當下，許多常壓非熱電漿以13.56 MHz之射頻作為其激發頻率，有關改變頻率對於非熱微電漿系統之影響的研究相對較少。考慮到常壓下氣體密度遠大於低壓或真空環境，理論上激發電漿可以使用更低的激發頻率。因此，本文使用兩種不同的頻率，分別為100 kHz和1 MHz，作為所開發之新型非熱微電漿系統的激發頻率，該微電漿系統以氮氣和氦氣作為激發氣體，採用微型化的新設計。降低頻率後可減少電源功耗並節省裝置所需的體積，但此低頻電漿之實際效用仍有待研究。因此，透過對其電漿特性的評估和比較，本文探討了這兩種微電漿的物理特性和於細胞處理上的應用效果，並對不同頻率之微電漿的差異進行了比較。
在符合德國DIN法規之要求下，結合對活性物種及電漿激發效率的考量，最終選定此新型微電漿較佳使用參數如下。100 kHz微電漿使用功率僅為1.6 W，而1 MHz之微電漿使用功率僅為4.9 W，兩者均有著良好的能量使用效率。此外，以2 SLM的氦氣為主激發氣體，添加1% 之氮氣作第二氣體，工作操作距離定為 8 mm。在使用上述參數的情況下，1 MHz微電漿相較於100 kHz 之微電漿有著更多解離的電子，通過光譜分析證實其對氦氣有著較高的激發效率。但在電漿火炬達到相近之溫度且工作距離相同的條件下，100 kHz之微電漿系統所使用的電功率更低。於細胞應用上，兩種不同頻率的非熱微電漿皆可有效提升纖維母細胞的增殖速度。細胞的MTS活性經電漿處理且培養24小時後有顯著性地增加(p<0.05)。100 kHz之微電漿在處理時間為10秒時，細胞經電漿處理後MTS活性較未處理之細胞提升的幅度最大，平均增加了近1.58倍；而1 MHz之微電漿則在處理時間為15秒時提升的幅度最大，平均增加了近1.56倍。此外，纖維母細胞內ROS的含量在經電漿處理後亦有顯著性地提升(p<0.05)。100 kHz和1 MHz之微電漿在處理時間為15秒時，細胞內ROS含量較未處理之細胞提升的效果分別為1.26和1.28倍。但在細胞遷移能力方面，使用上述微電漿在處理時間為5, 10和15秒的情況下，均未能顯著提升小鼠纖維母細胞的遷移效果。同時，小鼠纖維母細胞FGF7的釋放水平在電漿處理後未有顯著地提高。

In this paper, two different frequencies, 100 kHz and 1 MHz were used as the excitation frequencies of a new non-thermal micro-plasma system (GPSR). The system uses nitrogen and helium as excitation gases and adopts a new miniaturized design. Compared with traditional RF plasma, reducing the frequency can reduce the power consumption and save the volume of the device, but the practical utility of these low-frequency plasma needs to be investigated. The power of 100 kHz micro-plasma is only 1.6 W, while the power of 1 MHz micro-plasma is only 4.9 W. In addition, 2 SLM helium is used as the main excitation gas, and 1% nitrogen is added as the second gas. The working distance is set as 8 mm. Using the above parameters, Spectral analysis shows that 1 MHz micro-plasma has higher excitation efficiency for helium. However, the power used by the 100 kHz micro-plasma system is lower to reach the same temperature. In cell application, 100 kHz and 1 MHz micro-plasma can significantly improve the proliferation of fibroblasts. In particular, the OD value of MTS activity of cells treated for 10 s and 15 s increased by around 1.5 times compared with that of untreated cells after 24 hours incubation. However, 100 kHz and 1 MHz micro-plasma did not significantly promote the migration ability of fibroblast cells at the plasma treatment dose of 5, 10 and 15 seconds.

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