Abstract
Purpose
To develop optimal microbubble contrast agents (MBCAs) for performing ultrasound microscopy when examining small animals.
Materials and Methods
We prepared three types of MBCAs. First, a mixture of three parts of 40% dextran and one part of 5% human serum albumin were sonicated with perfluorocarbon (PFC) (MB1-D40A5P). Second, three parts of 40% dextran and one part of 1% human serum albumin were sonicated with PFC (MB2-D40A1P). Third, all parts of 1% bovine serum albumin were sonicated with PFC (MB3-A1P). We measured the microbubbles' sizes and concentrations with using image analysis software. The acoustic properties of the microbubbles were assessed both in vitro and in vivo.
Results
The majority of the MB1-D40A5Ps had a diameter of 2-5 um, the mean diameter of the MB2-D40A1Ps was 2.5 um, and the mean diameter of the MB3-A1Ps was less than 2.0 um. Among the microbubbles, the MB1-D40A5Ps and MB2-D40A1Ps showed increased echogenicity in the abdominal vessels, but the duration of their contrast effect was less than 30 sec. On the contrary, the MB3-A1Ps exhibited strong enhancement in the vessels and their duration was greater than 120 sec.