天然冰片在小鼠组织内的GC—MS测定法和组织分布研究

目的：建立天然冰片在小鼠组织内含量测定的GC—MS法并进行组织分布研究，初步探索天然冰片的归经特征。方法：采用DB-5MS弹性毛细管色谱柱（0．25mm×30m×0．25μm）；电子轰击（E1）电离方式，轰击能量为70eV，倍增电压1100V；选择性离子检测（SIM），天然冰片m／z95，内标萘m／z128；小鼠组织样品用生理盐水匀浆后，加入萘作为内标，用正己烷振荡萃取，取上清液进样测定。组织分布研究以天然冰片的CMC—Na溶液给小鼠灌胃，在不同时间点分批处死小鼠后取各组织样本，经处理后用GC—MS法测定组织中的天然冰片含量。结果：本研究建立的天然冰片GC—MS测定方法，在22ng·mL^-1 -22μg·mL^-1范围内响应信号（Y）与天然冰片浓度（X）呈良好线性关系，Y=0．000486X＋0．00036，R^2=0．999（n=3），最低检测限为10ng·mL^-1，定量下限为22ng·mL^-1，日内精密度为3．72—6．11％，日间精密度为7．29～17．6％，相对回收率和提取回收率分别为85．95～107．93％和93．04～103．03％。组织分布研究结果表明，天然冰片分布于大部分组织，单个组织内天然冰片浓度随时间延长呈现多峰现象；天然冰片在肝脏内含量最高，在心、脑、肾等重要组织内的含量也较高。结论：本研究建立的GC—MS测定方法准确、可靠，可用于天然冰片在动物体内的定量分析；天然冰片在不同组织内的分布有明显差异，肝、肾、心、脑中分布含量较高；天然冰片的归经特征中有归心经的趋势。

A Novel GC-MS Bioanalytical Method for Natural Borneol and Its Application in Investigating Natural Borneol Distribution in Mice

One of the major goals of our group is to understand the meridian tropism of natural borneol. As the first step, this study served two purposes： to develop a GC-MS bioanalytical method for natural bomeol, and with the aid of this method to investigate natural borneol distribution in mice. Mouse tissue samples, spiked with naphthalene as the internal standard, were homogcnated with NS and extracted using hexane. The extract supernatant was analyzed in GC-MS with conditions of DB-5MS capillary column （0.25mm×30m×0.25μm）, electron impact （EI） ionization with energy of 70eV and multiplier voltage of 1100V, and the Selected Ion Monitor （SIM） detection mode. The calibration curve was linear in the range from 22ng· mL^-1 to 22μg·mL^-1 with a regression equation Y= 0.000486X ＋ 0.00036, R^2= 0.999. The limit of detection was 10ng. mL-1. The lower limit of quantitation was 22ng· mL^-1. The within-day and inter-day precisions were 3.72%-6.11% and 7.29%-17.6%, respectively. The relative recovery was 87.8%-103.2% and the extraction recovery 93.04%-103.03%. This bioanalytical method has sufficient recovery and is accurate and reliable for quantitating natural borneol in tissues. The tissue distribution up to 150min after a single oral dose of natural bomeol was investigated in mice. This compound was detected in most tissues. The liver had the highest concentration, followed by kidney, heart, brain, and others. Tissue concentration-time curves had double or triple peaks. The tissue distribution pattern suggested that natural borneol may attribute to the cardio-system.