Design,synthesis,and Biomedical Applications Of BODIPY-based Nanomaterials

Nanomaterials,as an emerging class of materials involving multiple fields and disciplines,?have been rapidly developed and widely used in many fields such as biology,?medicine,and energy in the past years.Boron dipyrromethene(BODIPY)has attracted considerable attention from the researchers for their excellent photophysical and photochemical properties,and outstanding performance as biomedical nanomaterials.In this thesis,we designed and synthesized BODIPY derivatives with different photophysical and photochemical properties by modifying different sites of the BODIPY core.By the nanoprecipitation method,?the BODIPY derivatives could form nanoparticles with different functions.?Subsequently,we investigated the photophysical properties,photochemical properties,and bioapplication of these multifunctional nanoparticles.The specific research contents are as follows.1.We designed and synthesized a pyrazoline-BODIPY(PZL-BDP)with a donor-accepter(D-A)structure.Then,we cultured the single crystal of PZL-BDP and studied its twisted intramolecular charge transfer(TICT)and aggregation-induced emission(AIE)characteristics.?PZL-BDP could assemble into fluorescent nanoparticles(PZL-BDP NPs)which could be an excellent candidate nanomaterial for fluorescence bioimaging duo to their advantages of red emission,large Stokes shift,and desired fluorescence quantum yield.?Moreover,the excellent stability and biocompatibility of PZL-BDP NPs were the prerequisites as a fluorescence bioimaging material for in vitro and in vivo.Especially,?PZL-?BDP NPs could light up the Hela cells in a very short time at room temperature.?PZL-BDP NPs also possessed a perfect in vivo tumor retention capacity,and we could track the fluorescence signal at the tumor site with negligible attenuation for 12 days.2.A facile synthetic diiodo-substituted near-infrared(NIR)BODIPY(SNBDP)with good photophysical properties has been successfully established by Knoevenagel condensation reaction.The SNBDP nanoparticles(SNBDP NPs)were prepared by the nanoprecipitation method wrapped by poloxamer(F127)for photodynamic therapy(PDT).SNBDP NPs exhibited excellent singlet oxygen generation ability,and favorable stability both in aqueous media and upon irradiation.Furthermore,SNBDP NPs could be effectively internalized by cancer cells and kill the cells in the presence of irradiation.3.We designed and synthesized two NIR BODIPY dyes(BDC and BSC),which employed coumarin and BODIPY as raw materials by the improved Knoevenagel condensation reaction.?BDC and BSC possessed different conjugate degrees,which made their photophysical properties poles apart.After the self-assembling of BDC and BSC,the newly constructed nanoparticles(BDC NPs and BSC NPs)demonstrated good biocompatibility.Moreover,BDC NPs exhibited a good photothermal effect upon the irradiation of an 808 nm laser,which could effectively inhibit the growth of HeLa cells,and BSC NPs could quickly show a conspicuous fluorescence in the HeLa cells.4.We developed a donor-acceptor-donor(D-A-D)BODIPY(NBB)which possessed strong absorption at the NIR region(808 nm)due to the multi-intersection of intramolecular charge transfer(ICT),photoinduced electron transfer(PET),and heavy atom effects.By the nanoprecipitation method,the NBB nanoparticles(NBB NPs)were facilely prepared,which could exhibit favorable water-stability and photostability.In particular,the outstanding photon absorption capacity endows NBB NPs with high photothermal conversion efficiency(? = 53.8%),and active singlet oxygen generation ability upon 808 nm laser irradiation,which promotes their tumor inhibition efficiency via the combination of photothermal/photodynamic therapy.