Baltch A L, Smith R P, Franke M A, Ritz W J, Michelsen P, Bopp L H, Singh J K
Infectious Disease Section and Laboratory Medicine, Stratton VA Medical Center and Albany Medical College, New York 12208, USA.
Am J Infect Control. 2000 Jun;28(3):251-7. doi: 10.1067/mic.2000.105287.
MDI-P (Medical Discoveries, Inc-Pharmaceutical, Layton, Utah) is a clear, colorless liquid generated by electrolysis of preservative-free and endotoxin-free, nonpyrogenic, sterile, injection saline (0.9% NaCl, wt/vol). It contains numerous highly reactive chlorine and oxygen species, including HOCl(-1,) OCl-(1), Cl(-1), Cl(2), O(2-)(1), and O(3). This report presents data on the in vitro microbicidal activity of MDI-P against 4 clinically relevant microbial pathogens that are often difficult to eradicate.
MDI-P was generated from injection saline by using a patented electrolysis instrument. It was then tested for microbicidal activity at concentrations ranging from 0.01% to 50% against Staphylococcus aureus, Pseudomonas aeruginosa, Legionella pneumophila, and Candida albicans (10(5) to 10(9) colony-forming units/mL). The effect of serum (50% and 90%) and pH on MDI-P activity were also tested. The morphologic effects of MDI-P on microbial cells were studied by light microscopy of cells stained by Gram's method and by transmission electron microscopy. Morbidity, mortality, and the effect of MDI-P on tissues were studied by using a mouse model.
The microbicidal activity of MDI-P occurred within the first minute of exposure for all the organisms tested. When 50% MDI-P was tested against cell titers of 10(5) or 10(7) colony-forming units/mL, all test organisms were killed within 1 minute; at lower MDI-P concentrations, C albicans was the most sensitive organism, and L pneumophila was the most resistant. Even with beginning cell titers of 10(9) colony-forming units/mL, killing by 50% MDI-P was >99.9% for all test strains. Furthermore, at the same beginning cell titer, killing of C albicans by MDI-P diluted to 50% with normal human serum rather than injection saline was only slightly reduced. No acute morbidity, mortality, or tissue damage was detected in mice that were intravenously given 17 mL/kg of undiluted MDI-P.
MDI-P is a very fast-acting, broad-spectrum microbicidal material. The lack of evidence for acute morbidity, mortality, or tissue injury, ease of preparation, and low cost suggest that it may be useful for various sterilization and disinfection applications.
MDI - P（Medical Discoveries, Inc - Pharmaceutical，犹他州莱顿）是一种清澈、无色的液体，通过对无防腐剂、无内毒素、无热原、无菌的注射用生理盐水（0.9% NaCl，重量/体积）进行电解产生。它含有多种高活性的氯和氧物质，包括次氯酸（HOCl(-1)）、次氯酸根离子（OCl-(1)）、氯离子（Cl(-1)）、氯气（Cl(2)）、超氧阴离子（O(2-)(1)）和臭氧（O(3)）。本报告展示了MDI - P对4种临床相关且通常难以根除的微生物病原体的体外杀菌活性数据。
使用专利电解仪器从注射用生理盐水中生成MDI - P。然后在浓度范围为0.01%至50%的条件下，测试其对金黄色葡萄球菌、铜绿假单胞菌、嗜肺军团菌和白色念珠菌（10(5)至10(9)菌落形成单位/毫升）的杀菌活性。还测试了血清（50%和90%）以及pH对MDI - P活性的影响。通过革兰氏染色法对细胞进行光学显微镜观察以及透射电子显微镜观察，研究MDI - P对微生物细胞的形态学影响。使用小鼠模型研究MDI - P的发病率、死亡率及其对组织的影响。
对于所有测试的生物体，MDI - P的杀菌活性在暴露的第一分钟内就出现了。当用50%的MDI - P测试10(5)或10(7)菌落形成单位/毫升的细胞滴度时，所有测试生物体在1分钟内被杀死；在较低的MDI - P浓度下，白色念珠菌是最敏感的生物体，嗜肺军团菌是最耐药的。即使起始细胞滴度为10(9)菌落形成单位/毫升，50%的MDI - P对所有测试菌株的杀灭率也>99.9%。此外，在相同的起始细胞滴度下，用正常人血清而非注射用生理盐水稀释至50%的MDI - P对白色念珠菌的杀灭作用仅略有降低。静脉注射17毫升/千克未稀释的MDI - P的小鼠未检测到急性发病率、死亡率或组织损伤。
MDI - P是一种作用非常迅速的广谱杀菌材料。缺乏急性发病率、死亡率或组织损伤的证据，易于制备且成本低，这表明它可能对各种消毒灭菌应用有用。
