當傷口於30天內顯少或沒有癒合的徵象，則被定義為慢性傷口（Chronic Wounds）。當病人本身具有潛在疾病根原，容易延遲癒合機制並形成慢性傷口，目前發生比例更隨著老年人口、糖尿病或其他慢性疾病病患人口的增加而逐年攀升，使慢性傷口對於全球醫療照護上的影響甚鉅。
細菌膜感染是目前慢性傷口上常見的問題之一，根據研究顯示約有六成的慢性傷口表面有細菌膜的生長，其所生成的外圍基質提供微生物良好的生長環境並影響宿主的免疫反應，此外因細菌膜對於抗生素的抗藥性較高，對於慢性傷口的治療上造成極大的困擾，故判斷傷口上是否有細菌膜的生成為一迫切的問題。
有鑒於現今細菌膜的檢測方法較為耗時及複雜，本研究建立一套化學染色法，針對細菌膜基質中的成分-多醣體作為檢測目標，利用具生物相容性之帶正電荷的尼龍轉印膜來採集傷口檢體，再以具專一性的Alcian Blue進行染色，最後藉由比色法來判斷是否有細菌膜的生成。本研究以慢性傷口感染上常見的菌種：金黃色葡萄球菌及綠膿桿菌此兩株菌作為in-vitro model，來探討染色條件的最佳化，結果顯示以5%的十六烷基三甲基氯化銨（CTAC）陽離子界面活性劑作為Blocking及Wash試劑，有助於降低背景訊號干擾來提高判斷的精準性。此外我們收取15組臨床傷口檢體進行染色方法的驗證，實驗結果顯示本研究的Alcian Blue染色法與細菌培養法具有8成的一致性，且此染色方法可在數分鐘內完成，我們期此方法能提供臨床、居家照護上一個簡易、非侵入式且快速的重點照護方法，以提升慢性傷口的照護品質。

Wounds without the normal healing phases (i.e., more than 30 days) have been defined as chronic wounds. How to deal with the chronic wounds has become one of the major worldwide healthcare issues since the elder population is growing. The chronic wounds, such as pressure ulcers, diabetic foot ulcers as well as venous ulcers, have been common problems among elder patients with chronic diseases (e.g., diabetics). During the past decade, the clinical-based evidence has been recognized the bacterial infection as one of the important factors for both the diagnosis and treatment of chronic wounds.

Recent studies have indicated that 60% of the chronic wound has been characterized to mainly contain the biofilm versus 6% of the acute wound. The biofilm has been identified as the co-growth community with multiple types of bacteria that is built off the extra polymeric matrix to support the exchange of nutrients and wastes. Such a community naturally prefer to attach the specific surface such as wound beds – chronic wounds later on. More importantly, the biofilm (containing several types of bacteria) shows the better resistance to the commonly-use antibiotics associated with the host immune responses. The biofilm-based wound therapy therefore has been extensively addressed. However, before the healthcare persons determine the precise treatment plan to deal with the wounds, one of the critical issues is to diagnose whether the biofilm has been formed onto the wound beds – what we would like to focus in this study.

In this study, we have established a colorimetric-based approach with the characteristics of the simplicity, inexpensiveness and time-saving, allowing us to quickly detect the biofilm on the wound beds – an emergency issue in multiple divisions of medicine. Unlike the conventional bacteria culture method, we used the biofilm extracellular matrix, which contains polysaccharides, to detect whether the biofilm exists onto the wound bed. We chose the S. aureus and P. aeruginosa, which are the most common type of infection bacteria in chronic wounds, to build up the in-vitro model to optimize our staining protocol. The experiment showed that using Nylon transfer membrane with the positive charged to collect the sample and 5% Cetyl trimethyl ammonium chloride (CTAC) as the blocking and washing solution has a better performance to decrease the noise. Finally, we collect the 15 clinical wound tissue samples to verify our staining protocol. It showed the 80% of consistency with the tissue culture method and the whole staining procedure can be done in few minutes. We believe, this study, could provide a practical point-of-care approach with a good sensitivity for clinical use to deal with this longstanding medicine issue.

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