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Estimating Pure Component Vapor Pressures of Complex Organic Molecules
Modifications of the entropy of boiling term and heat capacity change upon boiling term are made to the Yalkowsky−Mishra vapor pressure equation. These modifications eliminate a systematic error and
A theoretical and experimental analysis of formulation and device parameters affecting solution MDI size distributions.
  • S. Stein, P. Myrdal
  • Chemistry, Medicine
    Journal of pharmaceutical sciences
  • 1 August 2004
Theoretical and empirical equations were developed that make it possible to predict the residual particle size distribution for solution MDIs.
Advances in Metered Dose Inhaler Technology: Formulation Development
This review presents a survey of challenges associated with formulating MDIs as solution or suspension products with one or more drugs, while considering the physicochemical properties of various excipients and how the addition of theseexcipients may impact overall product performance of the MDI.
Analysis of drug content and weight uniformity for half-tablets of 6 commonly split medications.
The drug content and weight in split half-tablets of 6 commonly split medications using drug assay analysis was determined to determine whether the drugs met proxy USP specification for %RSD (less than 6% for all drugs studied).
An Evaluation of Mass-Weighted Size Distribution Measurements with the Model 3320 Aerodynamic Particle Sizer
The ability of the Model 3320 aerodynamic particle sizer (APS) to make accurate mass-weighted size distribution measurements was investigated. Significant errors were observed in APS size
The Relative Influence of Atomization and Evaporation on Metered Dose Inhaler Drug Delivery Efficiency
Factors influencing the delivery efficiency from HFA-134a MDIs were examined theoretically and experimentally. The time required for evaporation of HFA-134a and ethanol droplets were theoretically
Evaluation of a new Aerodynamic Particle Sizer Spectrometer for size distribution measurements of solution metered dose inhalers.
The ability of the Model 3320 and newer Model 3321 Aerodynamic Particle Sizer Spectrometer (APS) to make accurate mass-weighted size distribution measurements of solution metered dose inhalers (MDIs) was evaluated and was shown to be proportional to drug concentration to the one-third power.
Advances in Metered Dose Inhaler Technology: Hardware Development
Improvements discussed in this article increase the ability of MDI systems to meet regulatory specifications and include discussion of enhancements made to the device’s core subsystems.
AQUAFAC 1: Aqueous functional group activity coefficients; application to hydrocarbons
Abstract A simple group-contribution method for the estimation of aqueous activity coefficients is introduced. The AQUAFAC method derives group values directly from aqueous data. This work shows the
A comparison of two methods to determine the solubility of compounds in aerosol propellants.
The two methods for determining the solubility of compounds in propellant based metered dose inhaler (MDI) formulations were found to be in good agreement with each other, with the new direct injection technique offering enhanced precision and accuracy along with considerable reduction in analysis time.