Transarterial Infusion Of Polyaniline Nanorods For In Situ NIR-Ⅱ Photothermal Therapy Of VX2 Tumor In Rabbit Liver

Purpose:The second generation of near-infrared photothermal therapy(NIR-ⅡPTT)has become a promising tumor treatment strategy because of its safety and efficacy.In recent years,a variety of near-infrared absorption nanomaterials have been used in near-infrared photothermal therapy for tumors.Polyaniline has attracted great attention because of its strong near-infrared absorption ability,good photothermal conversion performance,excellent photostability,good biocompatibility and easy chemical diffusion.However,due to the low dose of NIR-Ⅱ nanomaterials and the lack of laser energy to irradiate deep tumors,the application of NIR-Ⅱ PTT in the treatment of deep solid tumors is limited.The purpose of this study is to introduce the concept of minimally invasive interventional therapy,improve the traditional ablation mode,and realize the effective aggregation of nanomaterials in tumors and the efficient treatment of deep solid tumors with NIR-Ⅱ PTT.Methods:Polyaniline nanoparticles(HPW@PANI)were prepared by chemical oxidative polymerization using phosphotungstic acid as catalyst.Set up the in vitro control test,(1)control group,(2)1064 nm near infrared light,(3)HPW@PANI nanorods,(4)HPW@PANI nanorods+1064 nm near infrared light(NIR-Ⅱ PTT group),to test the photothermal conversion properties,photostability and biocompatibility of HPW@PANI nanorods.In this experiment,the in situ NIR-Ⅱ PTT therapy based on laser power transmitted by optical fiber and HPW@PANI nanoparticles absorbed by transarterial infusion for NIR-Ⅱ was applied to the treatment of VX2 tumor in Rabbit Liver.Results:The extinction coefficient of HPW@PANI nanoparticles at the near infrared light of 1064nm is 12.53L/g.cm,and the photothermal conversion efficiency is 57.76%.It can achieve the purpose of high temperature ablation of cancer cells in a short time,and has good photostability and biosafety.In vivo experiment(1)HPW@PANI+NIR-Ⅱ PTT(2)PBS+NIR-Ⅱ PTT.In the experimental group,the temperature of the tumor in situ rose rapidly to 60℃ within 3 minutes,and the temperature of the surrounding normal liver parenchyma remained below 38℃.The HE staining of orthotopic tumor showed that a large number of cells were necrotic.The expression of Ki67 was decreased significantly and the expression of N-cadherin and Vimentin in the distal tumor was significantly down-regulated.While the control group had more ascites and a large number of peritoneal metastasis visibly.In a word,the rapid aggregation of HPW@PANI nanoparticles in tumor can be achieved by hepatic artery perfusion,and the laser energy of 1064nm transmitted by optical fiber for in situ NIR-ⅡPTT can ablate the tumor in situ,inhibit distant tumor growth and inhibit peritoneal metastasis.Conclusion:In this experiment,we propose to use the principle of the Transcatheter Arterial chemoembolization(TACE)for Classical liver Cancer surgery to inject NIR-Ⅱ absorbable nanoparticles into tumor tissue,and combined with percutaneous liver puncture to establish a channel to introduce optical fiber transmission energy to solve the problem of the lack of near-infrared light penetration depth.This study provides a new direction for the application of in situ NIR-Ⅱ PTT based on optical fiber transmission of laser power and transarterial infusion of NIR-Ⅱnanomaterials in the treatment of deep tumors.