Martin Rowland1,2, Alessandro Cavecchi3,4, Frank Thielmann3, Janusz Kulon5, Jag Shur6, Robert Price6. 1. Pharmaceutical Surface Science Research Group, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY, UK. Martin.Rowland@pfizer.com. 2. Pfizer Ltd, Discovery Park House, Sandwich, Kent, CT13 9NJ, UK. Martin.Rowland@pfizer.com. 3. Novartis Pharma AG, Forum 1, Novartis Campus, 4056, Basel, CH, Switzerland. 4. Chiesi Farmaceutici S.p.A, Via Palermo, 26 A, 43122, Parma, Italy. 5. Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd, CF37 1DL, UK. 6. Pharmaceutical Surface Science Research Group, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY, UK.
Abstract
PURPOSE: To measure the charge to mass (Q/M) ratios of the impactor stage masses (ISM) from commercial Flixotide™ 250 μg Evohaler, containing fluticasone propionate (FP), Serevent™ 25 μg Evohaler, containing salmeterol xinafoate (SX), and a combination Seretide™ 250/25 μg (FP/SX) Evohaler metered dose inhalers (MDIs). Measurements were performed with a purpose built bipolar charge measurement apparatus (bp-NGI) based on an electrostatic precipitator, which was directly connected below Stage 2 of a Next Generation Impactor (NGI). METHODS: Five successive shots of the respective MDIs were actuated through the bp-NGI. The whole ISM doses were electrostatically precipitated to determine their negative, positive and net Q/m ratios. RESULTS: The ISM doses collected in the bp-NGI were shown to be equivalent to those collected in a standard NGI. FP particles, actuated from Flixotide™ and Seretide™ MDIs, exhibited greater quantities of negatively charged particles than positive. However, the Q/m ratios of the positively charged particles were greater in magnitude. SX particles from Serevent™ exhibited a greater quantity of positively charged particles whereas SX aerosol particles from Seretide™ exhibited a greater quantity of negatively charged particles. The Q/m ratio of the negatively charged SX particles in Serevent™ was greater in magnitude than the positively charged particles. CONCLUSIONS: The bp-NGI was used to quantify the bipolar Q/m ratios of aerosol particles collected from the ISMs of commercial MDI products. The positive charge recorded for each of the three MDIs may have been enhanced by the presence of charged ice crystals formed from the propellant during the aerosolisation process.
PURPOSE: To measure the charge to mass (Q/M) ratios of the impactor stage masses (ISM) from commercial Flixotide™ 250 μg Evohaler, containing fluticasone propionate (FP), Serevent™ 25 μg Evohaler, containing salmeterol xinafoate (SX), and a combination Seretide™ 250/25 μg (FP/SX) Evohaler metered dose inhalers (MDIs). Measurements were performed with a purpose built bipolar charge measurement apparatus (bp-NGI) based on an electrostatic precipitator, which was directly connected below Stage 2 of a Next Generation Impactor (NGI). METHODS: Five successive shots of the respective MDIs were actuated through the bp-NGI. The whole ISM doses were electrostatically precipitated to determine their negative, positive and net Q/m ratios. RESULTS: The ISM doses collected in the bp-NGI were shown to be equivalent to those collected in a standard NGI. FP particles, actuated from Flixotide™ and Seretide™ MDIs, exhibited greater quantities of negatively charged particles than positive. However, the Q/m ratios of the positively charged particles were greater in magnitude. SX particles from Serevent™ exhibited a greater quantity of positively charged particles whereas SX aerosol particles from Seretide™ exhibited a greater quantity of negatively charged particles. The Q/m ratio of the negatively charged SX particles in Serevent™ was greater in magnitude than the positively charged particles. CONCLUSIONS: The bp-NGI was used to quantify the bipolar Q/m ratios of aerosol particles collected from the ISMs of commercial MDI products. The positive charge recorded for each of the three MDIs may have been enhanced by the presence of charged ice crystals formed from the propellant during the aerosolisation process.
Authors: Virgil A Marple; Daryl L Roberts; Francisco J Romay; Nicholas C Miller; Keith G Truman; Michiel Van Oort; Bo Olsson; Michael J Holroyd; Jolyon P Mitchell; Dieter Hochrainer Journal: J Aerosol Med Date: 2003
Authors: Jennifer Wong; Yu-Wei Lin; Philip Chi Lip Kwok; Ville Niemelä; John Crapper; Hak-Kim Chan Journal: Mol Pharm Date: 2015-08-14 Impact factor: 4.939