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Reverse-dialysis can be misleading for drug release studies in emulsions as demonstrated by NMR dilution experiments.

ABSTRACT: Emulsions are an important class of carriers for the delivery of hydrophobic drugs. While knowledge of drug release kinetics is critical to optimizing drug carrying emulsions, there remain many open questions about the validity of standard characterization methods such as the commonly used reverse-dialysis. In this paper, the kinetic parameters of isoflurane release in perfluorotributylamine emulsions determined from both reverse-dialysis and nuclear magnetic resonance (NMR) dilution experiments are compared. The NMR-determined kinetic parameters of isoflurane release were found to be approximately seven orders of magnitude larger than those determined from conventional reverse-dialysis and were also shown to be consistent with prior in vivo observations of the anesthetization of rats.

SUBMITTER: Gong Z

PROVIDER: S-EPMC8511114 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Reverse-dialysis can be misleading for drug release studies in emulsions as demonstrated by NMR dilution experiments.

Gong Zhaoyuan Z Tootoonchi Mohammad Hossein MH Fraker Christopher A CA Walls Jamie D JD

International journal of pharmaceutics 20210915

Emulsions are an important class of carriers for the delivery of hydrophobic drugs. While knowledge of drug release kinetics is critical to optimizing drug carrying emulsions, there remain many open questions about the validity of standard characterization methods such as the commonly used reverse-dialysis. In this paper, the kinetic parameters of isoflurane release in perfluorotributylamine emulsions determined from both reverse-dialysis and nuclear magnetic resonance (NMR) dilution experiments ...[more]

PMID: 34534630

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