Real-World Levitation to Inspire Better Pharmaceuticals
Scientists at Argonne National Laboratory have discovered a way to use sound waves to levitate individual droplets of solutions containing different pharmaceuticals. At the molecular level, pharmaceutical structures fall into one of two categories: amorphous or crystalline. Amorphous drugs typically are more efficiently taken up by the body than their crystalline cousins. Getting pharmaceuticals from solution into an amorphous state, however, is no easy task. If the solution evaporates while it is in contact with part of a vessel, it is far more likely to solidify in its crystalline form. Argonne scientist Chris Benmore needed to find a way to evaporate a solution without it touching anything. Levitation or "containerless processing" can form pristine samples that can be probed in situ with the high-energy X-ray beam at Argonne's Advanced Photon Source. The acoustic levitator uses two small speakers to generate sound waves at frequencies slightly above the audible range – roughly 22 kilohertz.