[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

基礎講座 電気泳動(Electrophoresis)

Micro total analysis systems. Latest advancements and trends.

Enzymes inside lipid vesicles: preparation, reactivity and applications.

http://research.vuse.vanderbilt.edu/srdesign/2006/group19/Microfluidicstechnologyformanipulationandanalysisofbiologicalcells.pdf

Microfluidics technology for manipulation and analysis of biological cells

Micelle-mediated extraction

Food and water contamination cause safety and health concerns to both animals and humans. Conventional methods for monitoring food and water contamination are often laborious and require highly skilled technicians to perform the measurements, making the quest for developing simpler and cost-effective techniques for rapid monitoring incessant. Since the pioneering works of Whitesides’ group from 2007, interest has been strong in the development and application of microfluidic paper-based analytical devices (μPADs) for food and water analysis, which allow easy, rapid and cost-effective point-of-need screening of the targets. This paper reviews recently reported μPADs that incorporate different detection methods such as colorimetric, electrochemical, fluorescence, chemiluminescence, and electrochemiluminescence techniques for food and water analysis.

/pdf/advances-in-microfluidic-paper-based-analytical-devices-for-4wde6scp5y.pdf

Advances in Microfluidic Paper-Based Analytical Devices for Food and Water Analysis.

The extractive technique for protein purification based on two-phase separation in aqueous micellar solutions (aqueous micellar two-phase system (AMTPS)) is reviewed. The micellar solution of a nonionic surfactant, such as polyoxyethyl-ene alkyl ether, which is most frequently used for protein extraction, separates into two phases upon heating above its cloud point. The two phases consist of a surfactant-depleted phase (aqueous phase) and a surfactant-rich phase. Hydrophilic proteins are partitioned to the aqueous phase and hydrophobic membrane proteins are extracted into the sur-factant-rich phase. Because of the methodological simplicity and rapidity, this technique has become an effective means, and thus has been widely used for the purification and characterization of proteins. In contrast to polyoxyethylene alkyl ether, micellar solutions of a zwitterionic surfactant, such as alkylammoniopropyl sulfate, separate below the critical temperature. Alkylglucosides can also separate into two phases upon adding water-soluble polymers. Recently, these two-phase systems have been exploited for protein separation. Additionally, hydrophobic affinity ligands, charged polymers, and ionic surfactants have been successfully used for controlling the extractability of proteins in AMTPS.

/pdf/aqueous-micellar-two-phase-systems-for-protein-separation-5ab0p0s1e0.pdf

Aqueous Micellar Two-Phase Systems for Protein Separation

The precise size control of the lipid nanoparticle (LNP)-based nanodrug delivery system (DDS) carriers, such as 10 nm size tuning of LNPs, is one major challenge for the development of next-generation nanomedicines. Size-controlled LNPs would realize size-selective tumor targeting and deliver DNA and RNA to target tumor tissues effectively by passing through the stromal cells. Herein, we developed a baffle mixer device named the invasive lipid nanoparticle production device, or iLiNP device for short, which has a simple two-dimensional microchannel and mixer structure, and we achieved the first reported LNP size tuning at 10 nm intervals in the size range from 20 to 100 nm. In comparison with the conventional LNP preparation methods and reported micromixer devices, our iLiNP device showed better LNP size controllability, robustness of device design, and LNP productivity. Furthermore, we prepared 80 nm sized LNPs with encapsulated small interfering RNA (siRNA) using the iLiNP device; these LNPs effectively...

Development of the iLiNP Device: Fine Tuning the Lipid Nanoparticle Size within 10 nm for Drug Delivery.

Lipid nanoparticles (LNPs) or liposomes are the most widely used drug carriers for nanomedicines. The size of LNPs is one of the essential factors affecting drug delivery efficiency and therapeutic efficiency. Here, we demonstrated the effect of lipid concentration and mixing performance on the LNP size using microfluidic devices with the aim of understanding the LNP formation mechanism and controlling the LNP size precisely. We fabricated microfluidic devices with different depths, 11 μm and 31 μm, of their chaotic micromixer structures. According to the LNP formation behavior results, by using a low concentration of the lipid solution and the microfluidic device equipped with the 31 μm chaotic mixer structures, we were able to produce the smallest-sized LNPs yet with a narrow particle size distribution. We also evaluated the mixing rate of the microfluidic devices using a laser scanning confocal microscopy and we estimated the critical ethanol concentration for controlling the LNP size. The critical ethanol concentration range was estimated to be 60-80% ethanol. Ten nanometer-sized tuning of LNPs was achieved for the optimum residence time at the critical concentration using the microfluidic devices with chaotic mixer structures. The residence times at the critical concentration necessary to control the LNP size were 10, 15-25, and 50 ms time-scales for 30, 40, and 50 nm-sized LNPs, respectively. Finally, we proposed the LNP formation mechanism based on the determined LNP formation behavior and the critical ethanol concentration. The precise size-controlled LNPs produced by the microfluidic devices are expected to become carriers for next generation nanomedicines and they will lead to new and effective approaches for cancer treatment.

/pdf/understanding-the-formation-mechanism-of-lipid-nanoparticles-39oi7ws8rm.pdf

Hirofumi Tani

Papers

Micelle-mediated extraction

Advances in Microfluidic Paper-Based Analytical Devices for Food and Water Analysis.

Aqueous Micellar Two-Phase Systems for Protein Separation

Development of the iLiNP Device: Fine Tuning the Lipid Nanoparticle Size within 10 nm for Drug Delivery.

Understanding the formation mechanism of lipid nanoparticles in microfluidic devices with chaotic micromixers.