本研究探討以抗菌肽修飾的金奈米粒子用於光熱殺菌的效果。細菌感染的案例在生活中常常看見，例如：皮膚發炎、傷口化膿、糖尿病足等，因此人類對於要怎麼抵抗這些肉眼看不見的微生物是一大挑戰，然而近期抗生素濫用，造成細菌產生了抗藥性，使得抗生素或是其他藥物的治療效果漸漸降低，因此我們使用金奈米粒子作為光能轉換熱能的媒介，並利用接在金奈米粒子表面的抗菌肽增強殺菌效果。抗菌肽除了本身具有殺菌效果，因為它本身的靜電荷，可以主動的附著於細菌表面，並且標記於細胞膜上，整齊排列後產生一個洞口，接在金奈米粒子表面的抗菌肽能使金奈米粒子更容易附著於細菌表面，甚至進入細菌裡使光熱殺菌更有效率，來達到一個使用光與熱的物理性治療。當我們抗菌肽金奈米粒子與細菌反應後，經過雷射光照射，拿去作螢光檢測以及細菌培養來觀察殺菌實驗的效果，並且我們也發展了一套統計方法來證實我們的光熱殺菌是有效且可廣泛使用。由於抗菌肽與細菌間的結合為半專一性，可與多種細菌反映，加上光熱殺菌不受抗藥性的影響，本研究所開發的殺菌技術可望能成有效且廣效性的殺菌治療方式，並且將這種技術更進一步發展成一套細菌檢測系統。

In this study we investigate the efficacy of photothermal therapy (PTT) using antimicrobial peptide-conjugated gold nanoparticles (AMP-AuNPs). In our live, the cases of bacterial infections are often seen, such as skin inflammation, wound fester, diabetic foot, etc. For humans, how to resist these invisible microbes is being a great challenge. However, the bacteria induce resistance because abuse of the antibiotic in recent years, the efficacy of antibiotic or some antimicrobial drugs are reduced gradually. We use AuNPs to convert light into heat, and we use AMPs to enhance the antibacterial effect. AMPs have antibacterial activity because their own electrostatic charge can random insert into the membrane. Next, the AMPs slightly align hydrophobic sequences and remove the membrane sections and form some pores. AMPs can promote the binding between AuNPs and bacteria or even enter the center of bacteria and thus increase the efficacy of photothermal therapy. After the reaction of AMP-conjugated AuNPs and bacteria, the samples expose to laser light and culture the samples on agar plates and stain the bacteria with live/dead cell staining kit to determine whether the bacteria are killed. Given that the binding of AMPs to bacteria is semi-selective and that photothermal therapy is not compromised by antibiotic resistance, we expect the photothermal therapy developed in this study can be an effective and broad-spectrum therapy method and furthermore use this method to achieve a bacterial detection.

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