Browsing by Author "Armitage, R."
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Item Metadata only Counterfeit or just poor quality?(APS, 2017-09-05) Armitage, R.; Lawson, Graham; Tanna, SangeetaCounterfeit medicines are a major public health issue. The World Health Organisation suggests that the occurrence of counterfeits range from 1% in high income countries to as much as ~30-40% in low to middle income countries, however many of these may be substandard rather than counterfeit due to poor quality control. This research investigates the potential of Attenuated Total Reflectance Fourier Transform Infrared (ATR FTIR) techniques to provide rapid quantitative analysis of suspect tablet formulations. Sample preparation for ATR FTIR is minimal and only requires a single tablet to be ground to a fine powder prior to analysis. This enables more rapid analysis of tablets. Reference spectra of the active pharmaceutical ingredient (API) and excipients were recorded for identification purposes. Using atenolol as a model, quantitative data was obtained from calibrated mixtures of API and excipients. Tablets from various countries, India, Saudi Arabia, Nepal and UK were analysed using both ATR FTIR and reference UV analyses. Results demonstrated that the API was detectable down to ca 5% w/w of the tablet. Several examples of poor dosage quality control were identified.Item Embargo The effect of paint type on the development of latent fingermarks on walls(Elsevier, 2020-02-07) Dawkins, Jo; Gautam, Lata; Bandey, Helen; Armitage, R.; Ferguson, LeesaDespite recent advances in DNA technology, fingermark evidence remains a fundamental method of ascertaining an individual’s identity. Latent fingermarks are the commonest type of fingermark encountered at crime scenes. The Fingermark Visualisation Manual provides crime scene practitioner’s with sequential information regarding which enhancement processes are best suited for a range of deposition surfaces (Bandey et al., 2014) [1]. However, there are still many surfaces, such as painted walls where more knowledge is required regarding which development techniques provide optimum results. In this study, four paint types were tested (matt, silk, bathroom and eggshell). Fingermarks were deposited on painted simulated walls and aged for 1 day, 1 week and 1 month. Fingermarks were developed by three processes highlighted as the most frequently used by practitioners (magnetic granular powder, magneta flake powder and ninhydrin). The results showed that overall black magnetic granular powder outperformed both magneta flake powder and ninhydrin on all paint types. This contradicts current UK guidelines for enhancement of fingermarks on matt painted walls, as black magnetic granular powder is not a recommended process at present. SEM and SEM-EDX analysis showed distinct differences between matt paint and the three non-matt paints tested, which provides an explanation for the results obtained.Item Metadata only Fast identification of counterfeit medicines - a comparison of two MS systems(2016-08-20) Lawson, Graham; Ogwu, John; Armitage, R.; Alcroft, Clive; Tanna, SangeetaComparison of a heated atmospheric pressure ionisation (APCI) MS with a vacuum solids probe MS method for the identification of the active pharmaceutical ingredients (API) in powdered fully formulated tablet samples was carried out. Thermal volatilisation allowed direct identification of the APIs at therapeutic levels, in a matter of minutes, in many tablet formulations. Reference spectra were recorded for pure APIs using the Advion ASAP (APCI) probe and the Bruker vacuum insertion probe. Powder samples in the probe cup were transferred to the MS systems and heated in flowing nitrogen at 300C (ASAP) and 40-250C (Bruker). Crushed globally sourced tablet samples were analysed as above. Comparison of the results with tablet labels identified some suspect tablets. Thermal vaporization is needed for the analysis of these samples. In APCI the vaporized API is ionised by corona discharge to give M+H+ ions with little fragmentation. Observed signals were: acetaminophen m/z 152,110; caffeine m/z 195, 138; chloroquine phosphate m/z 320, 247 and atenolol m/z 267, 225. Aspirin was detected as a -ve ion at m/z 179, 137. The simplicity of these spectra meant that tablets containing several APIs could be readily identified: acetaminophen/caffeine/aspirin or artemether and lumifantrine in antimalarial tablets. Electron impact is more energetic giving some fragmentation. EI observed signals were: acetaminophen m/z 151,110; caffeine m/z 194, 109; chloroquine phosphate m/z 320, 247 and atenolol m/z 251, 223. Aspirin was detected as a +ve ion at m/z 138, 120. Tablet and reference data was directly comparable. Analysis time was only minutes per sample. Direct MS analysis of APIs in fully formulated tablet medicines to identify counterfeit or substandard products is novel.Item Metadata only Identification of Counterfeit Drugs(2012-11) Lawson, Graham; Armitage, R.; Tanna, SangeetaItem Metadata only Identification of counterfeit medicines(7th Annual Pharmaceutical Anti-Counterfeiting Meeting. 2012, Visiongain Conference Centre, Barbican, London, UK. 26-27 June., 2012-06-27) Lawson, Graham; Armitage, R.; Tanna, SangeetaMethods for the rapid identification of counterfeit medicines were presented.Item Metadata only Identification of counterfeit pills - Is rapid instrumental analysis possible?(2013-07) Tanna, Sangeeta; Armitage, R.; Lawson, GrahamIntroduction: The manufacture and supply of medicines is a global business and the shipment of millions of dosage forms presents huge challenges to ensuring the safety of the medication reaching the patient. According to the WHO[1] counterfeits may have: no active ingredients present, the wrong level of ingredients, the wrong ingredients, high levels of contaminants or be in counterfeit packaging. This research examines the possibility of replacing sophisticated laboratory tests with simpler and therefore faster bench top tests. Methods: Attenuated Total Reflection (ATR) FT/IR spectroscopy has been investigated as a replacement technique to the conventional methods cited in the British Pharmacopoeia BP 2012[2]. The BP methodology requires the sample to be crushed, solvent extracted, the solvent evaporated and the residue prepared as a KBr disc prior to running the IR fingerprint for identification. Several hours are required for this procedure. ATR FT/IR analyses only require the sample to be ground to a powder which is then spread over the reflection cell to allow the fingerprint spectrum to be recorded. The time scale for these measurements is several minutes only. A range of samples of caffeine, paracetamol, atenolol and sildenafil were subjected to ATR FT/IR analysis in order to investigate: • the effects of different excipients • the ability to identify the presence of the target drug at different doses • the ability to identify the presence of more than one target drug in tablets with multiple actives. These were studied as standards in conventional magnesium stearate/dibasic calcium phosphate excipients and in different therapeutic ’pill’ dosage forms. Results: The ATR FT/IR analyses have proved to be much faster that the BP methods and have also demonstrated the provision of high quality spectral data without the need for extensive laboratory training of staff. Not only was the ATR FT/IR system able to identify single and mixed components the detection capabilities of this system were better (2X) than those reported by Khinchi et al [3]. Conclusions: The ATR FT/IR system has demonstrated the ability to confirm the presence of both good and counterfeit materials in simple selected tablet dosage forms. Paracetamol, caffeine and atenolol could all be detected at levels down to ca 4.0% in pill formulations. A more extensive survey is currently being undertaken.Item Metadata only Is it what it says on the packet? ATR FTIR provides a rapid answer to counterfeit tablet formulations(Executive Committee of British Global Travel Health Association, 2014-07) Lawson, Graham; Turay, Edward; Armitage, R.; Goodyer, Larry; Tanna, SangeetaItem Open Access On a Knife Edge: A preliminary investigation of clothing damage using rounded-tip knives(Elsevier, 2020-08-15) Nichols-Drew, L.; Armitage, R.; Sheridan, Kelly; Hillman, Rob; Farrugia, Kevin J.Bladed weapons are frequently encountered in violent crime offences including street based and armed robberies, murder, sexual assaults and terrorism. A study was conducted involving four frequently encountered clothing fabrics: t-shirt (knitted cotton), denim jeans (twill woven cotton), long sleeved top (knitted synthetic blend), and skirt (non-woven faux leather) and five knives to investigate any damage resulting from a downward stabbing motion, with 300 stabs in total. Any resultant penetrating severance damage was then photographed, measured and analysed. Statistical analysis revealed significant differences between the stab hole size and shape, as a consequence of the design of a bladed weapon (in particular, the tip shape) that caused it. There is a notable correlation between the Assure knife (rounded tip) and no resulting severance damage, as the fabric surfaces were not breached with this knife. This suggests a clear alternative to pointed tip knife blades. These findings will be of interest to investigators of knife crime offences, crime-reduction units, knife manufacturers and practitioners, who share the goal of identifying a safer alternative to conventional knife blade design.Item Open Access Poor-quality medicines are everyone's problem(360info, 2022-07-27) Tanna, Sangeeta; Armitage, R.Item Metadata only Rapid identification of counterfeit pills by ATR FT/IR analysis of crushed samples(OMICS Publishing Group, 2013-10) Lawson, Graham; Armitage, R.; Alhedethe, Abdulaziz; Tanna, SangeetaItem Open Access Rapid Screening Methods to Identify Substandard and Falsified Medicines(De Montfort University, 2018-05) Armitage, R.Substandard and falsified medicines (SF) are a major global public health problem and occur throughout healthcare systems worldwide. With an average occurrence of 10% of all medicines globally, the specific levels range from ~1% of all medicines in high-income countries (HIC) to as much as 30-40% in low-income countries (LIC) and low-middle income countries (LMIC). Current detection methods for SF medicines range from ‘low tech’ approaches, for example, visual appearance, thin layer chromatography (TLC) to those that are technically refined, such as, Raman spectroscopy, Near Infrared (NIR) spectroscopy and Mass Spectrometry (MS). In order to counteract the increasing complexity of anti-counterfeit measures, counterfeiters are finding ever more sophisticated ways to bypass existing screening techniques. Therefore, the aim of this research is to develop a novel rapid screening method to identify SF medicines. The performance of seven different benchtop instruments has been investigated with respect to their potential to deliver rapid assessment of the identity and to quantify the level of Active Pharmaceutical Ingredient’s (API’s) present in tablet samples. The materials used in this research comprised of 29 reference samples and 64 individual group samples from 8 countries, totaling some 867 tablets. Tablets were analysed in both whole and powdered forms. Mass Spectrometry provided the least complex data, followed by Raman and then Attenuated Total Reflectance Fourier Transform Infrared (ATR FTIR). The mass spectrometer was the least reliable instrument, but provided the greatest sensitivity. Successful identification of the API was obtained from ATR FTIR and Raman analysis and from Direct Insertion Probe (DIP) Mass Spectrometry. Quantitative levels of API could be obtained from Ultraviolet (UV) and ATR FTIR measurements, whilst some excipient levels could be determined by Elemental Dispersive X-ray (EDX) spectroscopy. Handheld Raman systems produced some erroneous quantitative information. The majority of samples examined were within ±10% of the stated level, as per the British Pharmacopeia specifications; however, there was some evidence of substandard medication. Substandard medication was suspected in 2 of the 64 pharmaceutical products assessed. At the present state of development, the Raman and ATR FTIR equipment could be used in LMIC’s for the screening of tablet samples. PCA in conjunction with Raman spectroscopy identified an anomalous sample in a set of proprietary preparations from different countries. A combination of the techniques cited confirmed the inclusion of a non-standard excipients into this formulation.Item Metadata only Thermodynamic Changes Induced by Intermolecular Interaction Between Ibuprofen and Chitosan: Effect on Crystal Habit, Solubility and In Vitro Release Kinetics of Ibuprofen(Springer, 2015-09-24) Abioye, A. O.; Armitage, R.; Kola-Mustapha, A.Purpose: The direct impact of intermolecular attraction between ibuprofen and chitosan on crystal behaviour, saturated solubility and dissolution efficiency of ibuprofen was investigated in order to expand the drug delivery strategy for ibuprofen. Methods: Amorphous nanoparticle complex (nanoplex) was prepared by controlled drug-polymer nanoassembly. Intermolecular attraction was confirmed with surface tension, conductivity measurements and FTIR spectroscopy. The nanoplex was characterized using DSC, TGA and SEM. The in vitro release kinetics and mechanism of drug release were evaluated using mathematical models. Results: The cmc of ibuprofen decreased significantly in the nanoplex (1.85 mM) compared with pure ibuprofen (177.62 mM) suggesting a remarkable affinity between the chitosan and ibuprofen. The disappearance of ibuprofen melting peak in the nanoplex and the broadened DSC endothermic peaks of the nanoplex indicate formation of eutectic amorphous product which corresponded to higher saturated solubility and dissolution velocity. Ibuprofen (aspect ratio 5.16±1.15) was converted into spherical nanoparticle complex with particle size of 14.96±1.162–143.17±17.5247 nm (36–345 folds reduction)dictated by chitosan concentration. Pure ibuprofen exhibited burst release while the nanoplexes showed both fast and extended release profiles. DE increased to a maximum(81.76± 2.1031%) with chitosan concentrations at 3.28×10–3 g/dm3, beyond which retardation occurred steadily. Major mechanism of drug release from the nanoplex was by diffusion however anomalous transport and super case II transport did occur. Conclusion: Ibuprofen-chitosan nanoplex exhibited combined fast and extended release profile dictated by chitosan concentration.This study demonstrated the potential application of drug-polymer nanoconjugate design in multifunctional regulated drug delivery.