Yes / The design of a melt synthesis of the first air-stable formulation of the metastable form III of paracetamol is derived from thermo-spectroscopic and thermo-diffraction experiments. Melt crystallisation in the presence of β-1,4-saccharides produces form III selectively and the excipients appear to act as stabilising ‘active’ templates of the metastable polymorph. / This article is part of themed collection: Pharmaceutical Solids.

Yes / Insights into structure–mechanical property correlations in molecular and multicomponent crystals have recently attracted significant attention owing to their practical applications in the pharmaceutical and specialty fine chemicals manufacturing. In this contribution, we systematically examine the mechanical properties of dimorphic forms, Forms I and II of 1:1 caffeine-glutaric acid cocrystal on multiple faces using nanoindentation to fully understand their mechanical anisotropy and mechanical stability under applied load. Higher hardness, H, and elastic modulus, E, of stable Form II has been rationalized based on its corrugated layers, higher interlayer energy, lower interlayer separation, and presence of more intermolecular interactions in the crystal structure compared to metastable Form I. Our results show that mechanical anisotropy in both polymorphs arises due to the difference in orientation of the same 2D structural features, namely the number of possible slip systems, and strength of the intermolecular interactions with respect to the indentation direction. The mechanical properties results suggest that 1:1 caffeine-glutaric acid cocrystal, metastable form (Form I) could be a suitable candidate with desired tablet performance to that of stable Form II. The overall, it demonstrates that the multiple faces of nanoindentation is critical to determine mechanical anisotropy and structure- mechanical property correlation. Further, the structural-mechanical property correlations aids in the selection of the best solid phase for macroscopic pharmaceutical formulation.

The knowledge of the packing behaviour of small organic compounds in crystal lattices is of great importance for industries dealing with solid state materials. The properties of materials depend on how the molecules arrange themselves in a crystalline environment. Crystal structure prediction provides a theoretical approach through the application of computational strategies to seek possible crystal packing arrangements (or polymorphs) a compound may adopt. Based on the chemical diagrams, this thesis investigates polymorphism of several small organic compounds. Plausible crystal packings of those compounds are generated, and their lattice energies are minimised using molecular mechanics and/or quantum mechanics methods. Most of the work presented here is conducted using two software packages commercially available in this field, Polymorph Predictor of Materials Studio 4.0 and GRACE 1.0. In general, the computational techniques implemented in GRACE are very good at reproducing the geometries of the crystal structures corresponding to the experimental observations of the compounds, in addition to describing their solid state energetics correctly. Complementing the CSP results obtained using GRACE with isostructurality offers a route by which new potential polymorphs of the targeted compounds might be crystallised using the existing experimental data. Based on all calculations in this thesis, four new potential polymorphs for four different compounds, which have not yet been determined experimentally, are predicted to exist and may be obtained under the right crystallisation conditions. One polymorph is expected to crystallise under pressure. The remaining three polymorphs might be obtained by using a seeding technique or the utilisation of suitable tailor made additives. / University of Bradford

The aim of this work was to assess the suitability of vibrational spectroscopic techniques (Raman, FT-IR and FT-NIR spectroscopy) as a means for the solid-state structural analysis of pharmaceuticals. Budesonide, fluticasone propionate, salbutamol hemisulfate, terbutaline hemisulfate, ipratropium bromide, polymorphic forms of salmeterol xinafoate and two polymorphic forms of sulfathiazole were selected since they are used in the management of certain respiratory disorders and from different chemical and pharmacological entities along with some pharmaceutical excipients. Conventional visual examination is not sufficient to identify and differentiate spectra between different pharmaceuticals. To confirm the assignment of key molecular vibrational band signatures, quantum chemical calculations of the vibrational spectra were employed for better understanding of the first five selected drugs. The nondestructive nature of the vibrational spectroscopic techniques and the success of quantum chemical calculations demonstrated in this work have indeed offered a new dimension for the rapid identification and characterisation of pharmaceuticals and essentially warrant further research. The application of simultaneous in situ Raman spectroscopy and differential scanning calorimetry for the preliminary investigation of the polymorphic transformation of salmeterol xinafoate polymorphs and two polymorphic forms of sulfathiazole has also been explored in this work leading to the development of a new method for the solid-state estimation of the transition temperature of entantiotropically related pharmaceutical polymorphs which represents the first analytical record of the use of this approach for pharmaceutical polymorphs.

The knowledge of the packing behaviour of small organic compounds in crystal lattices is of great importance for industries dealing with solid state materials. The properties of materials depend on how the molecules arrange themselves in a crystalline environment. Crystal structure prediction provides a theoretical approach through the application of computational strategies to seek possible crystal packing arrangements (or polymorphs) a compound may adopt. Based on the chemical diagrams, this thesis investigates polymorphism of several small organic compounds. Plausible crystal packings of those compounds are generated, and their lattice energies are minimised using molecular mechanics and/or quantum mechanics methods. Most of the work presented here is conducted using two software packages commercially available in this field, Polymorph Predictor of Materials Studio 4.0 and GRACE 1.0. In general, the computational techniques implemented in GRACE are very good at reproducing the geometries of the crystal structures corresponding to the experimental observations of the compounds, in addition to describing their solid state energetics correctly. Complementing the CSP results obtained using GRACE with isostructurality offers a route by which new potential polymorphs of the targeted compounds might be crystallised using the existing experimental data. Based on all calculations in this thesis, four new potential polymorphs for four different compounds, which have not yet been determined experimentally, are predicted to exist and may be obtained under the right crystallisation conditions. One polymorph is expected to crystallise under pressure. The remaining three polymorphs might be obtained by using a seeding technique or the utilisation of suitable tailor made additives.

Made available in DSpace on 2016-03-04T13:55:11Z (GMT). No. of bitstreams: 2 6.pdf: 5451306 bytes, checksum: 8e6c41055d0d4b7e199d2953a031020b (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz. Instituto de Tecnologia em Fármacos/Farmanguinhos. Rio de Janeiro, RJ, Brasil. / A olanzapina é um fármaco antipsicótico de segunda geração indicada no tratamento da esquizofrenia e do transtorno bipolar. O fármaco pode ser cristalizado em mais de 25 formas diferentes: três anidras (I, II e III), três polimorfos diidratados (B, D e E), um hidrato maior, além de inúmeros solvatos. A olanzapina é uma base fraca, com solubilidade dependente de pH, sendo solúvel em soluções ácidas e pouco solúvel em meio básico. O fármaco pertence à classe II do Sistema de Classificação Biofarmacêutica. Em função de suas características de cristalinidade e solubilidade, lotes de olanzapina de três fabricantes diferentes foram caracterizados quanto às suas propriedades físico-químicas, com o objetivo de subsidiar o desenvolvimento de um medicamento similar de comprimidos revestidos de olanzapina. Além dos ensaios previstos na monografia da matéria-prima na Farmacopéia Americana (USP, 2013), as amostras foram analisadas por difração de raios X, espectroscopia no infravermelho, análise térmica, microscopia, difração de LASER e estudos de solubilidade e dissolução. Os resultados obtidos indicam que as amostras avaliadas são compostas de misturas dos polimorfos anidros I e II da olanzapina. Os lotes também apresentaram diferentes distribuições de tamanho de partículas. No entanto, as diferenças na granulometria e cristalinidade não corresponderam a diferenças significativas na solubilidade e dissolução das amostras em diferentes meios com pH na faixa fisiológica. A partir dos resultados dos estudos de pré-formulação, foram propostas formulações por compressão direta para o medicamento olanzapina comprimidos revestidos na concentração de 10 mg. As formulações foram avaliadas quanto à conformidade com os ensaios previstos em compêndios oficiais e quanto à similaridade dos perfis de dissolução in vitro com os perfis obtidos para o medicamento referência no mercado nacional. Os resultados obtidos demonstram a equivalência das formulações testadas com as amostras dos diferentes fabricantes em relação ao medicamento referência, nos meios de dissolução com pH entre 1,2 a 6,8. / Olanzapine is a second generation antipsychotic drug indicated for the treatment of schizophrenia and bipolar disorder. The drug crystallizes in more than 25 different forms: three anhydrates (I, II and III ), three polymorphic dihydrates (B, D , and E), a higher hydrate and numerous solvates . Olanzapine is a weak base with pH dependent solubility and is soluble in acidic solutions and slightly soluble in basic medium. The drug belongs to the class II of the Biopharmaceutical Classification System. Due to its characteristics of crystallinity and solubility, three lots of olanzapine from different manufacturers were evaluated according to their physicochemical properties, with the aim of supporting the development of similar drug olanzapine coated tablets. In addition to the tests described in the monograph of raw material in the United States Pharmacopoeia (USP, 2013), the samples were analyzed by X ray diffraction, infrared spectroscopy, thermal analysis, microscopy, LASER diffraction and solubility and dissolution studies. The results indicate the samples tested are composed of mixtures of the anhydrous polymorphs I and II of olanzapine. The lots also had different particle size distributions. However, differences in crystallinity and particle size does not correspond to differences in the solubility and dissolution of the samples in different media in the physiological pH range. Considering the results of the preformulation studies, direct compression formulation for coated tablets of olanzapine 10 mg were proposed. The formulations were evaluated for compliance with the tests described in official compendia and the similarity of the in vitro dissolution profiles with the profiles obtained for the reference product in the Brazilian Market. The results obtained demonstrate the equivalence of the formulations tested with samples from different manufacturers in relation to the reference drug in dissolution media with pH between 1.2 to 6.8.

Diploma thesis deals with laboratory preparation of the main clinker mineral - alit. The theoretical part summarizes the existing knowledge and the practical part deals with the methodology of preparation of the alite. The main goal was to prepare and study the monoclinic phases of alite, another goal was to optimize the triclinic alite.

The aim of this work was to assess the suitability of vibrational spectroscopic techniques (Raman, FT-IR and FT-NIR spectroscopy) as a means for the solid-state structural analysis of pharmaceuticals. Budesonide, fluticasone propionate, salbutamol hemisulfate, terbutaline hemisulfate, ipratropium bromide, polymorphic forms of salmeterol xinafoate and two polymorphic forms of sulfathiazole were selected since they are used in the management of certain respiratory disorders and from different chemical and pharmacological entities along with some pharmaceutical excipients. Conventional visual examination is not sufficient to identify and differentiate spectra between different pharmaceuticals. To confirm the assignment of key molecular vibrational band signatures, quantum chemical calculations of the vibrational spectra were employed for better understanding of the first five selected drugs. The nondestructive nature of the vibrational spectroscopic techniques and the success of quantum chemical calculations demonstrated in this work have indeed offered a new dimension for the rapid identification and characterisation of pharmaceuticals and essentially warrant further research. The application of simultaneous in situ Raman spectroscopy and differential scanning calorimetry for the preliminary investigation of the polymorphic transformation of salmeterol xinafoate polymorphs and two polymorphic forms of sulfathiazole has also been explored in this work leading to the development of a new method for the solid-state estimation of the transition temperature of entantiotropically related pharmaceutical polymorphs which represents the first analytical record of the use of this approach for pharmaceutical polymorphs.

The process of milling drugs to obtain samples with a desirable particle size range has been widely used in the pharmaceutical industry, especially for the production of drugs for inhalation. However by subjecting materials to milling techniques surfaces may become thermodynamically activated which may in turn lead to formation of amorphous material. Polymorphic conversions have also been noted after milling of certain materials. Salt and cocrystal formation is a good way of enhancing the properties of an API but little or no work has been published which investigates the stability of these entities when subjected to milling. Different milling techniques (ball and jet) and temperatures (ambient and cryogenic) were used to investigate the milling behaviour of polymorphs, salts and cocrystals. All materials were analysed by XRPD and DSC to investigate any physical changes, i.e. changes in melting point and by inverse gas chromatography (IGC) to investigate whether any changes in the surface energetics occurred as a result of milling. Another aim of this thesis was to see if it was possible to predict the milling behaviour of polymorphs by calculating the attachment energies of the different crystal facets using Materials Studio 4.0. These results were compared to the IGC data to see if the predicted surface changes had occurred. The data collected in this study showed that different milling techniques can have a different effect on the same material. For example ball milling at ambient temperature and jet micronisation of the SFZ tosylate salt caused a notable increase in the melting point of the material whereas ball milling at cryogenic temperatures did not cause this to happen. The IGC data collected for this form also showed a contrast between cryomilling and the other two techniques. The study also showed that the formation of salts and cocrystals does not necessarily offer any increased stability in terms of physical properties or surface energetics. Changes in melting point were observed for the SFZ tosylate salt and the IMC:Benzamide cocrystal. Changes in the specific surface energies were also observed indicating that the nature of the surfaces was also changing. The materials which appeared to be affected the least were the two stable polymorphs, gamma IMC and SFZ III. The computational approach used has many limitations. The software does not allow for conversion to the amorphous form or polymorphic conversions. Such conversions were seen to occur, particularly for the metastable polymorphs used, meaning that this computational approach may only be suitable for stable polymorphs.

Στο πλαίσιο της παρούσας εργασίας έγινε προσπάθεια για την ανάπτυξη αναλυτικών μεθοδολογιών με στόχο την ταυτοποίηση και την ποσοτική ανάλυση σε περιπτώσεις ταυτόχρονης συνύπαρξης και των τριών φάσεων του άνυδρου κρυσταλλικού ανθρακικού ασβεστίου. Η Φασματοσκοπία Raman και η Φασματοσκοπία Υπερύθρου ήταν οι δύο αναλυτικές τεχνικές οι οποίες χρησιμοποιήθηκαν σαν βάση για την ανάπτυξη των ανάλογων αναλυτικών μεθοδολογιών. Η χρήση της Φασματοσκοπίας Raman οδήγησε στην ανάπτυξη μιας μη καταστροφικής αναλυτικής μεθοδολογίας, στην οποία όμως μόνο τα σχετικά ποσοστά των τριών φάσεων έγινε δυνατόν να προσδιοριστούν. Για την δημιουργία των ευθειών αναφοράς, κατασκευάστηκαν δυαδικά μίγματα, ενώ χρησιμοποιήθηκαν οι κορυφές στα 711cm-1 για τον ασβεστίτη, στα 700cm-1 για τον αραγωνίτη και στα 750cm-1 για τον βατερίτη. Τα όρια ανίχνευσης προσδιορίστηκαν 0.13mol%, 0.18mol% και 1.3mol% για τον ασβεστίτη, αραγωνίτη και βατερίτη αντίστοιχα, ενώ τα σφάλματα κατά τον προσδιορισμό τριαδικού μίγματος γνωστής σύστασης βρέθησαν να είναι 1.6mol% για τον ασβεστίτη, 0.3mol% για τον αραγωνίτη και 1.1mol% για τον βατερίτη. Στην προσπάθεια επιλογής των κατάλληλων δονήσεων Raman, έγινε μελέτη των φασμάτων Raman των καθαρών κρυσταλλικών φάσεων και απόδοση των κορυφών. Τέλος με την χρήση της Φασματοσκοπίας IR έγινε δυνατός ο προσδιορισμός των απόλυτων ποσοστών των τριών φάσεων, κάνοντας χρήση των δονήσεων στα 714cm-1 για τον ασβεστίτη, στα 700cm-1 και 714cm-1 για τον αραγωνίτη και στα 745cm-1 για τον βατερίτη. Οι απόρροφητικότητες των κορυφών (σε mg-1CaCO3 mm-2) βρέθηκαν ίσες με: α 63.38 714 = για τον ασβεστίτη, α .30 700 = 19 και α .43 714 = 40 για τον αραγωνίτη και α .79 745 = 21 για τον βατερίτη. Τα όρια ανίχνευσης (σε mgCaCO3/mm2) προσδιορίστηκαν σε: 714 -4 C O.A. =6.6 ×10 για τον ασβεστίτη, 700 -3 A O.A. =2.2 ×10 και 714 -3 A O.A. =1.1×10 για τον αραγωνίτη και 745 -3 V O.A. =1.9 ×10 για τον βατερίτη. / In the present work new analytical methodologies were developed for the study of calcium carbonate polymorphs (calcite, aragonite, vaterite). Two vibrational techniques were employed for the simultaneous quantitative analysis of mixtures of crystalline materials; Raman Spectroscopy (non-destructive technique), Infrared Spectroscopy (destructive technique). Using binary mixtures from known quantities of the crystal phase the calibration curves were constructed using the Raman bands at 711cm-1 for calcite, 700cm-1 for aragonite and 750cm-1 for vaterite. Detection limits (DL) were found to be 0.13, 0.18 and 1.3mol % for calcite, aragonite and vaterite, respectively, while the relative errors in determining the mol % of a known ternary mixture of calcium carbonate polymorphs were 1.6% for calcite, 0.3% for aragonite and 1.1% for vaterite. Infrared Spectroscopy was used, in order to determinate the absolute concentration of the calcium carbonate crystal phases, using the bands at 714cm-1 for calcite, at 700cm- 1 and 714cm-1 for aragonite and at 745cm-1 for vaterite. The asborptivities were found to be α 63.38 714 = for calcite, α .30 700 = 19 and α .43 714 = 40 for aragonite and α .79 745 = 21 for vaterite. The detection limits were also established and found to be 714 -4 C D.L. = 6.6 ×10 for calcite, 700 -3 A D.L. = 2.2 ×10 and 714 -3 A D.L. =1.1×10 for aragonite and 745 -3 V D.L. = 1.9 ×10 for vaterite.