**7. Conclusion**

**6. Clinic trials and biosafety concern**

132 Plasma Medicine - Concepts and Clinical Applications

Beside animal studies, clinical trials have also been done on patients, especially by using several commercialized products. The world's first plasma source used for clinical trials was the microwave plasma torch MicroPlaSter. Using the first-generation product named MicroPlaSter α, they treated 38 chronic infected wounds on 36 patients with 291 5-min daily treatments and standard wound care, and obtained a significant reduction (34%) of bacterial load without any side effects [90]. In the following study, they compared plasma treatment on various etiologies (Group A), all chronic ulcers (Group B) and Group C for 5-min plasma treatment of chronic venous ulcers. They found a greater reduction in width and length in Group A than control. In Groups B and C, significant reduction in width was found with plasma treatment but not in length [91]. **Figure 8** shows a modified version of MicroPlaSter β and results of treating inflamed ulcer [92]. Isbary et al. reported a successful treatment of

**Figure 8.** Inflamed ulcer of the right lower leg treatment with cold atmospheric argon plasma generated by MicroPlaSter

β [92].

Atmospheric pressure cold plasmas could affect different stages of wound healing by helping to activate microorganisms in the first stage and stimulate skin-related cell proliferation and migration in the following period. CAPs have demonstrated high wound healing abilities and may become a promising therapy to replace or assist traditional methods in clinics for wound healing process, especially in chronic wounds. With the certification of several CAP products, more standards and procedures for clinical treatments should be cleared in the future to guide the plasma treatment under an effective and safe way.
