背景:环糊精是一种公认的体系,与许多客体分子形成包合复合物。这种性质可以容易地用于开发药物递送系统。此外,碳点(CD)是低毒性的光致发光产物,其已被用作发光标签。环糊精和碳点的组合可以获得新的纳米平台,一种生物相容性材料,有了这两种能力,增加CD细胞的内在化,由环糊精诱导。
结果:在目前的工作中,我们用β和γ环糊精修饰了从柠檬酸和谷胱甘肽获得的碳点的表面。经过形态学和光谱学表征,我们得出的结论是,衍生的和未修饰的碳点的发光量子产率和吸收摩尔系数是相同的。这些发现,结合活性环糊精的光谱检测,那些与CD结合的能够与客体分子相互作用的物质,允许测定比率:环糊精/CD,活性环糊精/CD和CD分子质量的估计。此外,新材料的生物相容性通过细胞毒性和细胞穿透率测定进行评估,发现材料无细胞毒性高达0.1mg/mL。此外,生物相容性开发的纳米平台穿透细胞维持材料的固有荧光,因此构成了一个足够的光致发光标签,具有高对比度的体外细胞成像。
结论:这项工作提供了一种将环糊精和碳点结合到生物相容性材料中的新方法,该材料可用作纳米平台,既可用作药物递送系统,也可用作细胞成像中的光致发光标签。同样,本文介绍了如何表征每个CD的环糊精和活性环糊精的数量,客体分子-CD的平均化学计量比为1:1。此外,间接获得未修饰CD的最小分子量,产量约1.6-1.9kDa。
BACKGROUND: Cyclodextrins are a well-established system which form inclusion complexes with many guest molecules. This property can be easily exploited to develop drug delivery systems. Additionally, carbon dots (CD) are a low-toxic photoluminescent product which have been used as luminescent tags. The combination of
cyclodextrins and carbon dots allows obtaining a new nanoplatform, a biocompatible material, with both capabilities, increasing as well the internalization by the cells of the CD, induced by the cyclodextrins.
RESULTS: In the present work, we have modified the surface of carbon dots obtained from citric acid and glutathione with β and γ cyclodextrins. After a morphological and spectroscopic characterization, we concluded that the luminescence quantum yield and absorption molar coefficient of the derivatized and unmodified carbon dots was the same. These findings, together with the spectroscopic detection of active
cyclodextrins, those bond to the CD able to interact with a guest molecule, allowed determination of the ratios: cyclodextrins/CD, active
cyclodextrins/CD and an estimation of the CD molecular mass. Furthermore, the biocompatibility of the new materials was evaluated through cytotoxicity and cell-penetrance assays revealing that the materials were non cytotoxic up to 0.1 mg/mL. Moreover, the biocompatible developed nanoplatform penetrates in the cells maintaining the material\'s intrinsic fluorescence, thus constituting an adequate photoluminescent-tag with high-contrast for in vitro cell imaging.
CONCLUSIONS: This work provides a new and easy method to combine cyclodextrins and carbon dots into a biocompatible material which can be used as nanoplatform both as drug delivery system and as photoluminescent tag in cell imaging. Likewise, this paper shows how to characterize the number of
cyclodextrins and active
cyclodextrins per CD, having an average stoichiometric relation of 1:1 for guest molecule - CD. Additionally, the minimum molecular mass of the unmodified CD was indirectly obtained, yielding about 1.6-1.9 kDa.