Raw data: Leaching ratio (μg/g) of mercury from Tibetan medicine Zuotai,β-HgS and α-HgS in different pH solutions

Zuotai, a known Tibetan medicinal mixture containing insoluble cubic mercuric sulfide (β-HgS), has been used to treat diseases with long history. The mercury leaching ratio from Zuotai in gastrointestinal pH environment is one determinant factor for its bioavailability and biological effect. However, the information is still scarce now. Therefore, the study was designed to investigate the mercury leaching from Zuotai, β-HgS, and α-HgS in different pH solutionsSolutions with different pH values (1–13) were prepared from pure water, HCl solution, and NaOH solution; the pH was monitored using a pH meter. The solutions were as follows: HCl solution with pH = 1, HCl solution with pH = 3, HCl solution with pH = 5, NaOH solution with pH = 7, NaOH solution with pH = 9, NaOH solution with pH = 11, and NaOH solution with pH = 13. A solid-liquid ratio of 1:100 was adopted in all leaching experiments. Digestion, peristalsis and emptying of drug in the gastrointestinal tract were simulated in vitro. We detected the mercury released in solutions using Automatic Direct Mercury Analyzer. Leaching Ratio of Mercury (μg/g)=[Total Weight of Mercury Released (μg)]/[Total Weight of Substance Tested (g)]The results showed that the mercury leaching ratios of Zuotai at pH 1 and pH 13 were significantly higher than those at each point within pH 3–11; the mercury leaching ratio of Zuotai at pH 1 was higher than that at pH 13. The mercury leaching ratio of β-HgS slightly decreased from pH 1 to pH 3 and significantly increased from pH 3 to pH 13. The mercury leaching ratio of β-HgS at pH 13 was far higher than that at pH 1. For α-HgS, the mercury leaching ratio also slightly decreased from pH 1 to pH 3 and then gradually increased from pH 3 to pH 13. The mercury leaching ratio of α-HgS at pH 1 was lower than that at pH 13. Taken together, strong acidic or strong alkaline environments would promote the dissociation of mercury from Zuotai, β-HgS, and α-HgS.

佐太（Zuotai）是一种经典藏药复方，其成分包含不溶性立方晶型硫化汞（β-HgS），拥有悠久的疾病治疗历史。胃肠道pH环境下佐太中汞的溶出率，是影响其生物利用度与生物学效应的关键决定因素之一，但目前相关研究数据仍较为匮乏。为此，本研究旨在探究佐太、β-HgS与α-HgS在不同pH溶液中的汞溶出特性。本实验采用纯水、盐酸溶液与氢氧化钠溶液配制pH值范围为1~13的系列溶液，使用pH计实时监测溶液pH值。所配制的溶液具体如下：pH=1盐酸溶液、pH=3盐酸溶液、pH=5盐酸溶液、pH=7氢氧化钠溶液、pH=9氢氧化钠溶液、pH=11氢氧化钠溶液以及pH=13氢氧化钠溶液。所有溶出实验均采用1:100的固液比，并体外模拟了药物在胃肠道内的消化、蠕动与排空过程。采用全自动直接测汞仪对溶液中释放的汞进行定量检测，汞溶出率（μg/g）的计算公式为：汞溶出率=释放汞总质量（μg）/受试物质总质量（g）。实验结果显示：佐太在pH=1与pH=13条件下的汞溶出率，均显著高于pH3~11范围内各pH条件下的溶出率；且佐太在pH=1时的汞溶出率高于pH=13时的水平。β-HgS的汞溶出率在pH1至pH3区间内略有下降，而在pH3至pH13区间内显著升高；其在pH=13时的汞溶出率远高于pH=1时的水平。α-HgS的汞溶出率同样在pH1至pH3区间内略有下降，随后在pH3至pH13区间内逐步升高；其在pH=1时的汞溶出率低于pH=13时的水平。综上，强酸性或强碱性环境均可促进佐太、β-HgS与α-HgS中汞的解离溶出。