Browsing by Author "Tanna, Sangeeta"
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Item Metadata only Adherence to cardiovascular pharmacotherapy assessed by quantitative LC-HRMS analysis of dried blood spots(2016-11-30) Tanna, Sangeeta; Bernieh, Dennis; Lawson, GrahamUp to ~50% of patients prescribed cardiovascular (CVD) drugs do not adhere to their prescribed regimen. Non-adherence impacts on patient health and healthcare system costs. Dried blood spot (DBS) sampling was used to collect micro-volume blood samples for the LC-HRMS quantitative analysis of candidate CVD drugs for objectively assessing adherence to prescribed pharmacotherapy. An LC-HRMS method was used for the quantification of target CVD drugs in DBS samples. The target CVD drugs were solvent extracted from disks punched from DBS and analysed using gradient chromatographic elution with a run time of 2.5 min. MS detection was carried out in electrospray positive ion mode using the precise mass for each target drug. The method was applied to volunteer DBS samples. Drug recoveries from spiked calibration blood spots were ≥82% for all target CVD drugs except for simvastatin at ~57% and the drugs were stable in DBS for at least 12 weeks. Validation of the LC-HRMS method showed good linearity and the accuracy and precision values were within the pre-defined limits of ≤15% at all concentrations. Factors with potential to affect drug quantification measurements such as matrix effects and the volume of blood applied on the collection card were investigated. This bioanalytical method was able to identify and quantify the residual levels of target drugs up to 24 hours after the initial dose. The LC-HRMS DBS based assay successfully identified volunteers who were known to be either adherent or nonadherent.Item Open Access Adherence to cardiovascular pharmacotherapy by patients in Iraq: a mixed methods assessment using quantitative dried blood spot analysis and the 8-item Morisky Medication Adherence Scale(PLOS, 2021-05-14) Alalaqi, Ahmed; Lawson, Graham; Obaid, Yaseen; Tanna, SangeetaThis study evaluated the adherence to prescribed cardiovascular therapy medications among cardiovascular disease patients attending clinics in Misan, Amara, Iraq. Mixed methods were used to assess medication adherence comprising the Arabic version of the eight-item Morisky Medication Adherence Scale (MMAS-8) and determination of drug concentrations in patient dried blood spot (DBS) samples by liquid chromatography-high resolution mass spectrometry. Three hundred and three Iraqi patients (median age 53 years, 50.5% female) who had been taking one or more of the nine commonly prescribed cardiovascular medications (amlodipine, atenolol, atorvastatin, bisoprolol, diltiazem, lisinopril, losartan, simvastatin and valsartan) for at least six months were enrolled. For each patient MMAS-8 scores were determined alongside drug concentrations in their dried blood spot samples. Results from the standardized questionnaire showed that adherence was 81.8% in comparison with 50.8% obtained using the laboratory-based microsample analysis. The agreement between the indirect (MMAS-8) and direct (DBS analysis) assessment approaches to assessing medication adherence showed significantly poor agreement (kappa = 0.28, P=0.001). The indirect and direct assessment approaches showed no significant correlation between nonadherence to prescribed cardiovascular pharmacotherapy and age and gender, but were significantly associated with the number of medications in the patient’s treatment regimen (MMAS-8: Odds Ratio (OR) 1.947, 95% CI, P=0.001; DBS analysis: OR 2.164, 95% CI, P=0.001). The MMAS-8 results highlighted reasons for nonadherence to prescribed cardiovascular pharmacotherapy in this patient population whilst the objective DBS analysis approach gave valuable information about nonadherence to each medication in the patient’s treatment regimen. DBS sampling, due its minimally invasive nature, convenience and ease of transport is a useful alternative matrix to monitor adherence objectively in Iraq to cardiovascular pharmacotherapy. This information combined with MMAS-8 can provide clinicians with an evidence-based novel approach to implement intervention strategies to optimise and personalise cardiovascular pharmacotherapy in the Iraqi population and thereby improve patient health outcomes.Item Metadata only Adherence to cardiovascular pharmcotherapy assessed by quantitative LC-HRMS analysis of dried blood spots(2016-08-24) Tanna, Sangeeta; Bernieh, Dennis; Lawson, GrahamItem Metadata only Adherence to medication assessed using dried blood spot analysis(OMICS, 2014-08-19) Tanna, Sangeeta; Lawson, GrahamItem Open Access Aminobenzofuran-containing analogues of proximicins exhibit higher antiproliferative activity against human UG-87 glioblastoma cells compared to temozolomide(Royal Society of Chemistry, 2023-03-14) Shokrzadeh Madieh, Nasrin; Brucoli, Federico; Tanna, Sangeeta; Alqurayn, Norah Ahmed; Vaideanu, Alexandra; Schatzlein, AndreasA new series of proximicin analogues containing a benzofuran moiety as the replacement of the di-furan scaffold of the parent compound were synthesised and evaluated for their anti-proliferative activities against human glioblastoma cells U-87 MG. Proximicins A, B, and C are secondary metabolites produced by Verrucosispora Fiedleri MG-37, a Gram-positive actinomycete isolated from deep-sea sediment. Proximicins exhibit significant cytotoxic and apoptotic effects in a number of tumour cell lines, although further investigations on these natural products biological activity are hampered by the challenging synthesis of their constitutive di-furan unit. Therefore, the easily-synthesisable benzofuran ring was elected as a replacement of the di-furan platform, and a library of proximicin analogues was prepared in which different substituents were introduced at both the N-terminus and C-terminus of the benzofuran core unit. The novel compounds were tested against U-87 MG, as it was previously found that proximicins targeted this cancerous cell line, and the human healthy cell line WI-38. Temozolomide, the chemotherapeutic agent of choice for the treatment of glioblastoma, was used as a control. Analysis of growth inhibitory concentration values revealed that a number of furan-benzofuran-containing proximicin analogues, including 23(16) (IC50 U-87 MG = 6.54 μg mL−1) exhibited higher antiproliferative activity against glioblastoma cells compared to both proximicins A–C and temozolomide (IC50 U-87 MG = 29.19 μg mL−1) in U-87 MG.Item Metadata only Analysis of dried blood spots - The potential for paediatric pharmakokinetic studies of captopril.(2010-07-26) Tanna, Sangeeta; Mulla, Hussain; Pandya, Hitesh; Titman, C.; Lawson, GrahamItem Metadata only Analytical Chemistry for Assessing Medication Adherence(Elsevier, 2016-04-26) Tanna, Sangeeta; Lawson, GrahamThe lack of adherence to medication is a growing public health problem worldwide and is costing many patients their chance to return to good health and healthcare systems billions of dollars. Analytical Chemistry for Assessing Medication Adherence introduces the concept of assessed medication adherence/compliance and reports international perspectives on medication adherence while highlighting its importance. It then describes the opportunities for analytical chemistry to assess medication adherence and thereby provide an evidence base for clinicians to improve patient health outcomes. The authors highlight the strengths and weaknesses of each of the analytical techniques cited in addition to categorizing the findings in terms of the biosamples used to assess adherence and identifying methods to extract biosamples prior to analysis. The authors capture examples from many countries of the application of bioanalysis to assess medication adherence in a range of chronic conditions and communicable diseases. The final chapter provides the authors’ perspective in this area, emphasizing the importance of medication optimization for individual patients.Item Metadata only Analytical methods used in conjunction with dried blood spots.(Royal Society of Chemistry, 2011-08-12) Tanna, Sangeeta; Lawson, GrahamReview of different analytical methods used to obtain medically related data from dried blood spots. Advantages and limitations of the methodologies are discussed.Item Metadata only Applying dried blood spot analysis: the pathway to better paediatric care.(Pharmaceutical Press, 2009) Patel, Parul; Lawson, Graham; Mulla, Hussain; Tanna, SangeetaItem Metadata only Assessment of liquid captopril formulations used in children.(BMJ, 2010) Mulla, Hussain; Hussain, N.; Tanna, Sangeeta; Lawson, Graham; Manktelow, B. N.; Tuleu, C.; Samani, N. J.; Pandya, HiteshItem Metadata only ATR-FTIR for rapid detection and quantification of counterfeit medicines(Royal Society of Chemistry, 2015-07-03) Ogwu, John; Lawson, Graham; Tanna, SangeetaFrom therapeutic to lifestyle medicines, the counterfeiting of medicines has been on the rise in recent times [1]. Estimates indicate that about 10% of medicines worldwide are counterfeits with much higher figures in developing countries [2]. Currently, the rapid screening of medicines is a challenge leaving many patients at risk [1]. This study considered the potential use of Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) for rapid quantitative analysis of tablet formulations. ATR-FTIR requires minimal sample preparation as it only requires crushing the tablet before analysis unlike the conventional methods where time-consuming solvent extraction of the Active Pharmaceutical Ingredient (API) is necessary. Reference spectra for pure API and excipients were recorded as part of a reference library for identification purposes. Preliminary studies were carried out with tablets having a single API (Paracetamol). API could be identified down to 5% w/w of the tablet. Tablet samples with multiple APIs were also identified. For quantitative analysis, IR spectra of standard mixtures of Paracetamol in excipient were recorded and used in calibration. Paracetamol tablets from Europe, Africa and Southeast Asia were then quantified based on calibration data. Quantification data for selected characteristic peak areas for each API/excipient mixture was linear. Results were in the expected range with conventional UV analysis confirming data obtained. Therefore, ATR-FTIR can be applied in the rapid identification and quantification of tablet formulations. The faster sampling time, simplicity and portability of ATR-FTIR makes it valuable in the authentication of medicines especially in developing countries where facilities are not readily available.Item Open Access Attitudes to weight management in the South Asian population(Springer, 2019-03) Robinson-Burke, Tamara; Tanna, Sangeeta; Hind, James; Fretwell, Laurice; Williams, Robert; Sutton, Christopher; Dunford, L. J.Item Metadata only Bisoprolol, ramipril and simvastatin determination in dried blood spot samples using LC-HRMS for assessing medication adherence.(Elsevier, 2013-05-07) Lawson, Graham; Cocks, Elizabeth; Tanna, SangeetaItem Metadata only Blood spot micro-samples analysed by LC-HRMS to monitor cardiovascular drug levels in patient samples from Iraq.(2017-12-07) Tanna, Sangeeta; Alalaqi, Ahmed; Bernieh, Dennis; Obaid, Yaseen; Lawson, GrahamItem Metadata only Can quantitative dried blood spot analyses be an aid to medicine optimization in cardiovascular diseases?(Royal Society of Chemistry, 2015-07-03) Bernieh, Dennis; Lawson, Graham; Tanna, SangeetaIntroduction: Over 355 million prescriptions were dispensed for cardiovascular diseases in the UK in 2013 [1]. Half of these, costing the NHS £2.3 billion, were wasted because patients do not take their medicines as prescribed [2]. A method using dried blood spot (DBS) sample collection followed by liquid chromatography-high resolution mass spectrometry (LC-HRMS) [3] was developed and validated for quantification of eleven commonly UK prescribed cardiovascular drugs: amlodipine, atenolol, atorvastatin, bisoprolol, diltiazem, doxazosin, lisinopril, losartan, ramipril, simvastatin and valsartan. Thus medication efficiency, adherence or drug/drug interactions can be assessed from reference pharmacokinetic data. Methods: For the preparation of DBS calibration samples whole blood was spiked with eleven target analytes to produce 30µl blood spots on specimen cards. 8mm disc was punched out and extracted with methanol:water (70:30v/v) containing the internal standard, atenolol D7. Chromatography analysis was performed using gradient elution with a run time of 2.5 min. MS detection was carried out in electrospray positive ion mode for all target analytes and internal standard. Results: The LC-HRMS method showed good linearity and the accuracy (relative error) and precision (coefficient of variation) values were within the pre-defined limits of ≤15% at all tested concentrations for eight of the target drugs. Drug recoveries from spiked blood spots were ≥ 82% for atenolol, bisoprolol, diltiazem, doxazosin, losartan, ramipril and valsartan. Results from volunteers were within expected levels except where elevated levels indicated a recognised drug/drug interaction. Conclusions: Quantitative DBS analyses can be used as a means to optimize medication for heart disease patients.Item Metadata only Captopril Determination in Dried Blood Spot Samples with LC-MS and LCHRMS: A Potential Method for Neonate Pharmacokinetic Studies(OMICS, 2012-03-07) Lawson, Graham; Mulla, Hussain; Tanna, SangeetaThe use of blood spot collection cards was investigated as a means of obtaining small volume samples for the analysis of therapeutic drugs for the purpose of neonatal pharmacokinetic studies. We describe the development of two micro-analytical methods for the determination of captopril extracted from dried blood spots (DBS). Firstly a liquid chromatography ion-trap mass spectrometry method with selected ion monitoring (LC-MS(SIM)) of target ion at m/z 218.0 was developed to determine captopril levels in 8mm discs punched from each DBS. This was compared in terms of specificity and sensitivity to a simple accurate mass liquid chromatography high resolution TOF mass spectrometry (LC-HRMS) method in which MS detection was carried out in electrospray positive ion mode for target ions at m/z 218.0845 for captopril and 377.2084 for the IS. Dithiothreitol was used both to pre-treat the sampling cards and as part of the extraction medium in order to stabilise the DBS extracted captopril. Drug extraction efficiency from spiked blood spots was demonstrated to be 90 ± 10% and the drug was stable in DBS for at least 12 weeks. Validation of both micro-analytical methods showed good precision and accuracy and the LC-HRMS method was linear within the tested calibration range 10-400ng/ml for captopril and had improved sensitivity and specificity compared to the LC-MS(SIM) method. This method was applied to blood spots on sampling card from a neonate patient previously administered 1mg/kg captopril orally. The amount of captopril in the DBS was 88ng/ml. Requiring only a micro volume (30µl) blood sample for analysis, the developed DBS based micro-analytical method has the potential to facilitate pharmacokinetic studies of captopril in children.Item Metadata only Cardiovascular Drug Medication Adherence Assessed by Dried Blood Spot Analysis(OMICS, 2014-01) Tanna, Sangeeta; Lawson, GrahamThe use of dried blood spot (DBS) collection cards was investigated for the detection of therapeutic drugs used in cardiovascular therapy for assessing medication adherence. A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed for the determination of, bisoprolol, ramipril, and simvastatin. Whole blood spiked with target analytes was used to produce 30 μl blood spots on specimen collection cards for calibration purposes. An 8 mm disc was cut from the dried blood spot and extracted using methanol: water (70:30, v/v). The High Resolution MS detection, at the precise mass of the target drugs, was carried out in electrospray positive ion mode. The LC-HRMS method successfully identified control volunteers who were known to be either adherent or non-adherent. There were no false positives from volunteers taking other cardiovascular drugs or from volunteers receiving no medication. Potentially therefore the system would identify non–adherent patients based on the absence of the target analyte in the DBS sample provided.Item Metadata only Cardiovascular drug medication compliance assessed by dried blood spot sampling techniques(OMICS, 2013-10) Tanna, Sangeeta; Lawson, GrahamItem Metadata only Cardiovascular drug monitoring using quantitative LC-HRMS analysis of self-collected micro-volume blood samples(2017-09-24) Tanna, Sangeeta; Bernieh, Dennis; Alalaqi, Ahmed; Lawson, GrahamBackground Evidence suggests that ˃50% of cardiovascular (CVD) disease patients do not adhere to treatment thus impacting on patient health, additional healthcare costs and medicines wastage. DBS microsampling combined with LC-ToF MS detection has the potential to offer a simple means to monitor drug levels to enable clinicians to personalise optimum treatment for patients. This research compared the use of Whatman 903 dried blood spot (DBS) sample collection cards with volumetric absorptive micro-sampling (VAMS)/Mitra® technology for use as a personal sampling methodology. Methods Recruited volunteers were given demonstrations and information sheets concerning the investigation and sample collection. A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was validated for the determination of the top 11 UK prescribed cardiovascular drugs. For the preparation of DBS and VAMS calibration samples whole blood was spiked with different levels of the 11 target analytes. 8mm DBS discs or the absorptive VAMS tips were extracted with methanol containing the internal standard. The bioanalytical method was applied to fingerprick samples taken from volunteers some of whom were prescribed one or more of the target drugs. Volunteers not prescribed drugs represented blank samples. Results Approximately 17% of the DBS spots were unacceptable for quantification whereas 1 VAMS sample tip was rejected due to incomplete collection. Validation showed comparable quantitative results between the DBS and VAMS microsampling methods for the 11 target drugs. For two study groups anticipated cardiovascular drugs were detected in 83% of the pre-warned group and 73% of the trial group. The latter figure was higher than expected possibly due to the ‘white coat compliance’. The detected drug levels were in line with literature values for the half-life and Cmax for a given drug, Non-adherence was not uniform amongst the cardiovascular drugs. All volunteers preferred the VAMS methodology. Conclusions Both microsampling methods coupled with LC-HRMS analyses facilitate the identification of patients where the prescription apparently failed to produce detectable drug levels in the blood. This information should inform clinicians how to proceed in the healthcare process in the event of poor patient progress.Item Metadata only Closed-loop delivery of insulin.(Adis International, 2004) Taylor, M. Joan; Tanna, Sangeeta; Sahota, T. S.