Value of Flexible Nano-Sensor with Carbon Nanotube and Graphene in Ultrasound Screening of Congenital Heart Malformations in Early Pregnancy

Abstract

This study aimed to explore the application value of flexible nano-sensors with carbon nanotube (CNT) and graphene (Gr) in the ultrasound screening of congenital heart defects (CHD) in early pregnancy. The change of the sensitivity strain factor, mechanical properties, and resistance changes of the flexible nanosensor were analysed under different strains. The prenatal ultrasound diagnosis of early pregnancy 2640 pregnant women was selected as the research object. The nuchal translucency (NT) thickening value, blood flow spectrum of ductus venosus (DV), ductus venosus a (DVa) wave, and tricuspid regurgitation (TR) were measured under the ultrasound diagnosis. In addition, the sensitivity and specificity of different indicators in screening the cardiac malformations were compared. It was found that when the volume ratio of CNT:Gr was 1:5, the initial resistance of the sensor was the smallest; the resistance of the sensor was 2.75 KΩ˜4.68 KΩ when the strain was 1%; and the maximum frequency of the sensor was 0.25. NT+TR+DVa wave (DVa) combined diagnosis detected 8 cases of CHD, the sensitivity and specificity were 80% and 96.48%, respectively. The sensitivity of combined diagnosis of NT+TR+DVa was greatly higher than that of NT, DV and TR alone. It indicated that the flexible nano sensor based on CNT and Gr in this study showed good stability and durability, and high sensitivity in the diagnosis of fetal structure and cardiac malformations, which can provide reference value for the screening of fetal diseases in early pregnancy.