A new approach to extracting substances from a spot on a chromatographic plate for subsequent liquid chromatography-mass spectrometry analysis is described. This method involves extraction in a solid phase (an adsorbent layer of a chromatographic plate) - a liquid system using a simple device. For a single extraction of six selected coccidiostats from the adsorbent layer on the chromatographic plate with silica gel, 50 µL of methanol was used for 5 min. The data from the extraction experiments and liquid chromatography-mass spectrometry measurements demonstrated a good correlation between the ratio of the peak areas of the coccidiostats to the internal standard and the concentration of the substances in the range of two orders of magnitude. The coefficients of determination for the mentioned correlations range from 0.962 to 0.999. Moreover, the repeatability and reproducibility, expressed as the percentage values of relative standard deviation, do not exceed 7.5 % for any of the coccidiostats.

中文翻译：

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从色谱板吸附剂层中的点进行固液微萃取的方法

描述了一种从色谱板上的点中提取物质以进行后续液相色谱-质谱分析的新方法。该方法涉及使用简单装置在固相（色谱板的吸附剂层）-液体系统中进行萃取。为了用硅胶从色谱板上的吸附剂层中单次提取六种选定的球虫抑制剂，使用 50 µL 甲醇 5 分钟。提取实验和液相色谱-质谱测量数据表明，抗球虫药与内标物的峰面积比与物质浓度在两个数量级范围内具有良好的相关性。上述相关性的决定系数范围为 0.962 至 0.999。此外，任何球虫抑制剂的重复性和再现性（以相对标准偏差的百分比值表示）均不超过 7.5%。