To prepare RGD peptide modified perfluorohexane ( PFH ) polymer nanoparticles RGD‐PFH‐NPs and investigate its basic characteristics ,targeting ability and combine with low‐intensity focused ultrasound ( LIFU ) for ultrasonic imaging in vivo and vitro . Methods Targeted nanoparticles RGD‐PFH‐NPs were prepared by double emulsifying method and carbodiimide method . T heir morphology and distribution were observed . T he particle size ,zeta potential and connection probability were measured . T he phase‐changed properties and the LIFU‐induced imaging ability in contrast‐enhanced ultrasound mode of RGD‐PFH‐NPs were investigated in vivo and vitro . T he tagetability of nanoparticles to human gastric cancer cell line M GC803 and tumor‐bearing nude mouse were observed through targeting group and non‐targeting group . Results T he prepared sample was milky w hite suspension liquid . T he RGD‐PFH‐NPs were spherical uniform size ,good dispersion w hen observed through the optical microscope and transmission electron microscopy . T he particle size was ( 259 .3 ± 42 .6) nm and the Zeta potential was ( －17 .6+5 .4) mV . T he connection probability of RGD peptide was 89 .13% . With 70℃ water bath and LIFU stimulation RGD‐PFH‐NPs can remarkably change phase and show good imaging performance in both conventional ultrasound and contrast‐enhanced ultrasound mode in vivo and vitro . The connection probability to M GC803 cells in targeting group ( RGD‐PFH‐NPs ) and the non‐targeting group( PFH‐NPs) were 82 .59% and 2 .96% . T he accumulation of nanoparticles in the RGD‐PFH‐NPs group in tumor tissues was significantly higher than that in the non‐targeted PFH‐NPs group( P) . Conclusions The constructed nanoparticles RGD‐PFH‐NPs ,providing contrast‐enhanced ultrasonic imaging and excellent targeting ability to human gastric cancer cells M GC803 and gastric cancer tissue ,is expected to become a new type of gastric cancer targeted ultrasound contrast agent .

Objective To prepare RGD peptide modified perfluorohexane ( PFH ) polymer nanoparticles RGD-PFH-NPs and investigate its basic characteristics ,targeting ability and combine with low-intensity focused ultrasound ( LIFU ) for ultrasonic imaging in vivo and vitro . Methods Targeted nanoparticles RGD-PFH-NPs were prepared by double emulsifying method and carbodiimide method . Their morphology and distribution were observed . The particle size ,zeta potential and connection probability were measured . The phase-changed properties and the LIFU-induced imaging ability in contrast-enhanced ultrasound mode of RGD-PFH-NPs were investigated in vivo and vitro . The tagetability of nanoparticles to human gastric cancer cell line MGC803 and tumor-bearing nude mouse were observed through targeting group and non-targeting group . Results The prepared sample was milky white suspension liquid . The RGD-PFH-NPs were spherical uniform size ,good dispersion when observed through the optical microscope and transmission electron microscopy . The particle size was ( 259 .3 ± 42 .6) nm and the Zeta potential was ( -17 .6+5 .4) mV . The connection probability of RGD peptide was 89 .13％ . With 70℃ water bath and LIFU stimulation RGD-PFH-NPs can remarkably change phase and show good imaging performance in both conventional ultrasound and contrast-enhanced ultrasound mode in vivo and vitro . The connection probability to MGC803 cells in targeting group ( RGD-PFH-NPs ) and the non-targeting group( PFH-NPs)were 82 .59％ and 2 .96％ . The accumulation of nanoparticles in the RGD-PFH-NPs group in tumor tissues was significantly higher than that in the non-targeted PFH-NPs group( P) . Conclusions The constructed nanoparticles RGD-PFH-NPs ,providing contrast-enhanced ultrasonic imaging and excellent targeting ability to human gastric cancer cells MGC803 and gastric cancer tissue ,is expected to become a new type of gastric cancer targeted ultrasound contrast agent .