Lao-Oxford-Mahosot Hospital-Wellcome Research Unit (LOMWRU), Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao PDR.
Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
Sci Rep. 2024 Feb 18;14(1):3995. doi: 10.1038/s41598-024-54168-9.
We explored whether isotope ratio mass spectrometry (IRMS) is useful to investigate the origin of falsified antimalarials. Forty-four falsified and genuine antimalarial samples (artesunate, artemether-lumefantrine, dihydroartemisinin-piperaquine and sulphamethopyrazine-pyrimethamine) were analyzed in bulk for carbon (C), nitrogen (N), and oxygen (O) element concentrations and stable isotope ratios. The insoluble fraction ("starch") was extracted from 26 samples and analyzed. Samples of known geographical origin maize, a common source of excipient starch, were used to produce a comparison dataset to predict starch source. In both an initial (n = 18) and a follow-on set of samples that contained/claimed to contain artesunate/artemether (n = 26), falsified antimalarials had a range of C concentrations less than genuine comparator antimalarials and δC values higher than genuine comparators. The δC values of falsified antimalarials suggested that C plant-based organic material (e.g., starch derived from maize) had been included. Using the known-origin maize samples, predictions for growth water δO values for the extracted "starch" ranged from - 6.10 to - 1.62‰. These findings suggest that IRMS may be a useful tool for profiling falsified antimalarials. We found that C ingredients were exclusively used in falsified antimalarials versus genuine antimalarials, and that it may be possible to predict potential growth water δO values for the starch present in falsified antimalarials.
我们探讨了同位素比质谱（IRMS）是否可用于研究伪造抗疟药物的来源。对 44 种伪造和真品抗疟药物样本（青蒿琥酯、青蒿琥酯-甲氟喹、双氢青蒿素-哌喹和磺胺多辛-乙胺嘧啶）进行了批量分析，以测定碳（C）、氮（N）和氧（O）元素浓度和稳定同位素比值。从 26 个样本中提取了不溶性部分（“淀粉”）并进行了分析。使用已知地理来源的玉米（一种常见的赋形剂淀粉来源）的样本，生成了一个比较数据集，以预测淀粉来源。在最初的（n=18）和后续的包含/声称包含青蒿琥酯/甲氟喹的样本（n=26）中，伪造的抗疟药物的 C 浓度范围小于真品对照药物，δC 值高于真品对照药物。伪造抗疟药物的 δC 值表明，已包含植物源 C 有机物质（例如，源自玉米的淀粉）。使用已知来源的玉米样本，提取的“淀粉”生长水 δO 值的预测范围为-6.10 至-1.62‰。这些发现表明，IRMS 可能是一种用于分析伪造抗疟药物的有用工具。我们发现，伪造抗疟药物仅使用 C 成分，而真品抗疟药物则不使用，而且可能有可能预测伪造抗疟药物中淀粉的潜在生长水 δO 值。
