In recent years,in order to reduce the side effects and improve the treatment efficiency,people are eager to seek a variety of methods to treat cancer.It is very important to develop a nanodrug delivery system that can simultaneously monitor its efficacy in order to avoid damage to normal tissues as much as possible.With the development of nanotechnology,great progress has been made in nano drug delivery system.Nano drug delivery system requires that it can maintain a stable structure before reaching the tumor site,and release drugs effectively under certain stimulus response(light,ultrasound,p H,temperature,redox,enzyme,etc.).Among all kinds of stimulus responses,light stimulation has attracted more and more attention due to its excellent characteristics such as high spatial-temporal resolution,remote operation,non-invasive and so on.In recent years,near infrared two zone(nir-ii,1000-1700nm)fluorescence imaging technology has been widely concerned by the majority of researchers.Due to the long emission wavelength of this band and the weak light scattering and spontaneous fluorescence of biological tissues,nir-ii fluorescence imaging technology has effectively improved the penetration depth and imaging quality,These advantages make it have very important application value in biomedical imaging and life science.Based on this,two different ideas are put forward in this paper:(1)Near infrared two zone fluorescence imaging guided photothermal / photodynamic therapy:through near infrared two zone fluorescence imaging,guided single laser trigger material photothermal / photodynamic therapy.In this paper,we have successfully designed and constructed a multi-functional nano particle Dtp T NPs based on single component asymmetric small organic molecules.The Dtp T NPs developed in this paper have strong absorption capacity at 808 nm,excellent near-infrared region II(nir-ii)fluorescence emission performance,and significant ability to produce singlet oxygen and high temperature(photothermal conversion efficiency up to 61.6%).In addition,under a single 808 nm laser irradiation,the tumor inhibition rate of multi-functional nanoparticles Dtp T NPs was proved to be 90.8%,which was due to its satisfactory nir-ii fluorescence imaging and photothermal / photodynamic properties.At the same time,multi-functional nanoparticles Dtp T NPs show excellent biocompatibility with normal tissues,which further proves the potential application of multi-functional nanoparticles Dtp T NPs in clinical practice.This work provides a new idea for the construction of high-performance photothermal nano platform for small organic molecules.(2)Photothermal therapy guided by near infrared two zone fluorescence imaging: guided by near infrared two zone fluorescence imaging,1064 nm laser triggered photothermal therapy of monothiophene polymer.In short,in this project,we successfully designed a single thiophene polymer based nanoparticles with high photothermal properties and photostability.The nanoparticles have strong absorption and emission in the nir-ii region,and have good photothermal conversion efficiency(40.8%)when irradiated by a single light source 1064 nm laser.In addition,it has excellent photostability.The absorbance of the nanoparticles hardly changes after 30 minutes irradiation with808 nm laser.In addition to the above studies,we also studied the biocompatibility and photothermal therapeutic effect of the nanoparticles in cells.After co cultured with NIH-3T3 normal cells,the cells did not show obvious apoptosis,which proved that the nanoparticles had good biocompatibility.After co cultured with He La cells and irradiated with 1064 nm laser,the cells showed regular apoptosis with the increase of the concentration of nanoparticles,which indicated that the nanoparticles had good photothermal therapeutic effect.These studies provide a basis for its application in tumor targeted photothermal therapy guided by near infrared two zone fluorescence imaging,and have a good clinical application prospect. |