Browsing by Author "Rashani, S. A. N."

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Development of an lc-ms/ms method for the detection of prednisolone doping using human fingernails
(Postgraduate Institute of Science (PGIS) , University of Peradeniya, 2024-11) Kanishka, W. A. S.; Fernando, P. N. J.; Rashani, S. A. N.; Jayakody, R. S.; Cooray, A.; De Silva, A. P.
Sports doping detection mainly relies on urine and blood samples. Nails are less commonly used, even though they can provide long-term drug use, due to challenges in preparation and pulverization. This study developed a Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) method to detect prednisolone in human fingernails. Nails from volunteers not administered with prednisolone were ethically collected, cleaned, dried, and pulverized for analysis. The extraction of prednisolone was optimized for solvent type, extraction frequency, and shaking rate. The optimized sample preparation was followed by cleaning of Nail clippings by vortexing at 2200 rpm using ultrapure water at 50 °C for 75 secs, drying at 50 °C for 80 mins, cutting into small pieces, and subjected to methanol extraction by shaking for 18 hrs at 300 rpm. LC-MS/MS analysis used a biphenyl column (100 mm × 2.1 mm, 2.7 μm) with a binary gradient of acidified (0.1% formic acid) acetonitrile and an aqueous phase to identify prednisolone. The run time for the LC-MS/MS method was 7.50 minutes. The retention time of prednisolone was 2.18 minutes. The method was validated according to International Council for Harmonization (ICH) guidelines, showing strong linearity (R² > 0.99) and high specificity with no carryover. Within-run accuracy and precision were ± 3.24% and 3.76% coefficient of variation (CV), respectively, while between-run accuracy and precision were ± 4.18% and 3.5% CV, respectively. LOD and LOQ were 0.0003 mg/L and 0.00154 mg/L, respectively. Using a cost-effective pulverization setup, the validated The LC-MS/MS method effectively detected prednisolone in fingernails. Further studies with prednisolone-doped nails are needed to advance nail-based doping detection in sports and forensics.
Method validation for the detection of undeclared Furosemide drug contaminations in herbal weight loss supplements using LC-MS/MS
(Faculty of Science, University of Kelaniya Sri Lanka, 2024) Ranasinghe, R. M. S. T. B.; Cooray, A. T.; Rashani, S. A. N.; De Silva, A.; Fernando, P. N.
Numerous herbal weight loss supplements are widely consumed globally; however, there is a general concern regarding undeclared synthetic substances. Furosemide (4-chloro-2-(furan-2-ylmethylamino)- 5-sulfamoylbenzoic acid) is a potent diuretic substance, and it is prohibited for athletes due its ability to mask the presence of performance enhancing drugs in urine and its ability for rapid weight loss by excreted water as urine. This study aims to validate a new method for the detection of undeclared furosemide in weight loss supplements available in the local market using LC-MS/MS. In developing the method validation protocol, after testing the recovery and the matrix effect for suitability, two different herbal weight loss supplements were pulverised and mixed to make the blank matrix. Then 100.0 mg of the mixture was introduced to a centrifuge tube and 10.0 mL acetonitrile (LC/MS grade) was added to it, and sonicated for 10 minutes. The resultant solution was centrifuged for 10 minutes at 5000 rpm and the supernatant was double diluted and filtered using nylon filters (0.22μm). Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction was used for coloured extractants. Seventeen (17) commercially available weight loss supplements were purchased from local retailers and analysed for the presence of furosemide using the developed method. In the developed method, a 1:1 ACN:Water mobile phase, biphenyl column operating at 40°C, 0.2 sec loop time was used. Under these conditions, the retention time of furosemide is 3.82 minutes. The developed method was validated according to the ICH (M10 2022) and Eurachem guidelines (second edition 2014). The linearity (r2 = 0.99) of the calibration plot, selectivity, LOD (0.14 nmol m-3) and LOQ (0.48 nmol m-3), trueness (±15%), precision (±5%), recovery (70.96%-81.06%) and matrix effects (103.0%-107.1%) were determined to ensure the method's validity for the intended purpose. None of the supplements contained detectable furosemide levels using the validated LC/MS/MS method. The absence of detectable furosemide in the analysed samples suggests that the tested supplements may not be adulterated with this specific diuretic or it is below the detection limit of this method.
Screening for prednisolone in anti-asthmatic herbal remedies using lc-ms/ms in sri lanka.
(Postgraduate Institute of Science (PGIS), University of Peradeniya, 2024-11) Fernando, S. S. D.; Fernando, P. N. J.; Rashani, S. A. N.; Cooray, A.; De Silva, A. P.
Prednisolone, a corticosteroid used to treat asthma, poses significant concerns when adulterated in herbal remedies, particularly for athletes subjected to anti-doping regulations. Despite their widespread use, comprehensive studies to determine the extent of prednisolone adulteration in herbal products are lacking in Sri Lanka. This study aimed to fill this research gap by screening commonly used herbal remedies for asthma in Sri Lanka to identify the presence of Prednisolone. A tailored LC-MS/MS method was developed and validated for this purpose. An optimized ultrasound-assisted extraction procedure was established using a reference standard, achieving a recovery rate of 100.45% by adjusting the extraction solvent and sonication time. The LC-MS/MS method utilised a biphenyl column (100 mm × 2.1 mm, 2.7 μm) with a mobile phase of acetonitrile and water acidified with 0.1% formic acid. Chromatographic conditions were optimized for a column; oven temperature of 50 °C, an initial acetonitrile concentration of 5%, a dwell time of 0.200 secs, and a run time of 10 min. Validation of the method followed EuraChem guidelines and was done using a Prednisolone reference standard, demonstrating high precision, accuracy, sensitivity, and specificity. Extraction recoveries showed relative standard deviation (%RSD) ≤ 10% and calibration linearities had R2 ≥ 0.988. The detection limits were 0.03 μg/g for powdered and 0.003 μg/mL for liquid herbal matrices. The study screened 27 different over-the-counter brands and prescription anti-asthmatic herbal products collected randomly from suburban areas of Colombo. The validated LC-MS/MS method identified that 25 products were below the detection limit, while two prescribed products were flagged as doubtful. In conclusion, the developed LC-MS/MS method successfully detected prednisolone in complex herbal matrices with high specificity and precision, providing valuable insights into the prevalence and extent of prednisolone adulteration in herbal remedies.