Demonstration of π-π Stacking at Interfaces: Synthesis of an Indole-Modified Monodisperse Silica Microsphere SiO2@IN.

In the present study, a novel silane coupling agent, designated INSi, was synthesized via a facile synthetic route, incorporating indole-functional moieties. This agent was further employed for the surface modification of homemade silica nanomicrospheres (SMPs). The ensuing nanomicrosphere composite, denoted as SiO2@IN, exemplified pronounced interfacial π-π interactions. Optimization of the reaction conditions was conducted using the response surface optimization technique. Subsequent validation of interfacial π-π interactions was accomplished through a synergistic approach, integrating theoretical calculations and comprehensive analyses of spectral and morphological attributes exhibited by the SiO2@IN.

Smart All-in-One Thermometer-Heater Nanoprobe Based on Postsynthetical Functionalization of a Eu(III)-Metal-Organic Framework.

Real-time temperature feedback in tissue based on photothermal therapy is an urgent problem to be solved in cancer treatment. Herein, a smart all-in-one nanoprobe THA@Eu-NMOF@Fe/TA was designed and assembled by postsynthetical functionalization of an Eu(III)-based nanoscale metal-organic framework (Eu-NMOF) with a two-photon-absorbing ß-diketonate ligand 4,4,4-trifluoro-1-(9-hexylcarbazol-3-yl)-1,3-butanedione (HTHA) and Fe(III)/tannic acid assembly (Fe/TA). Such a functionalized material can simultaneously achieve the temperature-sensing and optical heating under a single beam of near-infrared (NIR) light. Under 808 nm laser excitation, real-time feedback of temperature by monitoring thermoresponsive fluorescence emission ratio ( I616/ I590) and fluorescence lifetime of Eu(III) ions were realized. Meantime, Fe/TA served as the photothermal agent and antibacterial agent to implement photothermal therapy (PTT) and antibacteria simultaneously. The functions of the nanoprobe were proved with ex vivo experiments, and the antibacterial activity against Gram-positive and Gram-negative bacteria of the probe was also elaborately evaluated. Our work paves a new avenue for engineering a new cancer treatment probe which can achieve real-time temperature sensing feedback during PTT and antibacterial process.

Functionalized Eu(III)-Based Nanoscale Metal-Organic Framework To Achieve Near-IR-Triggered and -Targeted Two-Photon Absorption Photodynamic Therapy.

The postsynthetic-modified nanoscale metal-organic framework (NMOF) probes selected as potential drug delivery platforms and photodynamic therapy agents to fulfill the effective and safe treatment of neoplastic diseases have attracted increasing attention recently. Herein, a Eu(III)-based NMOF probe elaborately postsynthetically modified with a ß-diketonate two-photon-absorbing (TPA) ligand is rationally designed and further functionalized by assembling the photosensitizer molecule (methylene blue, MB) in the pores and a cyclic peptide targeting motif on the surface of the NMOF, which could achieve highly efficient near-infrared (NIR)-triggered and -targeted photodynamic therapy (PDT). On the basis of the luminescence resonance energy transfer process between the NMOF donor and the photosensitizer MB acceptor, the probe can achieve a high tissue-penetrable TPA-PDT effect. Thus, the NMOFs in this study play the role of not only the nanocontainer for the photosensitizer but also the energy-transfer donor. Studies in vitro show enhanced cellular uptake and satisfactory PDT effectiveness toward cancer cells compared to the free photosensitizer MB. It is highly expected that this study contributes to the development of smart luminescent diagnostic and therapeutic probes.