November 2021
Inhalation 1-2-3 A brief update from Inhaltion Magazine.


Why is it so difficult to simulate lung dissolution and absorption in vitro?
imageFor many years, there has been a demand for an in vitro dissolution and absorption model for inhalable formulations that will be accepted by the scientific community and regulatory agencies. Many of the methods used today were originally designed for tablets. However, there are multiple parameters that affect dissolution and absorption processes in the lung. Inhalation Sciences has designed an artificial lung/blood barrier, taking the following into account:
  • Aerosol concentration/surface area
  • Temperature regulated air/liquid interface simulating the lung/blood barrier
  • Mucus layer on the luminal side, on which particles deposit
  • Dissolved particles passing through a membrane to the "vascular" side are absorbed by simulated blood. Sink conditions occur in this single-pass perfusate.
  • Sampling with a fraction collector generating Cmax and Tmax data
This dissolution module provides a simplified but standardized method, simulating lung conditions and generating physiological-like data for ranking and identifying the best drug candidates.

Inhalation Sciences
Sweden: +46 705 625 195

in focus

imagePenetration enhancers and mucoadhesives in liquid nasal spray formulations
Some commercially available liquid nasal spray formulations include excipients that can act as penetration enhancers or mucoadhesives. They may thereby provide the benefit of increasing contact/residence time in the nasal cavity or increasing absorption of drug molecules by enhancing permeability through nasal mucosal membranes. As liquid nasal sprays are now being developed to expand their use from traditional small molecule drug delivery systems to delivery of biologics and as a prophylaxis for respiratory diseases (including coronavirus treatments), the inclusion of penetration enhancers and mucoadhesives may become more important. The content of this October magazine article may assist readers in considering the utility of various penetration enhancers and mucoadhesives for use in research and development.


imagePropellant and formulation properties for next-generation pMDIs: Measurement, representation and prediction
The need for accurate thermophysical property prediction for diverse formulation mixtures is expected to grow, as next-generation formulations with low global warming potential (GWP) are introduced and as usage of predictive simulation increases during pMDI development. This need can be supported by appropriate experimental measurement campaigns for formulation mixtures, spanning the full range of temperature, pressure and composition that will be encountered by pMDI internal flows and aerosols. This October magazine article discusses a promising set of methods for representing and predicting many of these mixture thermophysical properties. This framework of physically-based models uses activity coefficients to describe non-ideal molecular interactions in the liquid phase, which can affect such properties.

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imageInformation on upcoming industry events
Click for information on the following industry events:
  • DDL2021
Please visit the calendar on Inhalation's website for more conferences, which may change from live to virtual formats and have new dates due to COVID-19.
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