This work was to compare the encapsulation efficiency and ultrasound-triggered release for protein between microbubbles and liposomes. Bovine serum albumin (BSA) was used as a model. Final ratios between BSA and HPC in microbubbles and liposomes were 1:5, 1:7 and 1:10, respectively. Morphologic characteristics and contrast enhancement of loaded microbubbles and liposomes were measured. Encapsulation efficiency and ultrasound-stimulated release profile were detected. The mean size of loaded microbubbles and liposomes was 3.4 microm and 1.7 microm, respectively. Encapsulation efficiency of microbubbles had an inverse relationship with the ratio between BSA and HPC, while loaded liposomes remained nearly unchanged in the designed range of the ratio between BSA and HPC. Microbubbles resulted in significant enhancement of CnTi images. After ultrasound, more than 90% of the entrapped BSA was released from microbubbles, but less than 5% of BSA released from liposomes. Microbubbles are a promising delivery system for proteins.

Protein-loaded PUM exhibited satisfactory physical characteristics and were potent for using in ultrasound-triggered delivery.

ABSTRACT. The aim of this study was to investigate the effect of the CYP2C9*3 (CYP2C9 1075 A>C) polymorphism on meloxicam pharmacokinetics in a Chinese population. Twenty-four healthy volunteers were enrolled in this study. The pyrosequencing technique was used to identify polymorphisms of CYP2C9. The concentration of meloxicam in plasma was determined by a high-performance liquid chromatography assay with mass spectrographic analysis. The Drug and Statistics Software (DAS, version 2.0) was used for curve fitting and calculations of pharmacokinetic parameters. The effects of CYP2C9*3 variant genotypes on meloxicam pharmacokinetics were compared with those of the wild type genotype. Among the 24 volunteers, two AC heterozygotes were observed in the multi-dose group. CYP2C9*3 was found to play an important role in the metabolism of meloxicam by reducing its enzymatic activity. Therefore, results of this study provide helpful information regarding inter-individual pharmacokinetic variability in the Chinese population.

No abstract

This work was to compare the encapsulation efficiency and ultrasound-triggered release for protein between microbubbles and liposomes. Bovine serum albumin (BSA) was used as a model. Final ratios between BSA and HPC in microbubbles and liposomes were 1:5, 1:7 and 1:10, respectively. Morphologic characteristics and contrast enhancement of loaded microbubbles and liposomes were measured. Encapsulation efficiency and ultrasound-stimulated release profile were detected. The mean size of loaded microbubbles and liposomes was 3.4 microm and 1.7 microm, respectively. Encapsulation efficiency of microbubbles had an inverse relationship with the ratio between BSA and HPC, while loaded liposomes remained nearly unchanged in the designed range of the ratio between BSA and HPC. Microbubbles resulted in significant enhancement of CnTi images. After ultrasound, more than 90% of the entrapped BSA was released from microbubbles, but less than 5% of BSA released from liposomes. Microbubbles are a promising delivery system for proteins.