Pressurized aerosol

The word propellant is also used for the liquefied gas in a pressurized aerosol container. 

Newman, S.P., Clark, A.R., Talaee, N., and Clarke, S.W., Pressurized aerosol deposition in the human lung with and without an open spacer device. Thorax, 44 706-710 (1989). Newman, S.P., Clark, A.R., Talaee, N., and Clarke, S.W., Lung deposition of 5 mg Intal from a pressurized metered dose inhaler assessed by radiotracer technique, Int. J. Pharm., 74 203-208 (1991). 

Fuller, H.D., Dolovich, M.B., Posmituck, G., Wong, Pack, W., and Newhouse, M.T., Pressurized aerosol versus jet aerosol delivery to mechanically ventilated patients. Am. Rev. Resp. Dis., 142 440-444 (1990). 

Schreiner, J., C. Voigt, K. Mauersberger, P. McMurry, and P. Zie-mann, Aerodynamic Lens System for Producing Particle Beams at Stratospheric Pressures, Aerosol Sci. Technol., 29, 50-56 (1998). 

Dalby RN, Byron PR. Comparison of output particle size distributions from pressurized aerosols formulated as solutions or suspensions. Phann Res 1988 5(1) 36—39. 

Local adverse effects are common in patients with asthma who use inhaled glucocorticoids, as suggested by a survey of the prevalence of throat and voice symptoms in patients with asthma using glucocorticoids by metered-dose pressurized aerosol (SEDA-20, 369 35). 

Williamson IJ, Matusiewicz SP, Brown PH, Greening AP, Crompton GK. Frequency of voice problems and cough in patients using pressurized aerosol inhaled steroid prepara- 53. tions. Eur Respir J 1995 8(4) 590-2. 

Evans, R. M., and S. J. Farr. 1992. The development of novel, pressurized aerosols formulated as solutions J. Biopharm. Sci3 33-40. 

B. J. Lipworth, and D. J. Clark, Lung delivery of salbutamol given by breath activated pressurized aerosol and dry powder inhaler devices, Pulm. Pharmacol. Ther. 70 211 (1997). 

S. Cohen, Quantitative determination of volatile components in pressurized aerosols by gas chromtography, J. Pharm. Sci., 57 966 (1968). 

To test a chemical contained in a pressurized aerosol container, the eye should be held open and the test chemical administered in a single burst of about 1 second from a distance of 10 cm directly in front of the eye. The dose may be estimated by weighing the container before and after use. Care should be taken not to damage the eye. Pump sprays should not be used but instead, the liquid should be expelled and 0.1 mL collected and instillated into the eye as described for liquids. 

A number of topical products marketed as a pressurized aerosol may be dispensed in a metallic bottle with a screw cap. Topical dosage forms in aluminum tubes usually include a liner. A tube liner is frequently a lacquer or shellac whose composition should be stated. A metallic pressurized packaging system for a liquid-... 

The type of nasal device employed in delivering a drug formulation plays a major role in the efficacy of the treatment. In general, two types of delivery systems are used mechanical pumps and pressurized aerosol containers. The properties of the drug to be used influence the selection of the system. The various types of delivery devices are described in the following sections. 

Newman, S.P. Metered-dose pressurized aerosols and the ozone layer. Eur. Resp. J. 1990, 3, 495-491. 

Newman, S.P. Clark, A.R. Talaee, N. Clark, S.W. Pressurized aerosol deposition in the human lung with and without an open spacer device. Thorax 1989, 44, 706-710. 

A mathematical model of a nanoparticles growth during evaporation of a micron size droplet in a low pressure aerosol reactor is developed. The main factor is found to be evaporating cooling of droplets which affects formation of supersaturated solution in the droplet. The rate of cooling can reach 2T0 K/s. The final radius of nanoparticles was found to be independent on the precursor radius. Manifestation of Lifshitz-Slezov instability is illustrated by experimental data. Effects of Brownian motion of nanoparticles inside the droplet are discussed. 

Recently it was experimentally proven that the highest yield of nanoparticles of different substances, including semiconductor and magnetic ones, is obtained in low pressure spray pyrolysis of special multicomponent solutions [1], During this pyrolysis micron size droplets of the multicomponent aqueous solution evaporate in a low pressure aerosol reactor. Additionally these droplets often have solid precursors of nanometer size, so we can consider every droplet as a colloidal solution. 

Figure 1. Droplet tenperature vs the path length in a low pressure aerosol reactor. (1) The ammonia molar fraction x=0.33 in a droplet and Xg=0.05 in the gas mixture, (2) x=0.05 and Xg=0.26, (3)...

Formoterol is a long-acting selective beta2-adrenoceptor agonist that is more potent than salmeterol (1) and has a similar duration of action (12 hours) but a rapid onset of effect similar to that of salbutamol. It is available as a multidose, pressurized aerosol and as a dry powder inhaler, delivering 0.006 or 0.012 mg per dose. The usual dose is 0.012 mg bd. 

Formoterol 12 and 24 micrograms, delivered from either a multidose pressurized aerosol or a dry powder inhaler, did not affect heart rate. However, at doses of 48 and 96 micrograms the heart rate rose significantly after the dry powder formulation. Tremor was significantly higher after the 48 micrograms dose of dry powder compared with the multidose pressurized aerosol. The two formulations were equipotent in producing bronchodilatation (SEDA-21, 184). 

The multidose pressurized aerosols using chlorofluorocarbon propellants have been widely used. 

In animal experiments, plasma concentrations of Freon 11 and Freon 12 of 20-35 pg/ml sensitized the heart to adrenaline and exercise. Severely ill asthmatic subjects (mean oxygen tension=55mmHg, range 50-80) were studied following therapeutic doses of a beta2-adrenoceptor agonist pressurized aerosol. Plasma concentrations of... 

Dollery CT, Williams FM, Draffan GH, Wise G, Sahyoun H, Paterson JW, Walker SR. Arterial blood levels of fluorocarbons in asthmatic patients following use of pressurized aerosols. Clin Pharmacol Ther 1974 15(l) 59-66. 

Salmeterol is a selective beta2-adrenoceptor agonist that is more potent and has a significantly longer duration of action than salbutamol (SEDA-21, 184). It is used as a supplement to inhaled glucocorticoids for sustained bronchodUatation. It has a much slower onset of effect than salbutamol and is not effective in acute attacks of asthma. It is available as a multidose-pressurized aerosol 0.025 mg/puff, and as a dry powder, Diskhaler or Accuhaler 0.05 mg per dose. The adverse effects profile of salmeterol is the same as that of salbutamol and other betaz-agonists (SEDA-21, 185). 

Kono, H. O., Jordan, B, Ohtake, T. Duane, H, S. (1998) Formation and Measurement of the porosities, tensile strengths, and deformation coefficient of gasification filter cakes at operating temperatures and pressures. Aerosol Science and Technology v 29 p 236-245... 

Vapor pressure is used for estimating the volatility of chemical compounds and the environmental fate of chemicals. This coefficient is also important in pharmaceutical studies, for example, for development of perfumes and pressurized aerosols. 

Newman SP, Pavia D, Moren F, Sheahan NF. Deposition of pressurized aerosols in the human respiratory tract. Thorax 1981, 36, 52-55. 

Low-pressure aerosols which are self-contained, or handsprayers which can be refilled, are the most suitable products to use in relatively conhned spaces such as are found in domestic premises, offices and small stores. Windows and doors should be closed before treatment, fn retail outlets, small storage facilities and dairy bams (Wright, 1977), specially formulated aerosols can be dispensed from wall-mounted units which automatically discharge measured doses at regular intervals. Such devices can keep premises with volumes up to 170 m 1 (6U0U ft3) insect free fur 3 months. 

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