无溶剂法荧光碳点的制备及卵巢癌细胞荧光成像研究

目的：构建基于碳点（carbon dots，CDs）的荧光纳米探针CDs@Tf，探讨其材料制备及应用于卵巢癌细胞荧光成像的潜能。方法：以二水合柠檬酸钠和尿素为原料，在高温下经无溶剂法制备一种高效荧光碳点，用新型四唑化合物（MTS）法检测其对人卵巢癌细胞HO?8910及人脐静脉血管内皮细胞EA.hy926的细胞毒性。昆明小鼠经尾静脉注射CDs 7 d和21 d后采集主要器官（心、肺、肾、肝、脾）进行组织学分析，评价CDs的活体毒性。利用1?（3?二甲基氨基丙基）?3?乙基碳化二亚胺盐酸（EDC·HCl）及 N?羟基琥珀酰亚胺（NHS）作为化学耦合剂，将制备的CDs与转铁蛋白（Tf）共价结合成荧光分子探针CDs@Tf。对其表征分析并应用于细胞成像。结果：制得一种平均粒径为3.85 nm的球形荧光CDs，最佳激发波长为400 nm，最大发射波长为520 nm，量子产率高达93%。所制备的CDs具有较高的荧光强度和低细胞毒性等性质。建立的CDs@Tf分子探针能靶向识别H0?8910卵巢癌细胞。结论：成功构建一种光学性能优良、毒性低的靶向性新型荧光纳米探针CDs@Tf，有助于应用于卵巢癌的早期筛查。

Preparation fluorescent carbon dots by solvent - free method and their ovarian cancer cells fluorescence imaging application

Objective CDs@Tf fluorescent nanoprobe based on carbon dots was constructed, the material preparation and their potential application in fluorescence imaging of ovarian cancer cells were discussed. Methods Using sodium citrate dihydrate and urea as raw materials, a high efficiency fluorescent carbon dots (CDs) were prepared by solvent-free method at high temperature. The cell cytotoxicity of CDs was determined by MTS assay against HO-8910 ovarian cancer cells and EA.hy926 umbilical vein endothelial cells. Major organs (heart, lung, kidney, liver, spleen) were collected from kunming mice after 7 days and 21 days of CDs injection via tail vein for histological analysis to evaluate the toxicity of CDs in vivo. Using 1-(3-dimethylaminopropyl) -3-ethylcarbonide diimine hydrochloride (EDC·HCL) and N-hydroxysuccinimide (NHS) as chemical coupling agents, the prepared CDs were covalently combined with transferrin (Tf) to form fluorescent molecular probe CDs@Tf. The probe was characterized and applied to cell imaging. Results The spherical fluorescent CDs with an average diameter of 3.85 nm were prepared,with an optimal excitation wavelength of 400nm and a maximum emission wavelength of 520nm, and quantum yield of 93%. The carbon dots have excellent properties such as high fluorescence intensity and low cytotoxicity. The established CDs@Tf molecular probe can target and identify HO-8910 ovarian cancer cells. Conclusions A novel targeted fluorescent nanoprobe CDs@Tf with excellent optical performance and low toxicity was successfully constructed, which is helpful for the early screening of ovarian cancer.