Development of a New Pin-point Treatment of Cancer Cells Using Hydrogen Storage Alloy as Hydrogen Supplier

为了开发一种针尖治疗癌细胞的方法，研究了储氢合金的放氢行为以及不同合金成分和样品形状的储氢合金放氢对生物细胞的影响。所获得的结果总结如下。1)气态氢和氢离子的数量以及氢自由基随合金成分的不同而变化。因此，可以通过调整合金成分来控制放氢行为。2)从细胞存活概率(POS)的测量中观察到癌细胞和部分正常细胞的POS降低，发现放氢的影响与细胞的种类有关。3)在样品外约2~2.5 mm处可观察到选择性的癌细胞死亡，与样品形状无关。4)从ESR实验和荧光试剂对过氧化氢的检测中，检测到氢自由基、羟基自由基和过氧化氢，提示这些氢物种对癌细胞的死亡有影响。

To develop a pin-point treatment of cancer cells, hydrogen discharging behavior of hydrogen storage alloy(HSA) and the effect of hydrogen discharged from the HSA with different alloy composition and sample shape on biological cells have been studied. The results obtained are summarized as follows. 1) The amount of gaseous hydrogen and hydrogen ions as well as hydrogen radicals varied depending upon alloy composition. It is, therefore, possible to control the hydrogen discharging behavior by adjusting the alloy composition. 2) From the observation of the probability-of-survival(POS) measurement, a reduction in the POS was observed in cancer cells and a part of normal cell, and it was found that the influence of discharged hydrogen depends on the kind of cells. 3) A selective cancer cell death was observed in the region of approximately 2~ 2. 5 mm outside the samples, independent of sample shape. 4) From the ESR experiment and the detection of hydrogen peroxide using fluorescent regent, hydrogen radical, hydroxyl radical and hydrogen peroxide were detected and it was suggested that these hydrogen species would affect to cancer cell death.