药物快速代谢及无法高浓度聚集肿瘤组织是长期以来胰腺癌化疗耐受的关键原因；现有的各种影像学手段又无法及时评价治疗疗效。课题组前期利用PLGA/PEG材料制备荷药载体，提高了易降解药物的生物利用率并能促进药物在体内长效循环；利用超声靶向破坏微泡（UTMD）技术增强了载药纳米粒在局部组织的摄取。但靶向性调控药物释放和浓集及瞬时"可视化"特异成像评价胰腺癌治疗疗效是亟需解决的两大技术难题。本课题拟制备PLGA/PEG新型金纳米微囊，将其内部包裹易降解的吉西他滨(dFdC)，表面修饰特异识别胰腺癌细胞的CA19-9及CEA抗体；在UTMD"助推"下荷药载体特异性大量进入胰腺癌细胞；同时利用载体表面纳米金颗粒的表面效应和声学散射特性进行分子靶向超声造影成像，以期实现提高胰腺癌化疗疗效的同时，及时进行分子靶向超声造影成像评估胰腺癌的治疗疗效，从而为胰腺癌建立一项安全有效的一体化分子靶向辅助治疗新手段。

It has been reported that the crucial reason of insensitiveness of pancreatic cancer to chemotherapy is the rapid inactivation of the chemotherapy drug and the very low amount of drug deposition in tumor. Moreover, recent radiology technology cannot evaluate chemotherapy effect in time. In our previous study, it has been found that nano particles prepared by PLGA/PEG material can increase the bioactivity of easily degraded chemotherapy drug and improve its long term systemic circulation, in addition, Ultrasound Targeted Microbubble Destruction (UTMD) technology could enhance the delivery of nano particles. However, resolving the the difficulties of modulating target drug depositon and innovating corresponding imaging technology to instantaneously visualize the therapy effect are in urgent need. This study will be carried on first by preparing the PLGA/PEG-Gold nano capsule, in which wrapped with easily degraded gemcitabine, and on surface of which modified with specific antibody CA19-9 and CEA. Secondly, This multifunctional carrier will consquently be propelled by UTMD in order to increase the drug intake. Meanwhile, the acoustic scattering characteristic of gold nano particles on carrier surface will be used to real time imaging under ultrasound. The purpose of this study is to establish a new mode of adjuvant therapy in pancreatic cancer, which integrates not only effective and safe cell targeted chemotherapy but a new real time cell target imaging method.