Anti-mold, heat transfer characteristics and vacuum degree of medical bamboo fire cup after anti-mold treatment

Bamboo fire cup (BFC) is popularly physical therapy instruments in traditional Chinese medicine with its good biodegradability, biocompatibility in acupuncture and moxibustion therapy. Limited research on the influence of BFC size on heat transfer performance, vacuum retention efficacy during cupping and easy mold infection have restricted its large – scale application. Thus, this study applied a combined treatment of slightly acidic electrolyzed water (SAEW) impregnation and surface paraffin coating to create a novel BFC with three different sizes, aiming to understand the above problems. The anti-mold effect of BFC was evaluated by surface bacterial counts and mold infection levels after 28 days. The radial density profile and thermal conductivity of the BFC wall were tested. A simulated cupping procedure was conducted to analyze the temperature field, cooling rate, and vacuum stability of the BFC during the cupping process. BFC treated with SAEW and paraffin coating exhibited satisfied mold resistance with surface bacterial counts reduced by over 90 % and a mold grade of 0. Paraffin coating lightly increased the outer surface density of the BFC wall while enhancing thermal conductivity by 10 %. The BFC showed obvious temperature loss at cup bottom and thermal insulation at cup body resulting in a slow decline of temperature. Wax treatment showed a 50 % improvement in vacuum retention capacity of BFC. This is conducive to reducing the heat loss of patients during the cupping therapy process. This study provided a novel BFC with excellent anti-mold, thermal and vacuum stability and it is expected to further expand its application in acupuncture and traditional medicine. • Bamboo fire cup (BFC) was treated by slightly acidic electrolyzed water and paraffin. • Outer surface density of treated BFC increased with good insulation performance. • Treatment group reduced surface bacteria by over 90 % and achieved a mold level of 0. • BFC mainly lost heat through the bottom, while the cup body primarily retained heat. • Treated BFC for vacuum degree increased by 50 % with pressure fluctuation below 120 mmHg.