The lucrative market of herbal remedies spurs rampant adulteration, particularly with pharmaceutical drugs and their unapproved analogues. A comprehensive screening strategy is, therefore, warranted to detect these adulterants and, accordingly, to safeguard public health. This study uses the data-dependent acquisition of liquid chromatography-quadrupole time-of-flight–mass spectrometry (LC–QTOF–MS) to screen phosphodiesterase 5 (PDE5) inhibitors in herbal remedies using suspected-target and non-targeted strategies. For the suspected-target screening, we used a library comprising 95 PDE5 inhibitors. For the non-targeted screening, we adopted top-down and bottom-up approaches to flag novel PDE5 inhibitor analogues based on common fragmentation patterns. LC–QTOF–MS was optimised and validated for capsule and tablet dosage forms using 23 target analytes, selected to represent different groups of PDE5 inhibitors. The method exhibited excellent specificity and linearity with limit of detection and limit of quantification of <40 and 80 ng/mL, respectively. The accuracy ranged from 79.0% to 124.7% with a precision of <14.9% relative standard deviation. The modified, quick, easy, cheap, effective, rugged, and safe extraction provided insignificant matrix effect within −9.1%–8.0% and satisfactory extraction recovery of 71.5%–105.8%. These strategies were used to screen 52 herbal remedy samples that claimed to enhance male sexual performance. The suspected-target screening resulted in 33 positive samples, revealing 10 target analytes and 2 suspected analytes. Systematic MS and tandem MS interrogations using the non-targeted screening returned insignificant signals, indicating the absence of potentially novel analogues. The target analytes were quantified from 0.03 to 121.31 mg per dose of each sample. The proposed strategies ensure that all PDE5 inhibitors are comprehensively screened, providing a useful tool to curb the widespread adulteration of herbal remedies.

中文翻译：

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使用液相色谱-四极杆飞行时间-质谱法对草药中磷酸二酯酶 5 抑制剂的疑似靶标和非靶标筛选

利润丰厚的草药市场刺激了猖獗的掺假，尤其是药物及其未经批准的类似物。因此，有必要采取全面的筛查策略来检测这些掺假物，从而保护公众健康。本研究使用液相色谱-四极杆飞行时间质谱 (LC-QTOF-MS) 的数据依赖采集技术，使用疑似靶向和非靶向策略筛选草药中的磷酸二酯酶 5 (PDE5) 抑制剂。对于可疑目标筛选，我们使用了一个包含 95 个 PDE5 抑制剂的库。对于非靶向筛选，我们采用自上而下和自下而上的方法来标记基于常见碎片模式的新型 PDE5 抑制剂类似物。LC-QTOF-MS 使用 23 种目标分析物针对胶囊剂和片剂剂型进行了优化和验证，这些目标分析物被选为代表不同组的 PDE5 抑制剂。该方法表现出优异的特异性和线性，检测限和定量限分别为 <40 和 80 ng/mL。准确度范围为 79.0% 至 124.7%，相对标准偏差<14.9%。改进的、快速、简单、廉价、有效、坚固和安全的提取提供了-9.1%–8.0% 内不显着的基质效应和 71.5%–105.8% 的令人满意的提取回收率。这些策略用于筛选 52 种声称可以增强男性性能力的草药样品。疑似目标筛查结果为 33 个阳性样本，揭示了 10 个目标分析物和 2 个疑似分析物。使用非靶向筛选的系统 MS 和串联 MS 询问返回微不足道的信号，表明不存在潜在的新型类似物。目标分析物的定量范围为每个样品的每剂 0.03 至 121.31 mg。提议的策略确保对所有 PDE5 抑制剂进行全面筛选，为遏制草药的广泛掺假提供了有用的工具。