Novel system to investigate the effects of inhaled volume and rates of rise in simulated inspiratory air flow on fine particle output from a dry powder inhaler
Journal Title: The AAPS Journal - Year 2002, Vol 4, Issue 2
Abstract
This study evaluated the effect of inhaled volume and simulated inspiratory flow rate ramps on fine particle output from dry powder inhalers (DPIs). A simple, robust system was developed to account for “rate of rise” (ramp) effects while maintaining a constant air flow through a multi-stage liquid impinger (MSLI), used for sizing the emitted particles. Ramps were programmed to reach 30 and 60 L/min over 100 milliseconds; 500 milliseconds; and 1, 2, and 3 seconds. Rotahaler was chosen as the test DPI. Testing was done with simulated inhalation volumes of 2 L and 4 L. Testing was also carried out using the USP apparatus 4. At 30 L/min, for a 2 L volume, the amount of drug exiting the device in fine particle fraction (FPF) increased from 2.33 μg to 6.04 μg from the 3-second ramp to the 100-millisecond ramp, with 11.64 μg in FPF for the USP (no ramp) method. At the same flow rate, for a 4 L volume, FPF increased from 2.23 μg to 8.45 μg, with 10.25 μg for the USP method. At 60 L/min, similar trends were observed. In general, at both flow rates, an increase in FPF was noted going from the shallowest to the steepest ramp. However, there were no significant differences in FPF when a 2 L inhaled volume was compared with a 4 L volume at each flow rate. Overall, these data suggest that the existing USP apparatus may overestimate FPF at flow rates lower than those recommended by the USP.
Authors and Affiliations
Varsha Chavan, Richard Dalby
Keywords
Related Articles
- EP ID EP681996
- DOI 10.1208/ps040211
- Views 80
- Downloads 0
Erratum to: Pharmacokinetic and Pharmacodynamic Analysis of Hyperthermic Intraperitoneal Oxaliplatin-Induced Neutropenia in Subjects with Peritoneal Carcinomatosis
The online version of the original article can be found at http://dx.doi.org/10.1208/s12248-010-9249-2.
Online Monitoring of PLGA Microparticles Formation Using Lasentec Focused Beam Reflectance (FBRM) and Particle Video Microscope (PVM)
Knowledge of the effects of different product and process variability on microparticle characterization is essential for the successful development, optimization, and scale-up of an encapsulation process. In the current...
Reproductible production of a PEGylated dual-acting peptide for diabetes
A pEGylated glucagon-like peptide-1 (GLP-1) agonist and glucagon antagonist hybrid peptide was engineered as a potential treatment for type 2 diabetes. To support preclinical development of this PEGylated dual-acting pep...
Role of morphine's metabolites in analgesia: Concepts and controversies
The metabolites of morphine, morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G), have been extensively studied for their contribution to clinical effects following administration of morphine. Those contributio...
Nonviral Gene Delivery: Principle, Limitations, and Recent Progress
Gene therapy is becoming a promising therapeutic modality for the treatment of genetic and acquired disorders. Nonviral approaches as alternative gene transfer vehicles to the popular viral vectors have received signific...