Abstract：
Folic acid (FA) is easily photodegraded to yield 6-formylpterin and pterin-6-carboxylic acid, which can generate reactive oxygen species and result in the formation of oxidized guanine derivatives such as 8-hydroxy-2\'-deoxyguanosine and 8-hydroxy-guanosine. In this study, we developed a simple, rapid, and sensitive liquid chromatography-tandem mass spectrometry strategy for the simultaneous determination of FA photolysis products and oxidized guanine derivatives in plasma samples. Chromatographic separation was performed on a Waters HSS T3 column (2.1 × 100 mm, 5.0 μm) with gradient elution at a flow rate of 0.25 mL/min. Plasma samples were first pretreated with 1% formic acid, followed by protein precipitation with methanol. The developed method showed good linear relationships between 1 and 2000 ng/mL (r2 > 0.99). The intra- and inter-day precisions ranged from 2.6% to 7.5% and from 2.5% to 6.5%, respectively. Recoveries of the analytes were between 75.4% and 112.4% with the relative standard deviation < 9.1%. Finally, the method was applied to quantify FA photolysis products and oxidized guanine derivatives in rats with light and non-light conditions.
摘要：
叶酸（FA）很容易光降解，产生6-甲酰蝶呤和蝶呤-6-羧酸，可产生活性氧并导致形成氧化的鸟嘌呤衍生物，如8-羟基-2'-脱氧鸟苷和8-羟基-鸟苷。在这项研究中,我们开发了一个简单的，快速,和灵敏的液相色谱-串联质谱策略，用于同时测定血浆样品中的FA光解产物和氧化的鸟嘌呤衍生物。色谱分离在WatersHSST3柱(2.1×100mm,5.0μm），以0.25mL/min的流速进行梯度洗脱。血浆样品首先用1%甲酸预处理,然后用甲醇沉淀蛋白质。所开发的方法在1和2000ng/mL之间显示出良好的线性关系（r2>0.99）。日内和日间精确度范围从2.6%到7.5%，从2.5%到6.5%，分别。分析物的回收率在75.4%和112.4%之间,相对标准偏差<9.1%。最后,该方法用于在光照和非光照条件下定量大鼠的FA光解产物和氧化的鸟嘌呤衍生物。
