Department of Chemistry of College of Staten Island and The Graduate Center, The City University of New York, Staten Island, NY 10314, USA.
Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
Biomaterials. 2015 Jun;53:117-26. doi: 10.1016/j.biomaterials.2015.02.087. Epub 2015 Mar 12.
An efficient nanomedical platform that can combine two-photon cell imaging, near infrared (NIR) light and pH dual responsive drug delivery, and photothermal treatment was successfully developed based on fluorescent porous carbon-nanocapsules (FPC-NCs, size ∼100 nm) with carbon dots (CDs) embedded in the shell. The stable, excitation wavelength (λex)-tunable and upconverted fluorescence from the CDs embedded in the porous carbon shell enable the FPC-NCs to serve as an excellent confocal and two-photon imaging contrast agent under the excitation of laser with a broad range of wavelength from ultraviolet (UV) light (405 nm) to NIR light (900 nm). The FPC-NCs demonstrate a very high loading capacity (1335 mg g(-1)) toward doxorubicin drug benefited from the hollow cavity structure, porous carbon shell, as well as the supramolecular π stacking and electrostatic interactions between the doxorubicin molecules and carbon shell. In addition, a responsive release of doxorubicin from the FPC-NCs can be activated by lowering the pH to acidic (from 7.4 to 5.0) due to the presence of pH-sensitive carboxyl groups on the FPC-NCs and amino groups on doxorubicin molecules. Furthermore, the FPC-NCs can absorb and effectively convert the NIR light to heat, thus, manifest the ability of NIR-responsive drug release and combined photothermal/chemo-therapy for high therapeutic efficacy.
一种高效的纳米医学平台，它可以结合双光子细胞成像、近红外（NIR）光和 pH 双响应药物传递以及光热治疗，是基于荧光多孔碳纳米胶囊（FPC-NC，尺寸约为 100nm）成功开发的，其中嵌入了碳点（CDs）。多孔碳壳中嵌入的 CDs 具有稳定的、可激发波长（λ ex）可调谐的上转换荧光，使 FPC-NC 能够在从紫外光（405nm）到近红外光（900nm）的宽波长激光激发下，作为一种优异的共聚焦和双光子成像对比剂。FPC-NC 对阿霉素药物具有非常高的负载能力（1335mg g-1），这得益于空心腔结构、多孔碳壳以及阿霉素分子和碳壳之间的超分子π堆积和静电相互作用。此外，由于 FPC-NC 上存在 pH 敏感的羧基和阿霉素分子上的氨基，FPC-NC 可以通过降低 pH 值至酸性（从 7.4 降低至 5.0）来激活阿霉素的响应性释放。此外，FPC-NC 可以吸收并有效将 NIR 光转化为热量，从而表现出 NIR 响应性药物释放和联合光热/化疗的能力，以实现高治疗效果。
