August 1, 2011.
Nanolipoprotein particles (NLPs) have many potential uses in modern medicine, from cancer therapeutics to vaccine alternatives. As with all pharmaceuticals, the ease of storage and adequate stability of a compound is always a question. It has been found that NLPs can be very stable upon lyophilization, a freeze-drying technique in which all of the water in a sample is removed, if the initial conditions are suitable. In these experiments the stability of NLPs prepared with different combinations of lipids were tested in order to determine the optimum NLP conditions. NLPs composed of different types of lipids were constructed and then lyophilized in a buffered solution containing the sugar trehalose as an excipient. Then the samples were rehydrated and analyzed using size-exclusion chromatography (SEC) to determine if the NLP remained intact. Results indicated that the lipid composition of the NLP plays and important role in the stability upon lyophilization. NLPs prepared with the saturated DMPC lipid are more stable upon lyophilization than those prepared with unsaturated lipids (DOPC and/or DOGS-NTA-Ni), and require less excipient (i.e. trehalose) upon lyophilization to retain structure. These studies will have implications on NLP and storage formulations for vaccine and therapeutic applications.
Lawrence Livermore National Laboratory (LLNL)
This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation.