Spray-Dried Multiscale Nano-biocomposites Containing Living Cells

详细信息    查看全文

• 作者：Patrick E. Johnson ; Pavan Muttil ; Debra MacKenzie ; Eric C. Carnes ; Jennifer Pelowitz ; Nathan A. Mara ; William M. Mook ; Stephen D. Jett ; Darren R. Dunphy ; Graham S. Timmins ; C. Jeffrey Brinker
• 刊名：ACS Nano
• 出版年：2015
• 出版时间：July 28, 2015
• 年：2015
• 卷：9
• 期：7
• 页码：6961-6977
• 全文大小：908K
• ISSN：1936-086X

文摘

Three-dimensional encapsulation of cells within nanostructured silica gels or matrices enables applications as diverse as biosensors, microbial fuel cells, artificial organs, and vaccines; it also allows the study of individual cell behaviors. Recent progress has improved the performance and flexibility of cellular encapsulation, yet there remains a need for robust scalable processes. Here, we report a spray-drying process enabling the large-scale production of functional nano-biocomposites (NBCs) containing living cells within ordered 3D lipid鈥搒ilica nanostructures. The spray-drying process is demonstrated to work with multiple cell types and results in dry powders exhibiting a unique combination of properties including highly ordered 3D nanostructure, extended lipid fluidity, tunable macromorphologies and aerodynamic diameters, and unexpectedly high physical strength. Nanoindentation of the encasing nanostructure revealed a Young鈥檚 modulus and hardness of 13 and 1.4 GPa, respectively. We hypothesized this high strength would prevent cell growth and force bacteria into viable but not culturable (VBNC) states. In concordance with the VBNC state, cellular ATP levels remained elevated even over eight months. However, their ability to undergo resuscitation and enter growth phase greatly decreased with time in the VBNC state. A quantitative method of determining resuscitation frequencies was developed and showed that, after 36 weeks in a NBC-induced VBNC, less than 1 in 10鈥?00 cells underwent resuscitation. The NBC platform production of large quantities of VBNC cells is of interest for research in bacterial persistence and screening of drugs targeting such cells. NBCs may also enable long-term preservation of living cells for applications in cell-based sensing and the packaging and delivery of live-cell vaccines.