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Synthesis of Nanomaterials for Drug Delivery
Published in Vineet Kumar, Praveen Guleria, Nandita Dasgupta, Shivendu Ranjan, Functionalized Nanomaterials II, 2021
Hemant K. S. Yadav, Shahnaz Usman, Karyman Ahmed Fawzy Ghanem, Rayisa Beevi
The main components of a flame spray pyrolysis are: An atomizer – This assists in creating droplets from the liquid feed administered. There are mainly three types of atomizers which are ultrasonic nebulizer, two-fluid nozzle, and electro sprayer. An ultrasonic nebulizer uses high frequency vibrations to produce sprays and to convert liquid into mist. which then enters the flame. The two-fluid nozzle works by using an atomizing gas to disperse liquid into the spray. An electro sprayer forms an aerosol from liquid using a high voltage.Burner – This generates the flame required for the process.Collector – This is used to collect the final end product.[49]
Inductively Coupled Plasma Optical Emission Spectrometry
Published in Grinberg Nelu, Rodriguez Sonia, Ewing’s Analytical Instrumentation Handbook, Fourth Edition, 2019
In an ICP-OES, all samples are normally converted to liquid form first and then pumped by a peristaltic pump into the instrument. The liquid is converted into an aerosol or mist by a device named nebulizer. The nebulization process is one of the critical steps in ICP-OES. A perfect nebulizer should be able to convert all liquid samples into aerosol such that the plasma discharge could reproducibly desolvate, vaporize, atomize, ionize, and excite.
Inhalation Drug Products Containing Nanomaterials
Published in Anthony J. Hickey, Sandro R.P. da Rocha, Pharmaceutical Inhalation Aerosol Technology, 2019
Sandro R.P. da Rocha, Rodrigo S. Heyder, Elizabeth R. Bielski, Ailin Guo, Martina Steinmaurer, Joshua J. Reineke
Phase I and phase II clinical trials were conducted on patients with primary or metastatic lung cancer (Verschraegen et al. 2000, Verschraegen et al. 2004, Verschraegen 2006). The treatment strategy included nebulized L9NC from AeroMist nebulizer (CIS-US) at a flow rate of 10 L/min for 30 minutes and delivered twice daily for 5 consecutive days/week for 1 week, 2 weeks, 4 weeks, or 6 weeks followed by 2 weeks of rest at a dose of 6.7 µg/kg/day. Stepwise dose escalation was also used with doses ranging from 6.7 µg/kg/day to 26.6 µg/kg/day delivered Monday through Friday for 8 weeks followed by 2 weeks of rest (Verschraegen et al. 2004). It was concluded that aerosolized L9NC was safe to use with minimal side effects. Plasma levels of drug were seen to be comparable to those when drug is given orally, but with less side effects. An optimal dose was found to be 13.3 µg/kg/day (0.5 mg/m2/day) with two consecutive 30 minute nebulizations/day with a concentration of 4 mg/mL of 9NC given from Monday–Friday for 8 weeks with 2 weeks rest (total 10 weeks) (Verschraegen et al. 2004). Responses were observed in patients who had endometrial cancer within the lungs seeing partial remission as well as partial remissions in liver metastasis demonstrating potential of lung treatment as well as systemically (Verschraegen et al. 2004, Verschraegen 2006). There was a lack of hematologic toxicity as seen previously with oral administration (Verschraegen 2006). Phase II studies for non-small lung cancer and endometrial cancer were initiated, however, due to a small amount of patients, data were inconclusive to determine efficacy of treatment (Verschraegen 2006). In conclusion, L9NC demonstrated potential of liposomal inhaled therapeutics for treatment of lung cancers, metastatic cancers to the lung, and in some cases, cancer treatment to other sites as well. However, more robust and larger clinical trials need to be run to further address the efficacy of such treatment plans for patients.
Ozone treatment in a wind tunnel for the reduction of airborne viruses in swine buildings
Published in Aerosol Science and Technology, 2020
Jonathan M. Vyskocil, Nathalie Turgeon, Jean-Gabriel Turgeon, Caroline Duchaine
Phage amplification was performed as described in other studies (Verreault et al. 2010). Briefly, host strain E. coli (HER 1036) was incubated overnight at 37 °C with 200 rpm shaking. The following day, 50 μl of host was added to 50 ml TSB which was incubated (37 °C, 200 rpm) until the optical density reached 0.17. Phage PhiX174 (HER-036 obtained from the Félix d’Hérelle Reference Center for Bacterial Viruses) were added and incubation was pursued overnight (37 °C, 200 rpm). Incubation was followed by centrifugation (10 min at 7197 xg) and filtration (0.45 μm) to remove remaining host strain from phage lysate. A Collison 6-jet nebulizer (BGI Instrument Inc., Waltham, MA) was filled with 50 ml of phage buffer (20 mM Tris-HCl, 100 mM NaCl, 10 mM MgSO4, pH 7.5) containing 1 ml of phage lysate (106 or 107 PFU/ml). The first two sampling days used a lysate with a concentration of 106 PFU/ml while the remainder were 107 PFU/ml. Aerosolized phages were passed through a diffusion dryer (model 3062, TSI Inc., Shoreview, MN, USA) before being injected into the tunnel 50 cm before the ozone injection probe. Compressed air (20 psi) was supplied to the nebulizer through a filter system (TSI Inc., model 3074). Prior to sampling, the Collison nebulized phages for 10 min to allow for equalization throughout the system.
Determination of the content of metals in used lubricating oils using AAS
Published in Petroleum Science and Technology, 2019
Artur Wolak, Grzegorz Zając, Wojciech Gołębiowski
The atomic absorption spectrometry method (AAS) was applied to determine the selected chemical elements in the used engine oil. The source of the radiation is a halogen cathode lamp (HCL). One lamp allows only one element to be examined. Flame atomization requires a liquid analytical sample to be aerosolized. The aerosol is obtained in a pneumatic nebulizer. In the nebulizer chamber, the analyzed solution is converted into a fine mist (aerosol), then the aerosol is mixed with the flammable gas, and introduced uniformly into the burner using spray surfaces. The suction gas is always an oxidizing gas. The flames of the burner must provide enough energy to convert the solution into free atoms. The flame itself should only absorb a small fraction of the radiation emitted by the source. An acetylene-air flame was used to determine the following elements: Mg, Fe, Ni, Cu, Zn and Pb. It has a high temperature and only below 230 nm an increasing self-absorption of the flame may be observed. For other elements (Ca, Cr and Al) that form persistent oxides in the flame, it was necessary to use a reducing flame with nitrogen oxide (I) oxide gas.
A review of microfluidic concepts and applications for atmospheric aerosol science
Published in Aerosol Science and Technology, 2018
Andrew R. Metcalf, Shweta Narayan, Cari S. Dutcher
Aerosol science can also tap into the benefits of using a microfluidic platform. Biphasic (droplet) microfluidics can be used to (1) study interfacial phenomena of aerosol chemical mimics using droplets (liquid–liquid interface) or bubbles (liquid–air interface) and (2) encapsulate an aerosol particle in one phase (e.g., an aqueous phase for dissolution of water-soluble species) for transport by an immiscible, carrier phase. Once in the device, rapid sorting, manipulation, and measurements are possible with a variety of geometries. Already, recent studies have begun to use microfluidics for measurements of interfacial tension to characterize chemical mimics of atmospheric aerosol (Metcalf et al. 2016; Boyer and Dutcher 2017) and for detection of bioaerosol hazards (Damit 2017). In recent development of low-cost sensors, microfluidic and micro electromechanical systems (MEMS) devices have seen increasing application, such as the air-microfluidics based PM 2.5 sensor that can be used for affordable personal monitoring of hazards such as tobacco smoke or diesel exhaust (Paprotny et al. 2013). In addition, a microfluidic nebulizer could improve the monodispersity of aerosol populations for calibration of traditional aerosol sampling instruments (Amstad et al. 2017).