Protective film-forming disinfectant based on chitosan/water/ethanol tertiary solutions

项目摘要 新型冠状病毒（SARS-CoV-2）已成为现代世界最大的挑战之一， 在地球仪造成了数百万人感染和数十万人死亡的大流行。 通过呼吸道飞沫以及受污染的手和环境传播 表面。因此，潜在污染表面的清洁和消毒成为最重要的问题之一。 沿着社交距离和手部卫生，是预防冠状病毒传播的重要措施。 目前CDC预防冠状病毒传播的指南特别建议清洁和 经常接触的表面消毒。 使用市售消毒剂可显著减少环境表面上的微生物数量 仅在治疗后4小时内。一种具有能够形成抗微生物剂的化合物的醇基消毒剂， 耐用但可去除的生物杀灭膜可以联合收割机结合上述两种方法的优点。它将 联合收割机结合了由于酒精的存在而产生的高短期功效和防止由于 膜的持久功效，同时需要较不频繁的应用。 VRM实验室最近开发了这样的消毒剂，其含有3 wt. %的壳聚糖和60%wt.乙醇 壳聚糖是从甲壳类动物壳中获得的，其抗微生物和抗病毒功效是公认的。 然而，由于其水溶液的高粘度， 形成连续薄膜所需的干燥时间长。我们提出的配方具有低粘度， 成膜性能和干燥时间与目前使用的消毒剂相似。在初步研究中， 用这种新配方处理的手柄在处理后可防止微生物生长长达48小时。 该I期研究的目标是创建基于壳聚糖的消毒剂的优化原型，并测试其 杀菌和杀病毒性能在一个有限规模的研究，在医疗机构。在目标I中，我们将描述 成膜性能，包括膜厚度、膜耐久性、耐磨性和膜干燥时间 用不同的壳聚糖和乙醇浓度配制。我们还将评估体外抗菌和 这些基于壳聚糖的涂层与最常见的病原体的抗病毒功效已知是 环境表面上的感染源，并与替代冠状病毒模拟抗病毒作用， 新冠肺炎。在目标II中，我们将使用目标I中开发的优化配方来涂覆几个指定的电梯 按钮，门把手，和床栏杆在医疗设施（格林维尔纪念医院在南卡罗来纳州）。我们 然后将定期从这些涂层表面收集环境拭子，并比较微生物 和病毒计数与根据当前医院方案处理的类似表面获得的那些相比。这些 实验将有助于确定涂层的功效时间窗。

Project Summary A novel coronavirus (SARS-CoV-2) has become one of the greatest challenges of the modern world and has caused a pandemic with millions of infected people and hundreds of thousands of deaths around the globe. Transmissions occur through respiratory droplets, as well as through contaminated hands and environmental surfaces. Therefore, cleaning and disinfection of potentially contaminated surfaces becomes one of the most important measures in prevention of coronavirus transmission, along with social distancing and hand hygiene. Current CDC guidelines for preventing transmission of coronavirus specifically recommend cleaning and disinfection of frequently touched surfaces. The use of commercially available disinfectants significantly reduces microbial counts on environmental surfaces for only up to 4 hours after treatment. An alcohol-based disinfectant with a compound capable of forming a durable but removable biocidal film could combine the advantages of both approaches described above. It would combine high short-term efficacy due to the presence of alcohol and prevent microbial re-contamination due to the long-lasting efficacy of the film, while requiring less frequent applications. VRM Labs has recently developed such disinfectant, which contains 3 wt. % chitosan and 60 % wt. ethanol. Chitosan is obtained from crustacean shells and its antimicrobial and antiviral efficacy is well-established. However, it has not been used in surface disinfectants because of high viscosity of its aqueous solutions and long drying times required to form a continuous film. Our proposed formulation has low viscosity, outstanding film-forming properties and drying time similar to that for currently used disinfectants. In preliminary studies, door handles treated by this novel formulation prevented microbial growth for up to 48 hours after treatment. The goal of this Phase I study is to create an optimized prototype of chitosan-based disinfectant and to test its bactericidal and viricidal performance in a limited-scale study in a healthcare setting. In Aim I, we will characterize film formation properties, including film thickness, film durability, abrasion resistance, and film drying times for formulations with different chitosan and ethanol concentrations. We will also evaluate in vitro antimicrobial and antiviral efficacy of these chitosan-based coatings with the most common pathogens involved known to be a source of infection on environmental surfaces, and with a surrogate coronavirus to mimic antiviral action against COVID-19. In Aim II, we will use the optimized formulation developed in Aim I to coat several designated elevator buttons, door handles, and bed rails in a medical facility (Greenville Memorial Hospital in South Carolina). We will then collect environmental swabs from these coated surfaces on a regular basis and compare the microbial and viral counts to those obtained from similar surfaces treated according to the current hospital protocol. These experiments will help to determine the efficacy time window for the coating.