrant amount, spray rate, inlet temperature (T) and atomization air pressure. The resultant final blend particle size was affected significantly by spray rate (p = .0009), inlet T (p = .0062), atomization air pressure (p = .0134) and the interaction effect between inlet T*spray rate (p = .0241). The compactibility of the final blend was affected significantly by disintegrant amount (p < .0001), atomization air pressure (p = .0013) and spray rate (p = .05). It was observed that the fluid-bed batches gave significantly lower disintegration times than the HSWG batches, and mercury intrusion porosimetry data revealed that this was caused by the higher internal pore structure of tablets manufactured using the FBG batches.