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Η χορήγηση φαρμάκων μέσω της αναπνευστικής οδού αποτελεί τον πιο αποτελεσματικό τρόπο αντιμετώπισης νόσων του αναπνευστικού συστήματος όπως το άσθμα. Τα τελευταία χρόνια, η αύξηση στη συχνότητα εμφάνισης του άσθματος δημιούργησε την ανάγκη βελτίωσης της θεραπείας με το σχεδιασμό νέων συσκευών εισπνοής και την ανάπτυξη καλύτερης μορφοποίησης των φαρμάκων ώστε να εξασφαλίζεται ικανοποιητική κατανομή τους στο αναπνευστικό δένδρο. Στην παρούσα μελέτη, λαμβάνοντας υπόψη τις δυσκολίες ανάπτυξης ενός φαρμάκου για εισπνεόμενη χορήγηση, αποφασίσαμε να ασχοληθούμε με τη μορφοποίηση της φουμαρικής φορμοτερόλης, ενός ευρέως χρησιμοποιούμενου βρογχοδιασταλτικού φαρμάκου στη θεραπεία του βρογχικού άσθματος. Στόχος είναι η ανάπτυξη της βέλτιστης μορφοποίησης με την οποία θα επιτυγχάνεται το μέγιστο θεραπευτικό κλάσμα FPD. Διερευνήθηκε η επίδραση διαφόρων παραγόντων στη μεταφορά και εναπόθεση των λεπτόκοκκων σωματιδίων της φουμαρικής φορμοτερόλης στο αναπνευστικό δένδρο. Συγκεκριμένα, μελετήθηκε η επίδραση της κατανομής μεγέθους των σωματιδίων της λακτόζης στη μορφοποίηση και προσδιορίστηκε η κατανομή που επιτρέπει ικανοποιητική προσκόλληση της φουμαρικής φορμοτερόλης στη λακτόζη αλλά και εύκολο διαχωρισμό της απ’ αυτήν κατά την εισπνοή. Στη συνέχεια, διεξήχθησαν πειράματα προσδιορισμού του ιδανικού χρόνου ανάμιξης και των συνθηκών παραγωγής που εξασφαλίζουν ικανοποιητική ροή των κόνεων και πλήρωση των κυαθίων και δεν επηρεάζουν τη χημική σταθερότητα του φαρμάκου. Ακολούθησαν πειράματα για την αξιολόγηση της επίδρασης της μεταβολής στο βάρος πλήρωσης του κυαθίου στη μορφοποίηση και κατ’ επέκταση στο θεραπευτικό κλάσμα FPD. Τέλος, η μελέτη ολοκληρώθηκε μ’ ένα πείραμα ελέγχου της επίδρασης των εργαστηριακών συνθηκών στο Andersen Cascade Impactor και συνεπώς στη σταθερότητα του προϊόντος αλλά και την ικανότητα διασποράς του. / Drug delivery through the respiratory tract constitutes the most effective way of treating respiratory diseases such as asthma. Over the last years, the increased frequency of asthma occurrence challenged the improvement of therapy with the design of new inhalers and a better formulation development of drugs so as to achieve effective drug distribution to the respiratory tree. In the current study, having taken into consideration the difficulties of drug development for inhalation delivery, we have decided to work on the formulation of formoterol fumarate, a bronchodilator broadly used to the treatment of bronchial asthma. The aim is the optimization of formulation development so as to achieve the optimum therapeutic fraction FPD. The main idea was the examination of the effect of certain parameters on the delivery and deposition of formoterol fumarate fine particles to the respiratory tree. Specifically, the effect of lactose size distribution on the formulation was studied and the size distribution that allows not only effective adherence of formoterol fumarate to lactose but also efficient release during inhalation was determined. As a next step, experiments were carried out for the determination of the ideal mixing time and manufacturing conditions for satisfactory powder flowability, blister filling and chemical stability of drug. Experiments for the evaluation of the effect of blister filling variation on the formulation and consequently on the therapeutic fraction FPD followed. Finally, this study was completed by controlling the effect of laboratory conditions on the Andersen Cascade Impactor and consequently on the product stability and its dispersion ability.

Spray Polyurethane Foam insulation (SPF) kits are currently being marketed and sold to do-it-yourselfers to meet various insulating needs. Like commercial SPF systems, the primary health concern with SPF kits is user overexposure to the isocyanates during product application. The potential health risk associated with SPF applications is driven by several factors including (but not limited to): the toxicity of isocyanates; the potentially high exposure intensity; the quantity of isocyanates used in the process; the enclosed nature of the environment in which the product could be applied; the potentially high exposure duration/frequency; and the limited availability of control measures to reduce agent intensity (e.g., personal protective equipment, dilution ventilation). To better understand the potential hazards associated with the use of SPF kits, the current study was designed to provide an initial characterization of user exposure to airborne particulate during the application process. Specifically, the study would aim to answer the following: * What is the particle size distribution of the aerosol a SPF kit user is exposed to during application? * What is the airborne particle mass concentration a SPF kit user is exposed to during application? To answer these questions, a single commercially available SPF kit was selected for use and a mock residential environment was constructed to support repeated applications of SPF. Size-selective and total dust air sampling were conducted during the applications to determine the particle size distribution and mass concentration of aerosols generated by the selected kit. The particle size distributions developed from the size selective sampling results showed the presence of airborne particulate capable of penetration to the gas exchange regions of the respiratory tract. The average mass median diameter and geometric standard deviation of the particle size distributions were 4.6 µm and 2.7 respectively. The total dust sampling results showed mean airborne concentrations of 10.40 mg/m3. Based on the sampling results the study, personal air monitoring is needed to assess the degree of user exposure to methylene diphenyl diisocyanate (MDI) and to provide information for the selection of exposure control methods.

Today, orally inhaled drugs found on the market suffer from variable and discontinuous pulmonary drug release which lowers efficacy and patience compliance. This is usually a consequence of the poor understanding of the interaction and dissolution behavior of drug particles in the lung environment. Thus, the aim of this project was to investigate the effect of the dissolution medium on dissolution profiles for the well-known orally inhaled drug budesonide (BD) and fluticasone propionate (FP), in order to assess the importance of a proper selection of dissolution media for in vitro dissolution methods. In order to achieve this a modified Andersen Cascade Impactor was used to simulate deposition of particles onto filters. The dissolution was measured using a Transwell set up with polycarbonate membranes that can hold the filters with the deposited drug on it. Different media were prepared, from simple to more biorelevant. The samples taken during the dissolution experiments were analyzed quantitatively using UPLC-UV and the experimental data was processed by fitting to the Weibull function. The aim of this project was successfully achieved and the dissolution media that worked best for both BD and FP was PBS with the addition of 0.5% SDS. On the other hand, the dissolution media that performed the least for both BD and FP was the simulated lung fluid (SLF) with presence of 0.02% (w/v) DPPC. This may be due to the fact that DPPC forms liposomal aggregates which probably results in the media becoming more viscous and hence the dissolution time becomes slower.

The design and performance evaluation of in-duct, isokinetic samplers capable of testing flat sheet, nuclear-grade High Efficiency Particulate Air (HEPA) filters simultaneously with a radial filter testing system is discussed in this study. Evaluations within this study utilize challenge aerosols of varying particle diameters and masses such as hydrated alumina, Arizona test dust, and flame-generated acetylene soot. Accumulated mass and pressure drop for each in-duct sampler is correlated to the full-scale radial filter accumulated mass from initial to 10 in w. c. of loading. SEM imaging of samples at 25%, 50%, 75% and 100% loading verifies particle sizes with instrumentation used, revealing filter clogging resulting from particle impaction and interception. The U.S Department of Energy requires prototype nuclear-grade HEPA filters to be qualified under ASME AG-1 standards. The data obtained can be used to determine baseline performance characteristics on pleated radial filter medium for increased loading integrity and lifecycle endurance.

This thesis is based around examination of three mainstream inhaled drugs Formoterol, Budesonide and Beclomethasone for treatment of asthma and COPD. The areas investigated are these which have been raised in reports and studies, where there are concern, for drug use and assessment of their use. In reporting this work the literature study sets out a brief summary of the background and anatomy and physiology of the respiratory system and then discuses the mechanism of drug deposition in the lung, as well as the methods of studying deposition and pulmonary delivery devices. This section includes the basis of asthma and COPD and its treatment. In addition, a short section is presented on the role of the pharmacist in improving asthma and COPD patient's care. Therefore the thesis is divided into 3 parts based around formoterol, budesonide and beclomethasone. In the first case the research determines the in-vitro performance of formoterol and budesonide in combination therapy. In the initial stage a new rapid, robust and sensitive HPLC method was developed and validated for the simultaneous assay of formoterol and the two epimers of budesonide which are pharmacologically active. In the second section, the purpose was to evaluate the aerodynamic characteristics for a combination of formoterol and the two epimers of budesonide at inhalation flow rates of 28.3 and 60 L/min. The aerodynamic characteristics of the emitted dose were measured by an Anderson cascade impactor (ACI) and the next generation cascade impactor (NGI). In all aerodynamic characterisations, the differences between flow rates 28.3 and 60 were statistically significant in formoterol, budesonide R and budesonide S, while the differences between ACI and NGI at 60 were not statistically significant. Spacers are commonly used especially for paediatric and elderly patients. However, there is considerable discussion about their use and operation. In addition, the introduction of the HFAs propellants has led to many changes in the drug formulation characteristics. The purpose of the last section is to examine t h e performance of different types of spacers with different beclomethasone pMDIs. Also, it was to examine the hypothesis of whether the result of a specific spacer with a given drug/ brand name can be extrapolated to other pMDIs or brand names for the same drug. The results show that there are different effects on aerodynamic characterisation and there are significant differences in the amount of drug available for inhalation when different spacers are used as inhalation aids. Thus, the study shows that the result from experiments with a combination of a spacer and a device cannot be extrapolated to other combination.

Drywall, a popular building material made of gypsum based plaster sandwiched between two thick sheets of paper is used for building interior walls, is speedier alternative to traditional plaster, decreasing time and labor for construction. Importance of drywall increased with the demand for drywall after nine hurricanes hit Florida in 2004-05 and widespread damage caused in the Gulf Coast after Katrina in 2005. This study has two parts. First part presents an analysis of metals like strontium for the identification of Chinese drywall, and a comparison of strontium concentrations of American drywall and Chinese drywall using XRF (X-Ray Fluorescence) analysis with the Innov-X XRF analyzer. The second part presents an analysis of metal exposure during cutting and installation of drywall using 8stage Cascade impactor. The work space concentration of, different metals is analyzed using XRF analysis and particulate matter within various size ranges, were calculated and their effects are studied.

Advancements in pulmonary drug delivery technologies have improved the use of dry powder inhalation therapy to treat respiratory and systemic diseases. Despite remarkable improvements in the development of dry powder inhaler devices (DPIs) and formulations in the last few years, an optimized DPI system has yet to be developed. In this work, we hypothesize that Thin Film Freezing (TFF) is a suitable technology to improve inhalation therapies to treat lung and systemic malignancies due to its ability to produce brittle powder with optimal aerodynamic properties. Also, we developed a performance verification test (PVT) for the Next Generation Cascade Impactor (NGI), which is one of the most important in vitro characterization methods to test inhalation. In the first study, we used TFF technology to produce amorphous and brittle particles of rapamycin, and compared the in vivo behavior by the pharmacokinetic profiles, to its crystalline counterpart when delivered to the lungs of rats via inhalation. It was found that TFF rapamycin presented higher in vivo systemic bioavailability than the crystalline formulation. Subsequently, we investigated the use of TFF technology to produce triple fixed dose therapy using formoterol fumarate, tiotropium bromide and budesonide as therapeutic drugs. We investigated applications of this technology to powder properties and in vitro aerosol performance with respect to single and combination therapy. As a result, the brittle TFF powders presented superior properties than the physical mixture of micronized crystalline powders, such as excellent particle distribution homogeneity after in vitro aerosolization. Lastly, we developed a PVT for the NGI that may be applicable to other cascade impactors, by investigating the use of a standardized pressurized metered dose inhaler (pMDI) with the NGI. Two standardized formulations were developed. Formulations were analyzed for repeatability and robustness, and found not to demonstrate significant differences in plate deposition using a single NGI apparatus. Variable conditions were introduced to the NGI to mimic operator and equipment failure. Introduction of the variable conditions to the NGI was found to significantly adjust the deposition patterns of the standardized formulations, suggesting that their use as a PVT could be useful and that further investigation is warranted. / text

Cette thèse se consacre à la mise au point de techniques d’échantillonnage suivies d’analyses réalisées au laboratoire pour mettre en évidence les espèces majoritaires en air intérieur et caractériser leurs variations temporelles. Le développement analytique a été effectué pour 52 COVs et pour 16 HAPs associés à la phase particulaire de l’air. Les prélèvements des COVs ont été réalisés au moyen d’un préleveur automatique permettant d’échantillonner l’air sur des tubes extraits par désorption thermique et analysés par chromatographie gazeuse couplée à la détection FID. Pour la quantification des HAPs, le prélèvement des particules est effectué par un impacteur à cascade à trois étages permettant de fractionner l’aérosol en fonction de leur diamètre aérodynamique. Les HAPs sont quantifiés par chromatographie liquide haute performance couplée à la détection par fluorescence. Ces deux techniques ont été mises en application dans le cadre de la 1ère campagne intensive du projet MERMAID. / This work aims at developing rapid and simple air sampling techniques followed by laboratory analyses to highlight the occurrence of the main species in indoor air and to describe their temporal variations. The analytical development was focused on 52 VOCs belonging to a wide variety of chemical families to determine their concentrations. The sampling step was performed using an automatic sampler allowing the sampling of air on adsorbent tubes. These tubes were then thermally desorbed and analyzed by gas chromatography coupled to FID. Another analytical development was conducted to determine the particle bound PAHs concentrations. The sampling of particles was realized by the mean of a 3-stages cascade impactor allowing an aerosol fractionation depending on their aerodynamic diameter. Finally, quantification of PAHs was realized by liquid chromatography coupled to fluorescence detection. These two techniques were applied in a field campaign in the frame of the MERMAID program.

An issue of inhalation therapy is a complex topic, actively discussed in last decades, and its progress in various scientific fields is more than required. First part of this thesis brings a theoretical introduction into principles of aerosol therapy and into the requirements resulting from them. Commonly available technologies of inhalers and nebulisers for medical usage, parameters that determinate their effectivity are briefly described. Usage mistakes influencing the effectivity of inhalation are discussed, as well. Second part deals with experimental measurements of aerosol that selected inhalers generate. It also describes difficulties connected with the methods of these measurements, with sampling and following analyses. Gained results are compared with an available literature.