Les résidus pharmaceutiques sont considérés comme un problème écologique émergent, à cause de leur présence et leur accumulation continue dans l’environnement. Même à des faibles concentrations, ces substances sont susceptibles de menacer l’ensemble des organismes vivants. Il est donc, urgent de développer les moyens techniques permettant leur élimination. Dans ce cadre s’inscrit le travail de cette thèse, il a pour objectif de traiter la carbamazépine, un antiépileptique largement détecté dans le milieu aquatique. Une première étude a été menée sur la biodégradation de la carbamazépine par des boues activées par biostimulation avec différentes sources de carbone conventionnelles. Une optimisation des différents paramètres opératoires a été également effectuée. En outre, une seconde étude a porté sur la biodégradation de la molécule cible par une souche fongique, et ce travail a été achevé par une troisième étude de synthèse mettant en place la technique de bioaugmentation fongique des boues activées afin d’améliorer la performance du traitement. / Pharmaceutical residues are considered an emerging environmental problem because of their presence and their continuous accumulation in the environment. Even at low concentrations, these substances may threaten all living organisms. It is therefore urgent to develop the technical means to eliminate them. In this framework is the work of this thesis, it intended to treat carbamazepine, an antiepileptic drug widely detected in the aquatic environment. A first study was conducted on the biodegradation of carbamazepine by activated sludge by biostimulation with various sources of conventional carbon. An optimization of the various operating parameters was also performed. In addition, a second study examined the biodegradation of the target molecule by a fungal strain, and this work was completed by a third synthesis study establishing technical fungal bioaugmentation of activated sludge to improve performance treatment.

In this study, the ability of pharmaceutical cocrystals on improving solubility and dissolution behaviour of poorly water soluble drug has been studied by a novel technique SDI300 UV imaging surface dissolution system. Pharmaceutical cocrystals of poorly water soluble drug carbamazepine (CBZ) were synthesized, which are 1: 1 carbamazepine - nicotinamide (CBZ-NIC) cocrystal, and 2:1 carbamazepine - succinic acid (CBZ-SUC) cocrystal. Firstly, dissolution and solution mediated phase transformation behaviour (SMPT) of CBZ-NIC cocrystal was studied by in situ techniques of UV imaging and Raman spectroscopy. This study has shown that in situ UV imaging and Raman spectroscopy with a complementary technique of SEM can provide an in depth understanding of cocrystal dissolution processes. It has been found that CBZ-NIC cocrystal including other polymorphs of CBZ III and I and mixture are converting to CBZ DH during dissolution. The influence of surfactants, SLS and Tween 80, on the solubility and dissolution behavior of the CBZ-NIC cocrystal has been studied. Results show that the SMPT of CBZ III and CBZ-NIC cocrystal can be altered by inclusion of a surfactant in dissolution medium. However, CBZ III and CBZ-NIC cocrystal have shown different transformation behavior with different surfactants. The solubility and dissolution behaviour of CBZ-NIC cocrystal, CBZ-SUC cocrystal in four biomedia (simulated gastric fluid, pH1.2 HCl buffer, simulated intestinal fluid, and pH 6.8 PBS buffer) were studied. Results have shown that equilibrium solubility of CBZ samples varied in different media. The two cocrystals dissolution rates show different trends as that of parent drug CBZ III. This can be explained by that the formation of cocrystal change the dissolution ability of CBZ III.

L'eau est vitale pour l'existence de tous les organismes vivants, mais cette ressource précieuse est de plus en en plus menacée et polluée à cause de l’augmentation de la demande en eau potable qui résulte à la fois de l’accroissement de la population mondiale mais aussi de l’activité économique tant au niveau de l’agriculture que de l’industrie. La préservation de cette ressource est aujourd'hui l'une des premières préoccupations de la recherche dans le domaine du traitement des eaux. Dans ce travail, l’élimination de deux polluants typiques des activités humaines, les nitrates et la carbamazépine, est étudiée au moyen de méthodes de traitements électrochimiques et biologiques non-conventionnelles. Le travail se concentre d'une part sur l'électrocoagulation (EC) qui associe les avantages d'être non-spécifique et de combiner plusieurs mécanismes de dépollution simultanés (adsorption, électro-oxydation ...); d’autre part, un traitement biologique innovant de faible coût utilisant une algue verte, Ankistrodesmus braunii, a été développé. Enfin, les avantages, limitations et perspectives de ces deux procédés sont comparés à ce qui existe dans la littérature et sont discutés. / Water is vital to the existence of all living organisms, but this valued resource is increasingly being threatened and polluted as human populations and activities grow and demand more water of high quality for domestic purposes and economic activities. Wastewater treatment for resource preservation is nowadays one of the first concerns of research in this field of science. In this work, two typical pollutants from agriculture and domestic activity, Nitrates and Carbamazepine, are quantitatively addressed by non-conventional electrochemical and biological treatment methods. The study focuses, on the one side, on electrocoagulation (EC) that exhibits the advantages to be non-specific and to combine various depollution mechanisms (adsorption, electro-oxidation...) that act simultaneously; on the other side, innovative and low-cost biological treatments using green algae, Ankistrodesmus braunii, are developed. Finally, the respective advantages, limitations and perspectives of these processes are compared to the literature and discussed.

Thesis ((M. Pharm. (Pharmaceutics)) -- University of Limpopo, 2019 / Epilepsy is the fourth most common neurological disorder after migraine, stroke and Alzheimer’s disease and it affects about fifty million people worldwide. Careful consideration should be taken when deciding to initiate treatment in epilepsy as it should consider the balance between the possibility of further seizures and their associated risks, including the possible risk of sudden expected death, inconvenience and the risks of taking regular medication for each individual. In the early 1980’s, the first-line treatment for epilepsy was polytherapy. This was due to findings that smaller doses of two drugs rather than larger doses of one drug can achieve synergistic effects or less drug toxicity. However, following more trials on the treatment of epilepsy, this was later changed to monotherapy as first-line treatment. Despite the change, patients remain uncontrolled on a single anti-epileptic drug, thus they are initiated on polytherapy, one such combination being carbamazepine in combination with sodium valproate. The use of these in combination has pharmacological threats such as compliance, the control of side effects and the achievement of synergistic effects. The development of a Fixed Dose Combination (FDC) has often been used to resolve pharmacological threats, and this study aims to develop a fixed dose combination tablet of carbamazepine and sodium valproate to resolve the pharmacological threats in epilepsy. Samples of carbamazepine and sodium valproate and a physical mixture (1:1 w/w) of both drugs and excipients were prepared for compatibility with thermal analysis and spectroscopy techniques. Data was analysed by comparing the DSC curves, FTIR spectra, XRPD peaks and TAM analysis of carbamazepine and sodium valproate alone and in their physical mixture (1:1 w/w) and with excipients. Both carbamazepine and sodium valproate were evaluated for flowability using angle of repose, tapped and bulk density, compressibility index and particle size distribution. To formulate the proposed FDC tablet of carbamazepine and sodium valproate, direct compression and wet granulation methods were employed. The tablets were then evaluated for official and non-official post formulation parameters (weight variation, crushing strength, friability, diameter and thickness, and disintegration) according to BP and USP standards. A standardised HPLC method was developed and validated for analytical procedures. Dissolution studies were conducted xiii according to USP methods to verify and quantify the release of the APIs from the FDC tablet. Carbamazepine and sodium valproate were tested for compatibility with excipients using DSC, FTIR, XRPD and TAM analysis. The overall results confirmed that carbamazepine and sodium valproate are compatible, with each other and the excipients used in the study. Powder flow of carbamazepine and sodium valproate was poor, hence they were subjected to granulation prior to compression to improve flowability. The specifications of the fixed-dose combination were developed in accordance with the FDA’s quality by design concept and WHO recommendations. The tablets were subjected to non-official and official pharmacopoeial tests, and passed all the tests. Dissolution studies according to a USP method were conducted to verify and quantify the release of the APIs in the fixed-dose combination. The initial dissolution rate (DRi) of carbamazepine and sodium valproate in the SLS dissolution medium was rapid as required for an immediate release formulation. The study aimed at developing a fixed dose combination of carbamazepine and sodium valproate to try to reduce the burden of taking more than one tablet for epilepsy. Based on the results obtained from preformulation studies to assay of the final product, the study was successful. / Chieta bursary and HWseta

The presence of pharmaceuticals and personal care products (PPCPs) in the aquatic environment has been a growing issue of concern over the past twenty years. Compounds from various pharmaceutical classes have been detected at ng to µg L-1 concentrations in waste water effluent, surface, ground and drinking water. Although the concentrations required for these compounds to elicit a therapeutic response is higher than what is detected in the aquatic environment, the impacts pharmaceuticals may have on aquatic species under chronic or mixture conditions remains largely unknown. This thesis addresses this knowledge gap by evaluating the impacts of chronic exposure to four frequently detected pharmaceuticals and pharmaceutical mixtures on the physiology of the model teleost, zebrafish (Danio rerio). Environmentally relevant concentrations of acetaminophen, carbamazepine, gemfibrozil and venlafaxine significantly reduced zebrafish fecundity and increased embryonic mortality. Pharmaceutical exposure to gemfibrozil and carbamazepine altered the structural morphology of the ovary; all compounds tested altered kidney histology. As exposure in the environment is rarely ever to a single compound, animals were exposed to a quaternary mixture of the four compounds and wastewater effluent. Under mixture conditions, reproductive, developmental and histological effects were also observed, however they generally were more severe then those seen with single compound exposure. Overall, these results showed that chronic, low dose pharmaceutical exposure were sufficient to induce a suite of physiological effects suggesting an overall decrease in fish health. Effects on offspring after chronic parental exposure to gemfibrozil and carbamazepine resulted in alterations in male breeding behaviour, reduced fecundity, decreased sperm velocity and induced morphological changes to spermatozoa. These novel findings expand the limited knowledge base of studies examining effects on offspring. Lastly, acetaminophen was confirmed to elicit its developmental impacts in fish via the cyclooxygenase pathway; the same mechanism of action as observed in mammals. This thesis has made significant contributions to identifying the physiological consequences of environmental pharmaceutical toxicity to fish. / Thesis / Candidate in Philosophy

yes / A transflectance near infra red (NIR) spectroscopy approach has been used to simultaneously measure drug and plasticiser content of polymer melts with varying opacity during hot melt extrusion. A high temperature reflectance NIR probe was mounted in the extruder die directly opposed to a highly reflective surface. Carbamazepine (CBZ) was used as a model drug, with polyvinyl pyrollidone-vinyl acetate co-polymer (PVP-VA) as a matrix and polyethylene glycol (PEG) as a plasticiser. The opacity of the molten extrudate varied from transparent at low CBZ loading to opaque at high CBZ loading. Particulate amorphous API and voids formed around these particles were found to cause the opacity. The extrusion process was monitored in real time using transflectance NIR; calibration and validation runs were performed using a wide range of drug and plasticiser loadings. Once calibrated, the technique was used to simultaneously track drug and plasticiser content during applied step changes in feedstock material. Rheological and thermal characterisations were used to help understand the morphology of extruded material. The study has shown that it is possible to use a single NIR spectroscopy technique to monitor opaque and transparent melts during HME, and to simultaneously monitor two distinct components within a formulation.

Although wastewater treatment plants are a line of defense in minimizing indiscriminate output of microconstituents to natural waters, we do not possess a fundamental understanding of the mechanisms involved in microconstituent removal during wastewater treatment. With this in mind, experiments were designed to investigate the factors that can influence the fate of four microconstituents, carbamazepine (CBZ), 17alpha-ethinylestradiol (EE2), iopromide (IOP), and trimethoprim (TMP), during biological suspended culture treatment. Specifically, the role that various ecological members of biological treatment systems play in biotransforming these compounds was evaluated. Sorption assays were performed with inactivated biomass samples (ammonia oxidizing bacteria (AOB), laboratory enriched heterotrophic cultures free of active nitrifiers with low (Ox⁻) or high (Ox⁺) oxygenase activity, and a nitrifying activated sludge (NAS) from a full-scale wastewater treatment plant) to determine whether partitioning dictates removal of individual microconstituents. No microconstituents sorbed to the AOB culture. Neither CBZ nor IOP sorbed to Ox⁻, Ox⁺ and NAS cultures; however, EE2 and TMP sorbed to the Ox⁻, Ox⁺ and NAS biomass. Sorption was positively influenced by the presence of exopolymeric substances (EPS) associated with the cultures. The protein content of EPS affected EE2 and TMP sorption more appreciably than the polysaccharide content of EPS. Further experiments were performed to investigate microconstituent biodegradation by AOBs, Ox⁻ and Ox⁺ cultures. The influence of growth state and oxygenase activity on biotransformation by each culture was also evaluated. Results indicate that EE2 was the only microconstituent that was amenable to biotransformation by batch cultured AOB and heterotrophic cultures. EE2 was biotransformed but not mineralized by AOB chemostat and batch cultures. TMP was not transformed by AOB batch or chemostat cultures; however both EE2 and TMP were transformed by Ox⁻ and Ox⁺ chemostat cultures. Radiolabeled studies showed that EE2 was mineralized by this culture. Kinetically, AOBs dominated EE2 transformation to monohydroxylated metabolites; however, both Ox⁻ and Ox⁺ cultures further degraded and mineralized EE2 and metabolites generated by AOBs. These results indicate that biotransformation of EE2 by NAS may be limited by heterotrophic activity whereas TMP fate may be a function of heterotrophic activity only. Oxygenase activity did not limit EE2 or TMP biotransformation in chemostat cultures. Subsequent experiments that were performed to identify the factors that influence heterotrophic degradation of EE2 and TMP indicated that the presence of readily biodegradable substrates slows EE2 and TMP biotransformation. The impact of slowly biodegradable substrates like EPS on EE2 and TMP degradation was unclear. These results suggest that EE2 and TMP are most amenable to biodegradation in bioreactors where endogenous conditions dominate. / Ph. D.

The objective of this study was to develop a new method for co-crystal preparation which adhered to green chemistry principles, and provided advantages over conventional methods. A novel, solvent-free, high-power ultrasound (US) technique, for preparing co-crystals from binary systems, was chosen as the technology which could fulfil these aims. The application of this technology for solid state co-crystal preparation was explored for ibuprofen-nicotinamide (IBU-NIC), carbamazepine-nicotinamide (CBZ-NIC) and carbamazepine-saccharin (CBZ-SAC) co-crystals. The effect of different additives and processing parameters such as power level, temperature and sonication time on co-crystallisation was investigated. Characterisation was carried out using DSC, PXRD, FTIR, Raman and HPLC. In addition, an NIR prediction model was developed and combined with multivariate analysis (PLS) and chemometric pre-treatments. It was found to be a robust, reliable and rapid method for the determination of co-crystal purity for the IBU-NIC and CBZ-NIC pairs. Co-crystal quantification of US samples helped to optimise the US method. Finally, a model formulation of paracetamol containing 5% and 10% PEG 8000 was ultrasonicated at maximum power with different exposure times. A comparison of technological and physicochemical properties of the resulting tablets with those of the tablets obtained using the pressing method evidenced significant differences. This suggested that US energy dissipation (mechanical and thermal effects) was the main mechanism which caused the PAR form I tabletability to improve. It was found that the ultrasound–compacted tablets released the drug at a slower rate compared to pure PAR. This technique was shown to be useful for improving tabletability for low-compressible drugs without the need to use a conventional tabletting machine.

The objective of this study was to develop a new method for co-crystal preparation which adhered to green chemistry principles, and provided advantages over conventional methods. A novel, solvent-free, high-power ultrasound (US) technique, for preparing co-crystals from binary systems, was chosen as the technology which could fulfil these aims. The application of this technology for solid state co-crystal preparation was explored for ibuprofen-nicotinamide (IBU-NIC), carbamazepine-nicotinamide (CBZ-NIC) and carbamazepine-saccharin (CBZ-SAC) co-crystals. The effect of different additives and processing parameters such as power level, temperature and sonication time on co-crystallisation was investigated. Characterisation was carried out using DSC, PXRD, FTIR, Raman and HPLC. In addition, an NIR prediction model was developed and combined with multivariate analysis (PLS) and chemometric pre-treatments. It was found to be a robust, reliable and rapid method for the determination of co-crystal purity for the IBU-NIC and CBZ-NIC pairs. Co-crystal quantification of US samples helped to optimise the US method. Finally, a model formulation of paracetamol containing 5% and 10% PEG 8000 was ultrasonicated at maximum power with different exposure times. A comparison of technological and physicochemical properties of the resulting tablets with those of the tablets obtained using the pressing method evidenced significant differences. This suggested that US energy dissipation (mechanical and thermal effects) was the main mechanism which caused the PAR form I tabletability to improve. It was found that the ultrasound–compacted tablets released the drug at a slower rate compared to pure PAR. This technique was shown to be useful for improving tabletability for low-compressible drugs without the need to use a conventional tabletting machine.

<div>Biosolids-based fertilizers are sold to the public to provide beneficial nutrients and organic matter for plant production. They are commonly applied to community gardens, municipal lands, reclamation projects, and golf courses. These fertilizers, however, may also contain a variety of trace organic contaminants, which can be persistent in the environment. Our work sought to quantify the persistence of biosolids contaminants in community garden soils. The commercial biosolids-based fertilizer, OCEANGRO®, was amended to two community garden soils to determine the first-order half-lives of four model contaminants: carbamazepine, miconazole, triclocarban, and triclosan. The criteria for their selection included biosolids occurrence, ecotoxicity, antimicrobial function, and knowledge gaps. Aerobic biosolids-amended soil microcosms were incubated at 22 ± 1 °C and approximately 80% field capacity. Sacrificial sampling occurred seven times over 180 days through multi-step solvent extractions. Detection and quantification were done on a high-performance liquid chromatograph tandem triple-quadrupole mass spectrometer. Results indicated that biosolids contaminants persist in soils with some having modeled half-lives in the hundreds of days. Additional analyses of solvent-spiked contaminant degradation and porewater desorption were performed to provide greater insight into possible limitations on resident biosolids contaminant degradation and to form a better comparative basis to previous literature. Solvent-spiked contaminants degraded more quickly than those resident within biosolids, which indicate that data using the former may underestimate persistence in real-world environments. The porewater analysis allowed for the desorption coefficient to be calculated for all four model resident contaminants. Disparities in the trends of these desorption coefficients and solvent-spiked degradation rates showed that desorption from the biosolids matrix may have been a limiting factor to resident degradation for only some of our four model contaminants. Nonetheless, the demonstrated persistence of these contaminants necessitates long-term thinking in relation to biosolids application. More work is needed on the potential hazards associated with biosolids use in public lands regarding ecotoxicity and antimicrobial resistance.</div>