Anzai Kazunori, Aoki Tamami, Koshimizu Satoko, Takaya Reina, Tsuchida Kazunori, Takajo Tokuko
Faculty of Pharmaceutical Sciences, Nihon Pharmaceutical University, 10281 Komuro, Ina-machi, Kitaadachi-gun, Saitama 362-0806, Japan.
J Clin Biochem Nutr. 2019 May;64(3):187-193. doi: 10.3164/jcbn.18-102. Epub 2019 Mar 7.
Because application of cold atmospheric pressure plasma jet (CAPPJ) to biological samples have taken large attentions, it is important to examine the effects of various CAPPJ parameters on the generation of reactive species. Here, we investigated the generation of reactive species in water by CAPPJ irradiation by changing the following parameters: irradiation time, sample volume, and irradiation distance between the sample surface and plasma jet tip. We measured 1) change in the ESR signal intensity of 4-hydroxy-2,2,6,6-tetrametylpeperidine-1-oxyl (Tempol), 2) spin-trapping with 5,5-dimethyl-1-pyrroline -oxide (DMPO), 3) Fricke dosimeter reaction, and 4) hydrogen peroxide (HO) formation induced by CAPPJ irradiation. By the experiment of volume dependency, it is suggested that the reactive species detected in water are formed largely in the plasma gas phase. The reduction of ESR signal intensity of Tempol and the formation of DMPO-OH were strongly dependent on irradiation distance, but the relationship between HO generation and distance was weak. The formation of species that oxidize Fe to Fe was shown by the Fricke dosimeter reaction, and reactions at irradiation distances longer than 3 cm were mainly attributable to HO. It may be possible to apply different reactive species to the samples by changing the CAPPJ irradiation distance.
由于冷大气压等离子体射流（CAPPJ）在生物样品上的应用已受到广泛关注，因此研究各种CAPPJ参数对活性物种生成的影响具有重要意义。在此，我们通过改变以下参数，研究了CAPPJ辐照在水中产生的活性物种：辐照时间、样品体积以及样品表面与等离子体射流尖端之间的辐照距离。我们测量了：1）4-羟基-2,2,6,6-四甲基哌啶-1-氧基（Tempol）的电子自旋共振（ESR）信号强度变化；2）用5,5-二甲基-1-吡咯啉-N-氧化物（DMPO）进行自旋捕获；3）弗里克剂量计反应；4）CAPPJ辐照诱导的过氧化氢（H₂O₂）生成。通过体积依赖性实验表明，水中检测到的活性物种主要在等离子体气相中形成。Tempol的ESR信号强度降低和DMPO-OH的形成强烈依赖于辐照距离，但H₂O₂生成与距离之间的关系较弱。弗里克剂量计反应显示了将Fe氧化为Fe³⁺的物种的形成，且辐照距离大于3 cm时的反应主要归因于H₂O₂。通过改变CAPPJ辐照距离，有可能将不同的活性物种应用于样品。
