Abstract

In this work, carbon dots/hydroxyapatite (CD-HAP) nanocomposite has been synthesized and used as drug carrier for acetaminophen. Carbon dots are synthesized from a biowaste precursor, which is sugarcane bagasse char using hydrothermal method. The synthesis of carbon dots is studied under four different temperatures of 150, 170, 190, and 210 °C. The fluorescence behaviour of carbon dots is greatest at an optimum temperature of 190 °C. Carbon dots with the best fluorescence properties are merged with the hydroxyapatite. The transmission electron microscopy (TEM) analysis confirms the formation of spherical nanodots with average diameter of 7.5 nm. The field emission scanning electron microscopy (FESEM) analysis confirms the formation of rod-shaped hydroxyapatite with an average diameter of 142 nm. Elemental analysis shows a Ca/P ratio of 1.71, which is close to Ca/P ratio of 1.67 found in natural bone, indicating the biocompatibility of the nanocomposite. Elemental analysis also shows an increase in carbon weight percentage in CD-HAP when compared with blank HAP, proving the formation of carbon dots in the nanocomposite. The pairing of carbon dots and hydroxyapatite improved the fluorescence of composite greatly, as well as the surface area from 41.631 to 78.752 m²/g. The drug loading and release performance is evaluated by loading acetaminophen into the nanocomposite. CD-HAP-40 gives the highest loading capacity of 48.5%. Acetaminophen release is slower in CD-HAP-20, and the release kinetics fits the Higuchi model. This finding shows that the acetaminophen is released via a diffusion mechanism.

中文翻译：

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生物废物衍生的碳点/羟基磷灰石纳米复合材料作为对乙酰氨基酚的药物输送载体

摘要

在这项工作中，碳点/羟基磷灰石（CD-HAP）纳米复合材料已被合成并用作对乙酰氨基酚的药物载体。碳点是使用水热法从生物废料前体（甘蔗渣炭）合成的。在150、170、190和210°C的四种不同温度下研究了碳点的合成。碳点的荧光行为在190°C的最佳温度下最大。具有最佳荧光特性的碳点与羟基磷灰石融合。透射电子显微镜（TEM）分析证实平均直径为7.5 nm的球形纳米点的形成。场发射扫描电子显微镜（FESEM）分析确认形成了平均直径为142 nm的棒状羟基磷灰石。元素分析表明Ca / P比为1.71，它接近天然骨中发现的Ca / P比1.67，表明该纳米复合材料具有生物相容性。元素分析还显示，与空白HAP相比，CD-HAP中的碳重量百分比增加，证明了纳米复合材料中碳点的形成。碳点和羟基磷灰石的配对极大地改善了复合材料的荧光性，表面积从41.631至78.752 m² /克。通过将对乙酰氨基酚加载到纳米复合材料中来评估药物的加载和释放性能。CD-HAP-40的最高装载量为48.5％。在CD-HAP-20中，对乙酰氨基酚的释放较慢，且释放动力学符合Higuchi模型。该发现表明对乙酰氨基酚是通过扩散机制释放的。