Design and spectroscopic characterization of novel series of near infrared indocyanine dyes

Design, synthesis and application of near-infrared fluorescence probe IR-780-Crizotinib in detection of ALK positive tumors

At present, the early diagnosis and treatment of NSCLC has become an international research hotspot. However, how to realize the organic combination of highly sensitive and high-resolution tumor imaging diagnosis and effective treatment, and to provide effective information for the diagnosis and treatment of cancer is still a major problem in the integration of cancer diagnosis and treatment. In this study, based on the Crizotinib has a good targeted inhibitory effect on ALK positive tumor cells, the near-infrared targeted fluorescent dye IR-780 was covalently bound with the drug molecule Crizotinib, thus the near-infrared fluorescent probe IR-780-Crizotinib targeting ALK positive tumor cells was synthesized. The probe structure is confirmed by NMR and MS. The optical properties of the fluorescent probe and the imaging process in ALK positive tumor-bearing mice were analyzed using ultraviolet spectrophotometer, near-infrared fluorescence spectrometer, and near-infrared fluorescence imaging system. The results show that the probe had better photoactivity. In vivo imaging shows that the probe maintained the biological activity of Crizotinib, effectively targeting the tumor site involved with clear imaging, and ultimately excreted from the body. It was confirmed that the probe could be used for the tracking, positioning and targeted therapy of nude mice with ALK positive tumors in vivo, thus exploring a new approach for the clinical application of near-infrared fluorescent probe to detect ALK positive tumors in the future.

Electron Donor-Acceptor Effect-Induced Organic/Inorganic Nanohybrids with Low Energy Gap for Highly Efficient Photothermal Therapy

For the design and optimization of near-infrared photothermal nanohybrids, tailoring the energy gap of nanohybrids plays a crucial role in attaining a satisfactory photothermal therapeutic efficacy for cancer and remains a challenge. Herein, we report an electron donor-acceptor effect-induced organic/inorganic nanohybrid with a low energy gap (denoted as ICG/Ag/LDH) by the in situ deposition of Ag nanoparticles onto the CoAl-LDH surface, followed by the coupling of ICG. A combination study verifies that the supported Ag nanoparticles as the electron donor (D) push electrons into the conjugated system of ICG by the electronic interaction between ICG and Ag, while OH groups of LDHs as the electron acceptor (A) pull electrons from the conjugated system of ICG by hydrogen bonding (N···H-O). This induces the formation of the D-A conjugated π-system and has a strong influence on the π-conjugated system of ICG, thus leading to a prominent decrease toward the energy gap and correspondingly an ultra-long redshift (∼115 nm). The resulting ICG/Ag/LDHs show an enhanced photothermal conversion efficiency (∼45.5%) at 808 nm laser exposure, which is ∼1.6 times larger than that of ICG (∼28.4%). Such a high photothermal performance is attributed to the fact that ICG/Ag/LDHs possess a D-π-A hybrid structure and a resulting lower energy gap, thus effectively promoting nonradiative transitions and leading to enhancement of the photothermal effect. Both in vitro and in vivo results confirm the good biocompatible properties and capability of the ICG/Ag/LDHs for NIR-triggered cancer treatment. This research demonstrates a successful paradigm for the rational design and preparation of new nanohybrids through the modulation of electron donor-acceptor effect, which offers a new avenue to achieve efficient phototherapeutic agent for improving the cancer therapeutic outcomes.