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

Abstract

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 β-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 (I 616/I 590) 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.

Medical Applications Based on Supramolecular Self-Assembled Materials From Tannic Acid

“…The coordination assembly of TA occurs through the MPN structure to form metal–organic supramolecular assembly materials (Richardson et al, 2016 ). At present, more research is focused on the assembly of TA with iron or ferrous ions, which has many applications in the field of biomedicine such as antibacterial coating (Ko and Huang, 2020 ), clinical diagnosis, nanoprobe treatment (Zou et al, 2018 ; Yan et al, 2019 ), tooth desensitizers (Zhou et al, 2013 ), separation and protection of living cells (Kim et al, 2017 ), self-healing and functional films (Lee et al, 2018 ), and antioxidant coatings (Maerten et al, 2017 ). Ejima et al ( 2013 ) first proposed the synthesis of coordination complexes using natural polyphenol TA as an organic ligand and Fe(III) as an inorganic crosslinking agent, which can be used to prepare various films and particles on a series of substrates by one-step assembly.…”

“…For example, Phiwchai et al ( 2018 ) found that the self-assembled Fe 3+ /TA complex formed by TA binding with extracellular iron has the characteristics of autophagy induction. Yan et al ( 2019 ) designed and assembled an intelligent integrated nanoprobe (THA@Eu-NMOF@Fe/TA) based on the Eu(III) nanometal–organic skeleton (Eu-NMOF), in which photothermal therapy (PTT) and antimicrobial agents are carried out simultaneously by using coordinated complex Fe/TA as a photothermal and antibacterial agent. This opens the way for a new type of cancer treatment probe to achieve real-time temperature sensing feedback in the process of PTT and antibacterial effects, as shown in Figure 7A (Yan et al, 2019 ).…”

“…Yan et al ( 2019 ) designed and assembled an intelligent integrated nanoprobe (THA@Eu-NMOF@Fe/TA) based on the Eu(III) nanometal–organic skeleton (Eu-NMOF), in which photothermal therapy (PTT) and antimicrobial agents are carried out simultaneously by using coordinated complex Fe/TA as a photothermal and antibacterial agent. This opens the way for a new type of cancer treatment probe to achieve real-time temperature sensing feedback in the process of PTT and antibacterial effects, as shown in Figure 7A (Yan et al, 2019 ). In addition, TA can be complexed with other metals such as gold, silver (Fang et al, 2018b ), zirconium (Bag et al, 2015 ), and stainless steel (Xu et al, 2019 ) to obtain supramolecular nanomaterials with different properties and biomedical functions.…”

“… Coordination assembly and application of TA. (A) The application of THA@Eu-NMOF@Fe/TA nanoprobe assembled by coordination (Yan et al, 2019 ). (B) The MPN coatings assembled by crosslinking of metal ions (FeIII, CoII, NiII, CuII, or ZnII) with TA can be used to enhance targeting (Zhang et al, 2020 ).…”

<p>Recent Progress of Nanoscale Metal-Organic Frameworks in Cancer Theranostics and the Challenges of Their Clinical Application</p>

“…Yan et al 64 designed and assembled a smart all-in-one nanoparticle THA@Eu-NMOF@Fe/TA by postsynthetical functionalization of an Eu(III)-based NMOF, which achieved precise temperature sensing and optical heating simultaneously. Fe/TA had PTT effects induced by 808 nm laser irradiation.…”