Preparation and characterization of microbubbles loaded with hydrogen sulfide / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To prepare a phospholipid-coated microbubble loaded with hydrogen sulfide (HSMB) and evaluate its physicochemical and acoustic properties.</p><p><b>METHODS</b>Hydrogen sulfide and perfluoropropane were mixed at the ratios of 40, 31, 22, 13, and 04 to prepare hydrogen sulfide-loaded microbubbles (termed HSMB40, HSMB31, HSMB22, HSMB13, and HSMB04, respectively). The microbubble concentration and diameter were investigated and their stability were evaluated. The optimal ratio of hydrogen sulfide and perfluoropropane was determined according to the changes of microbubble concentration. The changes of dissolved hydrogen sulfide and concentration of the microbubbles were investigated after exposure to ultrasound, and their acoustic enhancement effects in the myocardium and kidney were observed after intravenous injection in rats.</p><p><b>RESULTS</b>HSMBs were milky in color and spherical in shape without aggregations. The concentrations of HSMB40 and HSMB31 were lower than that of HSMB22 and decreased with time. HSMB22, HSMB13 and HSMB04 showed comparable concentrations and were stable within 72 h. After exposure to ultrasound, the concentration of HSMB22 decreased while the dissolved hydrogen sulfide increased significantly. Intravenous injection of HSMB22 produced a satisfactory contrast-enhancing effect in the myocardium and kidney of rats.</p><p><b>CONCLUSION</b>HSMB prepared with the hydrogen sulfide to perfluoropropane ratio of 22 has excellent contrast-enhancing effect and is capable of carrying and releasing hydrogen sulfide upon ultrasound exposure to potentially allow visual site-specific delivery of hydrogen sulfide.</p>