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  • 1. Alhalaweh, Amjad
    et al.
    Ali, Hassan
    Velaga, Sitaram
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Effects of polymer and surfactant on the dissolution and transformation profiles of cocrystals in aqueous media2014In: Crystal Growth & Design, ISSN 1528-7483, E-ISSN 1528-7505, Vol. 14, no 2, p. 643-648Article in journal (Refereed)
    Abstract [en]

    Capturing solubility advantages of cocrystals is of great interest, and thus to understand the mechanism by which different excipients could maintain the supersaturation generated by cocrystals at the course of absorption in aqueous media is essential. To achieve this aim, the impact of different excipients on dissolution behavior of indomethacin-saccharin (IND-SAC) were monitored by measuring the concentrations of cocrystal components in the absence and presence of various concentration of excipients by HPLC, and solid phases were analyzed by differential scanning calorimetry after each experiment and the potential of Raman spectroscopy for monitoring phase transformations in situ was tested. No dissolution advantage was offered by cocrystals in the absence of any solution additive. The polymer and surfactant used in the study increased the solubility of IND but not SAC. This differential solubilization effect is believed to have stabilized the cocrystals for a relevant period for the absorption to take place. This could be attributed to either decreased gap between supersaturation and saturation of the drug or drug interaction with the additives. Understanding the effects of excipients type and concentration on the transformation profile is vital for designing enabling formulations for cocrystals. The eutectic constant may be useful in selecting excipients for stabilizing cocrystals.

  • 2.
    Ali, Hassan
    et al.
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Alhalaweh, Amjad
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Mendes, N.F.C.
    Ribeiro-Claro, Paulo
    Velaga, Sitaram
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Solid-state vibrational spectroscopic investigation of cocrystals and salt of indomethacin2012In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 14, no 20, p. 6665-6674Article in journal (Refereed)
    Abstract [en]

    Knowledge and control of the solid forms of active pharmaceutical ingredients are important aspects of drug development in the pharmaceutical industry. In this paper, the process of the molecular self-assembly of saccharin cocrystals and the 2-amino-5-methylpyridine salt of indomethacin, in terms of the hydrogen bonding patterns, has been studied in the solid-state using vibrational spectroscopy (Raman and infrared). Interaction patterns in the respective crystalline states were obtained from the single crystal data. The effects of cocrystal and salt formation on the frequencies of the vibrational modes of motion were explained by vibrational spectroscopy and supported by quantum chemical calculations at the density functional theory level, leading to unambiguous assignment of the vibrational spectra of the starting materials and their respective products. Both Raman and infrared spectroscopies were useful, reliable tools for characterizing and distinguishing the indomethacin cocrystals and salt.

  • 3.
    Ali, Hassan
    et al.
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Alhalaweh, Amjad
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Velaga, Sitaram
    Luleå University of Technology, Department of Health Sciences, Medical Science.
    Vibrational spectroscopic investigation of polymorphs and cocrystals of indomethacin2013In: Drug Development and Industrial Pharmacy, ISSN 0363-9045, E-ISSN 1520-5762, Vol. 39, no 5, p. 625-634Article in journal (Refereed)
    Abstract [en]

    Context:Identification of optimal solid form of an active pharmaceutical ingredient and form control are very important in drug development. Thus, the structural information of these forms and in-depth insight on the modes of molecular interactions are necessary, and vibrational spectroscopic methods are well suited for this purpose.Objective:In-depth structural analysis of different solid forms of indomethacin (IND) using Raman and infrared (IR) spectroscopy is the objective. We have investigated the modes of molecular interactions in polymorphs (α and γ), amorphous and discovered cocrystals of IND with nicotinamide (NIC) and trans-cinnamic acid (CIN) coformers.Materials and methods: The solid forms of IND have been prepared; their purity has been verified by differential scanning calorimetry and powder X-ray diffractometry and then studied in the solid-state by Raman and IR spectroscopy. The modes of the interactions were closely investigated from the vibrational data.Results: The key vibrational features of IND solid forms have been specified. The IR (C=O) band at 1713 cm−1 attributed to cyclic acid dimer of γ IND has disappeared in IND–NIC/CIN whilst retained in IND–SAC cocrystal.Discussion:IND cocrystallizes in different conformations and crystal lattices with different coformers. The cyclic acid dimer of IND has been kept on its cocrystallization with saccharin and it could have been broken with NIC and CIN.Conclusions: The complementary nature of Raman and IR spectroscopy allowed unambiguous investigation of the chemical composition of pharmaceutical materials which is of particular importance in the absence of detailed structural information, as in the case of IND–NIC and IND–CIN.

  • 4. Ali, Hassan
    et al.
    Edwards, Hoewll G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Kendrick, J.
    Institute of Pharmaceutical Innovation, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Vibrational spectroscopic study of terbutaline hemisulphate2009In: Spectrochimica Acta Part A - Molecular and Biomolecular Spectroscopy, ISSN 1386-1425, E-ISSN 1873-3557, Vol. 72, no 4, p. 715-719Article in journal (Refereed)
    Abstract [en]

    The Raman spectrum of terbutaline hemisulphate is reported for the first time, and molecular assignments are proposed on the basis of ab initio BLYP DFT calculations with a 6-31G* basis set and vibrational frequencies predicted within the quasi-harmonic approximation; these predictions compare favourably with the observed vibrational spectra. Comparison with previously published infrared data explains several spectral features. The results from this study provide data that can be used for the preparative process monitoring of terbutaline hemisulphate, an important β2 agonist drug in various dosage forms and its interaction with excipients and other components

  • 5. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Hargreaves, Michael D.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Munshi, Tasnim
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Telford, Richard J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Vibrational spectroscopic characterisation of salmeterol xinafoate polymorphs and a preliminary investigation of their transformation using simultaneous in situ portable Raman spectroscopy and differential scanning calorimetry2008In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 620, no 1-2, p. 103-12Article in journal (Refereed)
    Abstract [en]

    Knowledge and control of the polymorphic phases of chemical compounds are important aspects of drug development in the pharmaceutical industry. Salmeterol xinafoate, a long acting beta-adrenergic receptor agonist, exists in two polymorphic Forms, I and II. Raman and near infrared spectra were obtained of these polymorphs at selected wavelengths in the range of 488-1064 nm; significant differences in the Raman and near-infrared spectra were apparent and key spectral marker bands have been identified for the vibrational spectroscopic characterisation of the individual polymorphs which were also characterised with X ray diffractometry. The solid-state transition of salmeterol xinafoate polymorphs was studied using simultaneous in situ portable Raman spectroscopy and differential scanning calorimetry isothermally between transitions. This method assisted in the unambiguous characterisation of the two polymorphic forms by providing a simultaneous probe of both the thermal and vibrational data. The study demonstrates the value of a rapid in situ analysis of a drug polymorph which can be of potential value for at-line in-process control

  • 6. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Kendrick, J.
    Institute of Pharmaceutical Innovation, University of Bradford.
    Munchi, Tasnim
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Vibrational spectroscopic study of budesonide2007In: Journal of Raman Spectroscopy, ISSN 0377-0486, E-ISSN 1097-4555, Vol. 38, no 7, p. 903-908Article in journal (Refereed)
    Abstract [en]

    The Raman spectrum of budesonide is reported for the first time, and molecular assignments are proposed on the basis of ab initio BLYP DFT calculations with a 6-31 G* basis set and vibrational wavenumbers predicted on a quasi-harmonic approximation. Comparison with previously published infrared data has explained several spectral features, and the relative band intensities in the C=O and C=C stretching regions are interpreted. The results from this study provide data that can be used for the preparative process monitoring of budesonide, an important steroidal pharmaceutical in various dosage forms, and its interaction with excipients and other components

  • 7. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Kendrick, J.
    Institute of Pharmaceutical Innovation, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    An experimental and computational study on the epimeric contribution to the infrared spectrum of budesonide2010In: Drug Testing and Analysis, ISSN 1942-7603, E-ISSN 1942-7611, Vol. 2, no 9, p. 447-451Article in journal (Refereed)
    Abstract [en]

    Budesonide is a mixture of 22R and 22S epimers. The epimeric content of budesonide was reported in both British and European pharmacopoeias to be within the range of 60-49/40-51 for R and S epimers, respectively. In this work, contribution of the two epimers to the overall infrared spectrum of budesonide has been investigated by quantum chemical calculations

  • 8. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Kendrick, J.
    Institute of Pharmaceutical Innovation, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Computational and vibrational spectroscopic studies of ipratropium bromide2009In: Drug Testing and Analysis, ISSN 1942-7603, E-ISSN 1942-7611, Vol. 1, no 2, p. 73-80Article in journal (Refereed)
    Abstract [en]

    In this study, ipratropium bromide is investigated using vibrational spectroscopy and quantum chemical calculations. The structure of ipratropium bromide was optimised using density functional theory calculations and the geometry optimisation has been carried out on two conformations with and without intramolecular hydrogen bonding. Infrared and Raman spectra were calculated from the optimised structures. Manymodes in the calculated spectra could bematched with the experimental spectra and a description of the modes is given. By analysis of the theoretical vibrational modes, it is shown that ipratropium bromide specimens are likely to beamixture of the two conformations with and without intramolecular hydrogen bonding. In addition, several spectral features and band intensities in the CH and OH stretching regions are explained. Quantum mechanical calculations allowed improved understanding of ipratropium bromide and its vibrational spectra

  • 9. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Kendrick, J.
    Institute of Pharmaceutical Innovation, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Vibrational spectroscopic study of fluticasone propionate2009In: Spectrochimica Acta Part A - Molecular and Biomolecular Spectroscopy, ISSN 1386-1425, E-ISSN 1873-3557, Vol. 72, no 2, p. 244-247Article in journal (Refereed)
    Abstract [en]

    Fluticasone propionate is a synthetic glucocorticoid with potent anti-inflammatory activity that has been used effectively in the treatment of chronic asthma. The present work reports a vibrational spectroscopic study of fluticasone propionate and gives proposed molecular assignments on the basis of ab initio calculations using BLYP density functional theory with a 6-31G* basis set and vibrational frequencies predicted within the quasi-harmonic approximation. Several spectral features and band intensities are explained. This study generated a library of information that can be employed to aid the process monitoring of fluticasone propionate.

  • 10. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Kendrick, J.
    Institute of Pharmaceutical Innovation, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Vibrational spectroscopic study of salbutamol hemisulphate2009In: Drug Testing and Analysis, ISSN 1942-7603, E-ISSN 1942-7611, Vol. 1, no 1, p. 51-56Article in journal (Refereed)
    Abstract [en]

    Salbutamol hemisulphate is a relatively selective β 2-adrenergic agonist and is used as a bronchodilator. In this work, we present a detailed vibrational spectroscopic investigation of salbutamol hemisulphate using mid-infrared and near-infrared Fourier-transform (NIR-FT) Raman spectroscopies. These data are supported by quantum chemical calculations, which allow us to characterise the vibrational spectra of this compound reasonably. As such, this study could be viable for examining the way in which this drug interacts with its targetmolecules.

  • 11. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Insight into thermally induced solid-state polymorphic transformation of sulfathiazole using simultaneous in situ Raman spectroscopy and differential scanning calorimetry2009In: Journal of Raman Spectroscopy, ISSN 0377-0486, E-ISSN 1097-4555, Vol. 40, no 8, p. 887-892Article in journal (Refereed)
    Abstract [en]

    Pharmaceutical solids exposed to thermal stress during manufacturing processes undergo various phase transformations in bulk drug substances or excipients, resulting in altered dosage form performance. Due to its relatively rapid spectral acquisition rate, as well as the possibility of incorporation into in-line monitoring, Raman spectroscopy is ideally suited to monitoring the transformation between different solid-state forms. In this study, we demonstrate that the transition temperature for polymorphs can be estimated from the transformation profiles obtained from real-time, in situ, simultaneous Raman spectroscopic, and differential scanning calorimetric data. Using this method, we have estimated the transition temperature of the solid-state transformation of the enantiotropically related sulfathiazole polymorphs III and I. These results suggest that this method is a useful approach to determine transition temperatures in systems that are not amenable to accessing other methods

  • 12. Ali, Hassan
    et al.
    Edwards, Howell G.M.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Scowen, Ian J.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Noninvasive in situ identification and band assignments of some pharmaceutical excipients inside USP vials with FT-near-infrared spectroscopy2009In: Spectrochimica Acta Part A - Molecular and Biomolecular Spectroscopy, ISSN 1386-1425, E-ISSN 1873-3557, Vol. 72, no 4, p. 890-896Article in journal (Refereed)
    Abstract [en]

    For the manufacture of dosage forms all ingredients must be reliably identified. In this paper, the suitability of FT-NIR spectroscopy to identify potassium sorbate, sodium starch glycollate, calcium ascorbate, calcium carbonate, candelilla wax, maltosextrin, monohydrated and anhydrous lactose inside USP vials was investigated. Differentiation between the anhydrous and monohydrated forms of lactose was found to be possible by studying the regions of the near-infrared spectrum corresponding to the combination and first overtone stretching frequencies of water. The results show unequivocally the potential of FT-NIR spectroscopy for rapid, in situ and non-destructive identification of pharmaceutical excipients

  • 13.
    Edwards, Howell G.M.
    et al.
    Chemical and Forensic Sciences, School of Life Sciences, University of Bradford.
    Currie, Katherine J.
    KNH Centre for Biomedical Egyptology, University of Manchester.
    Ali, Hassan
    Villar, Susana E. Jorge
    Area de Geodinamica Interna, Facultad de Humanidades y Educacion, Universidad de Burgos.
    David, A. Rosalie
    KNH Centre for Biomedical Egyptology, University of Manchester.
    Denton, John
    KNH Centre for Biomedical Egyptology, University of Manchester.
    Raman spectroscopy of natron: Shedding light on ancient Egyptian mummification2007In: Analusis, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 388, no 3, p. 683-689Article in journal (Refereed)
    Abstract [en]

    The mummification ritual in ancient Egypt involved the evisceration of the corpse and its desiccation using natron, a naturally occurring evaporitic mineral deposit from the Wadi Natrun, Egypt. The deposit typically contains sodium carbonate, sodium bicarbonate and impurities of chloride and sulfate as its major elemental components. It is believed that the function of the natron was to rapidly remove the water from the cadaver to prevent microbial attack associated with subsequent biological tissue degradation and putrefaction. Several specimens of natron that were recently collected from the Wadi Natrun contained coloured zones interspersed with the mineral matrix that are superficially reminiscent of extremophilic cyanobacterial colonisation found elsewhere in hot and cold deserts. Raman spectroscopy of these specimens using visible and near-infrared laser excitation has revealed not only the mineral composition of the natron, but also evidence for the presence of cyanobacterial colonies in several coloured zones observed in the mineral matrix. Key Raman biosignatures of carotenoids, scytonemin and chlorophyll have been identified

  • 14.
    Mohamed, A.I.
    et al.
    University of Assiut.
    el-Shabouri, S.R.
    University of Assiut.
    Abdel-Wadood, H.M-
    University of Assiut.
    Ali, Hassan
    Spectrofluorometric determination of certain local anesthetics2002In: Bulletin of the Faculty of Science, Assiut University - Section B: Chemistry, ISSN 1010-2671, Vol. 31, no 2, p. 39-57Article in journal (Refereed)
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