Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Nagoya, Japan.
PLoS One. 2012;7(6):e39057. doi: 10.1371/journal.pone.0039057. Epub 2012 Jun 18.
Multifunctional envelope-type nanodevices (MENDs) are very promising non-viral gene delivery vectors because they are biocompatible and enable programmed packaging of various functional elements into an individual nanostructured liposome. Conventionally MENDs have been fabricated by complicated, labor-intensive, time-consuming bulk batch methods. To avoid these problems in MEND fabrication, we adopted a microfluidic chip with a chaotic mixer array on the floor of its reaction channel. The array was composed of 69 cycles of the staggered chaotic mixer with bas-relief structures. Although the reaction channel had very large Péclet numbers (>10(5)) favorable for laminar flows, its chaotic mixer array led to very small mixing lengths (<1.5 cm) and that allowed homogeneous mixing of MEND precursors in a short time. Using the microfluidic chip, we fabricated a double-lamellar MEND (D-MEND) composed of a condensed plasmid DNA core and a lipid bilayer membrane envelope as well as the D-MEND modified with trans-membrane peptide octaarginine. Our lab-on-a-chip approach was much simpler, faster, and more convenient for fabricating the MENDs, as compared with the conventional bulk batch approaches. Further, the physical properties of the on-chip-fabricated MENDs were comparable to or better than those of the bulk batch-fabricated MENDs. Our fabrication strategy using microfluidic chips with short mixing length reaction channels may provide practical ways for constructing more elegant liposome-based non-viral vectors that can effectively penetrate all membranes in cells and lead to high gene transfection efficiency.
多功能信封型纳米器件 (MENDs) 是非常有前途的非病毒基因传递载体，因为它们具有生物相容性，并能够将各种功能元件编程包装到单个纳米结构脂质体中。传统上，MENDs 是通过复杂的、劳动密集型的、耗时的批量方法制造的。为了避免在 MEND 制造中出现这些问题，我们采用了一种带有混沌混合器阵列的微流控芯片，该芯片位于其反应通道的底部。该阵列由 69 个交错的混沌混合器组成，带有浮雕结构。尽管反应通道的 Peclet 数非常大（>10(5)），有利于层流，但它的混沌混合器阵列导致混合长度非常小（<1.5 厘米），从而允许在短时间内均匀混合 MEND 前体。使用微流控芯片，我们制造了一种由浓缩质粒 DNA 核和脂质双层膜信封组成的双层 MEND (D-MEND)，以及用跨膜肽八精氨酸修饰的 D-MEND。与传统的批量方法相比，我们的芯片上实验室方法制造 MENDs 更加简单、快速和方便。此外，与批量制造的 MEND 相比，芯片上制造的 MEND 的物理性质相当或更好。我们使用具有短混合长度反应通道的微流控芯片的制造策略可能为构建更优雅的基于脂质体的非病毒载体提供实用方法，这些载体可以有效地穿透细胞中的所有膜，并导致高基因转染效率。
