Ja'afar Fairuzeta, Leow Chee Hau, Garbin Valeria, Sennoga Charles A, Tang Meng-Xing, Seddon John M
Department of Chemistry, Imperial College London, London, UK.
Department of Bioengineering, Imperial College London, London, UK.
Ultrasound Med Biol. 2015 Nov;41(11):2990-3000. doi: 10.1016/j.ultrasmedbio.2015.07.001. Epub 2015 Aug 28.
Microbubble (MB) contrast-enhanced ultrasonography is a promising tool for targeted molecular imaging. It is important to determine the MB surface charge accurately as it affects the MB interactions with cell membranes. In this article, we report the surface charge measurement of SonoVue, Definity and Optison. We compare the performance of the widely used laser Doppler electrophoresis with an in-house micro-electrophoresis system. By optically tracking MB electrophoretic velocity in a microchannel, we determined the zeta potentials of MB samples. Using micro-electrophoresis, we obtained zeta potential values for SonoVue, Definity and Optison of -28.3, -4.2 and -9.5 mV, with relative standard deviations of 5%, 48% and 8%, respectively. In comparison, laser Doppler electrophoresis gave -8.7, +0.7 and +15.8 mV with relative standard deviations of 330%, 29,000% and 130%, respectively. We found that the reliability of laser Doppler electrophoresis is compromised by MB buoyancy. Micro-electrophoresis determined zeta potential values with a 10-fold improvement in relative standard deviation.
微泡（MB）增强超声检查是一种很有前景的靶向分子成像工具。准确测定MB表面电荷很重要，因为它会影响MB与细胞膜的相互作用。在本文中，我们报告了声诺维、德芬蒂尼和欧普帝声的表面电荷测量结果。我们将广泛使用的激光多普勒电泳与内部微电泳系统的性能进行了比较。通过光学跟踪微通道中MB的电泳速度，我们测定了MB样品的zeta电位。使用微电泳，我们得到声诺维、德芬蒂尼和欧普帝声的zeta电位值分别为-28.3、-4.2和-9.5 mV，相对标准偏差分别为5%、48%和8%。相比之下，激光多普勒电泳得到的值分别为-8.7、+0.7和+15.8 mV，相对标准偏差分别为330%、29000%和130%。我们发现激光多普勒电泳的可靠性受到MB浮力的影响。微电泳测定的zeta电位值相对标准偏差提高了10倍。
