Particle Design

Microparticle design has been a focus of innovation in industry and academia in recent years. Several pharmaceutical development programs utilize particle engineering to design structured microparticles but suffer from a lack of adequate understanding and appropriate design tools. Structured microparticles enable novel products that address significant unmet needs. Areas of application include solid state stabilization of biologics and next-generation inhalation therapies.

Particle design research in the group is focused on several topics: physicochemical stabilization of labile pharmaceuticals and biopharmaceuticals; optimization of particle properties for aerosol drug delivery; and improvement of the consistency and uniformity of particle production processes. 

Available particle production tools include a Buchi Nano Spray Dryer with controlled environment enclosure, a Buchi B190 spray dryer with low humidity / low temperature drying capabilities, and a new custom research spray dryer.

Particle Formation

chain

An area of focus for the Particle Engineering Group is  particle formation from evaporating microdroplets  with dissolved or suspended phase; this process is  relevant in spray drying, aerosol drug delivery, and  atmospheric aerosols.

The group utilizes a droplet chain technique to study  evaporation and particle formation from  monodisperse droplets of 50-100 5m in a  well-controlled gas phase. A vibrating orifice aerosol  generator (VOAG) extends our range of scrutiny to  ~10 5m, and allows study of evaporation from solvents requiring pressurization (e.g. aerosol propellants).

Particle, Powder and Aerosol Analysis

Adequate physical characterization of structured microparticles is a significant challenge.  The Particle Engineering group utilizes low frequency shift Raman spectroscopy for detection and quantification of different chemical species, and differentiation of physical state (e.g. crystalline vs. amorphous, crystal polymorph) in combination powder formulations.  A custom designed uniaxial compression density analyzer allows us to study the packing and elastic behaviors of particles in bulk.

Additional in-house capabilities include particle sizing (cascade impaction, aerodynamic time-of-flight, photosedimentation) and Karl Fischer titration. We also collaborate with other researchers at the University to provide a full spectrum of physical characterization tools (SEM, SEM/EDX, FIB/SEM, DSC, XRD).