(126a) Electrostatics of Dry Powder Aerosols for Inhalation

Electrostatics of pharmaceutical aerosols for inhalation is a relatively new research area. Particle charges have been proposed to potentially influence deposition in the lungs but no conclusive in vivo data have been reported. Investigation of the relationship between the formulation and aerosol charging is required to further explore this area. The modified electrical low pressure impactor (ELPI) and bipolar charge analyser (BOLAR) have been used to measure the size and electrostatic charge of particles generated from dry powder inhalers (DPIs). DPIs are commonly used to deliver drugs to the lungs. The powder is dispersed by the inhalation effort of the patient. Net charges are generated through triboelectrication during aerosolisation. These charges were found to be formulation- and humidity-dependent [1, 2], as well as bipolar [3, 4]. The knowledge gained may be useful in the development of pharmaceutical aerosols and pulmonary drug delivery in the future.

References

1. Philip Chi Lip Kwok, Hak-Kim Chan (2008) Effect of relative humidity on the electrostatic charge properties of dry powder inhaler aerosols. Pharmaceutical Research, 25(2): 277-288.
2. Jennifer Wong, Philip Chi Lip Kwok, Tim Noakes, Ali Fathi, Fariba Dehghani, Hak-Kim Chan (2014) Effect of crystallinity on electrostatic charging in dry powder inhaler formulations. Pharmaceutical Research 31(7): 1656-1664.
3. Jennifer Wong, Yu-Wei Lin, Philip Chi Lip Kwok, Ville Niemelä, John Crapper, Hak-Kim Chan (2015) Measuring bipolar charge and mass distributions of powder aerosols by a novel tool (BOLAR). Molecular Pharmaceutics 12(9): 3433-3440.
4. Jennifer Wong, Philip Chi Lip Kwok, Ville Niemelä, Desmond Heng, John Crapper, Hak-Kim Chan (2016) Bipolar electrostatic charge and mass distributions of powder aerosols – Effects of inhaler design and inhaler material. Journal of Aerosol Science 95: 104-117.