Hook G R, Elin R J, Hosseini J M, Swyt C, Fiori C E
J Microsc. 1986 Jan;141(Pt 1):69-78. doi: 10.1111/j.1365-2818.1986.tb02701.x.
We present a sample preparation method for measuring magnesium in individual whole lymphocytes by electron probe X-ray microanalysis. We use Burkitt's lymphoma cells in culture as the test sample and compare X-ray microanalysis of individual cells with atomic absorption analysis of pooled cell populations. We determine the magnesium peak-to-local continuum X-ray intensity ratio by electron probe X-ray microanalysis and calculate a mean cell magnesium concentration of 39 +/- 19 mmol/kg dry weight from analysis of 100 cells. We determine a mean cell magnesium concentration of 34 +/- 4 mmol/kg dry weight by atomic absorption analysis of pooled cells in three cell cultures. The mean cell magnesium concentrations determined by the two methods are not significantly different. We find a 10% coefficient of variation for both methods of analysis and a 30% coefficient of variation in magnesium concentration among individual cells by electron probe X-ray microanalysis. We wash cells in ammonium nitrate for microanalysis or in buffered saline glucose for atomic absorption analysis. We find cells washed in either solution have the same cell viability (85%), recovery (75%), cell volume (555 microns 3) and cytology. We air dry cells on thin film supports and show by magnesium X-ray mapping that magnesium is within the cells. We conclude that: our microanalysis cell preparation method preserves whole intact lymphocytes; there is no systematic difference in results from the two methods of analysis; electron probe X-ray microanalysis can determine the variation in magnesium concentration among individual cells.
我们介绍了一种通过电子探针X射线微分析法测量单个全淋巴细胞中镁含量的样品制备方法。我们使用培养的伯基特淋巴瘤细胞作为测试样品，并将单个细胞的X射线微分析结果与汇集细胞群体的原子吸收分析结果进行比较。我们通过电子探针X射线微分析法测定镁的峰对局部连续X射线强度比，并通过对100个细胞的分析计算出平均细胞镁浓度为39±19 mmol/kg干重。我们通过对三种细胞培养物中汇集细胞的原子吸收分析，确定平均细胞镁浓度为34±4 mmol/kg干重。两种方法测定的平均细胞镁浓度无显著差异。我们发现两种分析方法的变异系数均为10%，通过电子探针X射线微分析法测定单个细胞间镁浓度的变异系数为30%。我们用硝酸铵洗涤细胞用于微分析，或用缓冲盐水葡萄糖洗涤细胞用于原子吸收分析。我们发现用这两种溶液洗涤的细胞具有相同的细胞活力（85%）、回收率（75%）、细胞体积（555立方微米）和细胞学特征。我们将细胞在薄膜支持物上空气干燥，并通过镁X射线映射显示镁在细胞内。我们得出结论：我们的微分析细胞制备方法能保存完整的全淋巴细胞；两种分析方法的结果没有系统差异；电子探针X射线微分析法可以确定单个细胞间镁浓度的变化。
