Gretchen Tibbits¹ | Abdelrhman Mohamed¹ | Suzanne Gelston¹ | Laure Flurin² | Yash S. Raval² | Kerryl E. Greenwood‐Quaintance² | Robin Patel^2,3 | Haluk Beyenal¹

Abstract

The activity of a hypochlorous acid‐producing electrochemical bandage (e‐bandage) in preventing methicillin‐resistant Staphylococcus aureus infection (MRSA) infection and removing biofilms formed by MRSA was assessed using a porcine explant biofilm model. e‐Bandages inhibited S. aureus infection (p = 0.029) after 12 h (h) of exposure and reduced 3‐day biofilm viable cell counts after 6, 12, and 24 h exposures (p = 0.029). Needle‐type microelectrodes were used to assess HOCl concentrations in explant tissue as a result of e‐bandage treatment; toxicity associated with e‐bandage treatment was evaluated. HOCl concentrations in infected and uninfected explant tissue varied between 30 and 80 µM, decreasing with increasing distance from the e‐bandage. Eukaryotic cell viability was reduced by an average of 71% and 65% in fresh and day 3‐old explants, respectively, when compared to explants exposed to nonpolarized e‐bandages. HOCl e‐bandages are a promising technology that can be further developed as an antibiotic‐free treatment for wound biofilm infections.

KEYWORDS

biofilms, chronic wounds, electrochemical bandage, hypochlorous acid, MRSA, Staphylococcus aureus

梁金正 1 ，邵欣欣 2 ，杜少华 1 ，戴双武 1

文题释义：

次氯酸：化学式HClO，是氯气溶解于水时形成的一种一价氯的含氧弱酸。在工业上，次氯酸作为家用漂白剂和清洁剂中的活性成分而广为人知。在生物学系统中，次氯酸可被视为白细胞例如中性粒细胞和单核细胞产生的毒性最强、丰度最高的氧化剂。

细菌生物膜：也称为生物被膜，是指附着于有生命或无生命物体表面被细菌胞外大分子包裹的有组织的细菌群体，存在各种主要的生物大分子如蛋白质、多糖、DNA、RNA、肽聚糖、脂和磷脂等物质。细菌生物膜多细胞结构的形成是一个动态过程，包括细菌起始黏附、细菌生物膜发展和成熟扩散等阶段。细菌生物膜对抗生素和宿主免疫防御机制的抗性很强。

摘要

背景：骨科内固定物感染中形成的细菌生物膜是临床非常棘手的问题。次氯酸作为一种高效消毒剂，可引起细菌生物膜破坏，可能对骨科内固定物感染治疗有帮助。

目的：研究次氯酸溶液体外浸泡不同时间及灌注对骨科内固定物表面细菌生物膜的清除作用。

方法：将金黄色葡萄球菌和铜绿假单胞菌分别在骨科钢板内固定物上定植3 d后形成细菌生物膜，扫描电镜下确认细菌生物膜已形成。采用次氯酸溶液分别浸泡已形成两种细菌生物膜的内固定物0，5，10，20 min及20 min+灌注6 L次氯酸和生理盐水的混合溶液(每3 L生理盐水加入120 mL次氯酸)，扫描电镜下观察细菌生物膜形态，评估次氯酸溶液对内固定物细菌生物膜的清除效果。

结果与结论：①铜绿假单胞菌：扫描电镜下可见，未经次氯酸溶液浸泡的内固定物上的细菌生物膜斑块面积大且较厚，菌落密集集中；经过次氯酸浸泡5，10，20 min后，细菌生物膜斑块面积逐渐减小并变薄，次氯酸溶液浸泡20 min+灌注6 L次氯酸和生理盐水的混合溶液可清除细菌生物膜；②金黄色葡萄球菌：扫描电镜下的表现与铜绿假单胞菌生物膜一致；③结果表明：延长浸泡时间或联合灌注可增强次氯酸对内固定物细菌生物膜的清除作用；次氯酸溶液浸泡足够时长可降解破坏内固定物上定植的细菌生物膜，清除菌落，从而达到消毒目的。

关键词：次氯酸；细菌生物膜；骨科手术；骨科内固定物；感染；消毒剂

¹南方医科大学第三附属医院骨科医学中心骨肿瘤科，广东省广州市 510630； ²中山大学附属第一医院麻醉科，广东省广州市 510080

第一作者：梁金正，男，1994 年生，广东省云浮市人，汉族，骨科住培医师，主要从事骨感染等方面研究。

通讯作者：戴双武，在读博士，主治医师，南方医科大学第三附属医院骨科医学中心骨肿瘤科，广东省广州市 510630 https://orcid.org/0000-0001-6824-5950 ( 梁金正 )

基金资助：广东省科技计划项目 (2020A1414050028)，项目负责人：戴双武

引用本文：梁金正，邵欣欣，杜少华，戴双武 . 次氯酸对骨科内固定物表面细菌生物膜的清除作用 [J]. 中国组织工程研究， 2022，26(15):2367-2371.

Liang Jinzheng1 , Shao Xinxin2 , Du Shaohua1 , Dai Shuangwu1

¹Department of Musculoskeletal Oncology, Center for Orthopedic Surgery, the Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, Guangdong Province, China; ² Department of Anesthesiology, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080, Guangdong Province, China Liang Jinzheng, Resident of the Center for Orthopedic Surgery, the Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, Guangdong Province, China

Corresponding author: Dai Shuangwu, MD candidate, Attending physician, Department of Musculoskeletal Oncology, Center for Orthopedic Surgery, the Third Affiliated Hospital of Southern Medical University, Guangzhou 510630, Guangdong Province, China

Abstract

BACKGROUND: Biofilm formation during the infection of orthopedic fixation devices is a very difficult clinical problem. Hypochlorous acid, as a highly effective disinfectant, can destroy the bacterial biofilm, which may be helpful for treating infection of orthopedic fixation devices.

OBJECTIVE: To study the scavenging effect of hypochlorous acid on bacterial biofilm on the surface of orthopedic fixation devices after soaking and perfusion for different time in vitro.

METHODS: Staphylococcus aureus and Pseudomonas aeruginosa were colonized on orthopedic steel fixation devices for 3 days, and then the bacterial biofilm formed, which was confirmed by scanning electron microscope. Orthopedic fixation devices with two kinds of bacterial biofilms were soaked in hypochlorous acid for 0, 5, 10, and 20 minutes, or perfused with 6 L of a mixed solution of hypochlorous acid and saline (every 3 L of saline with addition of 120 mL of hypochlorous acid) for 20 minutes. The morphology of bacterial biofilms was observed under scanning electron microscope, and the scavenging effect on the bacterial biofilm on the surface of orthopedic internal fixation devices was then evaluated.

RESULTS AND CONCLUSION: Pseudomonas aeruginosa: Under the scanning electron microscope, the bacterial biofilm plaques on the surface of the internal fixation device that was not soaked in hypochlorous acid solution were large and thick, and the colonies were densely concentrated. After 5, 10, and 20 minutes soaking in hypochlorous acid, the bacterial biofilm plaque area was gradually decreased and became thinner. Perfusion with 6 L of a mixture of hypochlorous acid and saline for 20 minutes could remove the bacterial biofilm. Staphylococcus aureus: The performance under the scanning electron microscope was  consistent with the biofilm of Pseudomonas aeruginosa. To conclude, prolonging the soaking time or a mixed perfusion can enhance the scavenging effect of hypochlorous acid on the bacterial biofilm on the surface of internal fixation devices. By soaking in hypochlorous acid for a sufficient time, the bacterial biofilm colonized on the surface of orthopedic internal fixation devices can be degraded and destroyed, thus achieving the purpose of disinfection.

Key words: hypochlorous acid; bacterial biofilm; orthopedic surgery; orthopedic internal fixation device; infection; disinfectant

Esteban Padulles-Gaspar ¹ , Esteban Padulles-Roig ² , Guillermo Cabanes ² , Román A. Pérez ³ , Javier Gil ^3,* and Begoña M. Bosch ^3,*

¹Facultad de Odontología, Universitat Internacional de Catalunya, C/Josep Trueta s/n, 08195 Barcelona, Spain

²Department of Implantology, University of La Salle, Madrid, EDE, C7Gaminedes 11, 28023 Madrid, Spain

³Bioengineering Institute of Technology, Universitat Internacional de Catalunya, 08195 Barcelona, Spain

^*Correspondence: 该Email地址已收到反垃圾邮件插件保护。要显示它您需要在浏览器中启用JavaScript。 (J.G.); 该Email地址已收到反垃圾邮件插件保护。要显示它您需要在浏览器中启用JavaScript。 (B.M.B.)

Abstract: One of the main problems in oral implantology today is peri-implantitis, which affects almost 20% of dental implants placed in patients. One of the most commonly used techniques to eliminate bacterial biofilm is the implantoplasty, that consists of the mechanical modification of the implant surface topography followed by treatments with chemical reagents for decontamination. In this study, the main aim is to evaluate the use of two different chemical treatments based on hypochlorous acid (HClO) and hydrogen peroxide (H2O2 ). For this purpose, 75 titanium grade 3 discs were treated with implantoplasty according to established protocols. Twenty-five discs were used as controls, 25 were treated with concentrated HClO and 25 were treated with concentrated HClO followed by treatment with 6% H2O2 . The roughness of the discs was determined using the interferometric process. Cytotoxicity with SaOs-2 osteoblastic cells was quantified at 24 and 72 h, whereas bacteria proliferation using S. gordonii and S. oralis bacteria was quantified at 5 s and 1 min of treatment. The results showed an increase in the roughness values, the control discs had an Ra of 0.33 µm and those treated with HClO and H2O2 reached 0.68 µm. Cytotoxicity was present at 72 h, together with a significant proliferation of bacteria. These biological and microbiological results can be attributed to the roughness produced by the chemical agents that triggered bacterial adsorption while inhibiting osteoblast adhesion. The results indicate that even if this treatment can decontaminate the titanium surface after implantation, the produced topography will generate an environment that will not favor long-term performance.

Keywords: hypochlorous acid; hydrogen peroxide; implantoplasty; periimplantitis

Chun-Ju Chen ¹ , Chun-Cheng Chen ^2,3,* and Shinn-Jyh Ding ^1,2,3,*

¹Institute of Oral Science, Chung Shan Medical University, Taichung City 402, Taiwan; 该Email地址已收到反垃圾邮件插件保护。要显示它您需要在浏览器中启用JavaScript。

²School of Dentistry, Chung Shan Medical University, Taichung City 402, Taiwan

³Department of Dentistry, Chung Shan Medical University Hospital, Taichung City 402, Taiwan

^*Correspondence: 该Email地址已收到反垃圾邮件插件保护。要显示它您需要在浏览器中启用JavaScript。 (C.-C.C.); 该Email地址已收到反垃圾邮件插件保护。要显示它您需要在浏览器中启用JavaScript。 (S.-J.D.);

Tel.: +886-6-2471-8668 (ext. 55255) (C.-C.C.); +886-6-2471-8668 (ext. 55529) (S.-J.D.)

Academic Editor: Ihtesham ur Rehman

Received: 13 April 2016; Accepted: 15 July 2016; Published: 19 July 2016

Abstract: Chemotherapeutic agents have been used as an adjunct to mechanical debridement for peri-implantitis treatment. The present in vitro study evaluated and compared the effectiveness of hypochlorous acid (HOCl), sodium hypochlorite (NaOCl), and chlorhexidine (CHX) at eliminating Gram-negative (E. coli and P. gingivalis) and Gram-positive (E. faecalis and S. sanguinis) bacteria. The effect of irrigating volume and exposure time on the antimicrobial efficacy of HOCl was evaluated, and a durability analysis was completed. Live/dead staining, morphology observation, alamarBlue assay, and lipopolysaccharide (LPS) detection were examined on grit-blasted and biofilm-contaminated titanium alloy discs after treatment with the three chemotherapeutic agents. The results indicated that HOCl exhibited better antibacterial efficacy with increasing irrigating volumes. HOCl achieved greater antibacterial efficacy as treatment time was increased. A decrease in antimicrobial effectiveness was observed when HOCl was unsealed and left in contact with the air. All the irrigants showed antibacterial activity and killed the majority of bacteria on the titanium alloy surfaces of biofilm-contaminated implants. Moreover, HOCl significantly lowered the LPS concentration of P. gingivalis when compared with NaOCl and CHX. Thus, a HOCl antiseptic may be effective for cleaning biofilm-contaminated implant surfaces.

Keywords: dental implant; hypochlorite acid; antiseptics; antimicrobial activity