Naoto Isozaki
Kyoto University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Naoto Isozaki.
Scientific Reports | 2015
Naoto Isozaki; Suguru Ando; Tasuku Nakahara; Hirofumi Shintaku; Hidetoshi Kotera; Edgar Meyhofer; Ryuji Yokokawa
One of challenges for using microtubules (MTs) driven by kinesin motors in microfluidic environments is to control their direction of movement. Although applying physical biases to rectify MTs is prevalent, it has not been established as a design methodology in conjunction with microfluidic devices. In the future, the methodology is expected to achieve functional motor-driven nanosystems. Here, we propose a method to guide kinesin-propelled MTs in multiple directions under an electric field by designing a charged surface of MT minus ends labeled with dsDNA via a streptavidin-biotin interaction. MTs labeled with 20-bp or 50-bp dsDNA molecules showed significantly different trajectories according to the DNA length, which were in good agreement with values predicted from electrophoretic mobilities measured for their minus ends. Since the effective charge of labeled DNA molecules was equal to that of freely dispersed DNA molecules in a buffer solution, MT trajectory could be estimated by selecting labeling molecules with known charges. Moreover, the estimated trajectory enables to define geometrical sizes of a microfluidic device. This rational molecular design and prediction methodology allows MTs to be guided in multiple directions, demonstrating the feasibility of using molecular sorters driven by motor proteins.
bioRxiv | 2017
Naoto Isozaki; Hirofumi Shintaku; Hidetoshi Kotera; Taviare L. Hawkins; Jennifer L. Ross; Ryuji Yokokawa
Molecular shuttles can be autonomously sorted by designing electromechanical properties of microtubules. Kinesin-driven microtubules have been focused on to serve as molecular transporters, called “molecular shuttles,” to replace micro/nanoscale molecular manipulations necessitated in micro total analysis systems. Although transport, concentration, and detection of target molecules have been demonstrated, controllability of the transport directions is still a major challenge. Toward broad applications of molecular shuttles by defining multiple moving directions for selective molecular transport, we integrated a bottom-up molecular design of microtubules and a top-down design of a microfluidic device. The surface charge density and stiffness of microtubules were controlled, allowing us to create three different types of microtubules, each with different gliding directions corresponding to their electrical and mechanical properties. The measured curvature of the gliding microtubules enabled us to optimize the size and design of the device for molecular sorting in a top-down approach. The integrated bottom-up and top-down design achieved separation of stiff microtubules from negatively charged, soft microtubules under an electric field. Our method guides multiple microtubules by integrating molecular control and microfluidic device design; it is not only limited to molecular sorters but is also applicable to various molecular shuttles with the high controllability in their movement directions.
international conference on micro electro mechanical systems | 2015
Naoto Isozaki; Hirofumi Shintaku; Hidetoshi Kotera; Edgar Meyhofer; Ryuji Yokokawa
We propose a method to control gliding directions of kinesin-propelled microtubules (MTs) corresponding to their flexural rigidity (EI). We prepared two kinds of MTs having different EI and their trajectories within an electric field were clearly separated. Therefore, this study demonstrated the EI-altered MTs can be workhorses to sort/concentrate various combinations of target molecules loaded on MTs.
Biophysical Journal | 2017
Naoto Isozaki; Hirofumi Shintaku; Hidetoshi Kotera; Taviare L. Hawkins; Jennifer L. Ross; Ryuji Yokokawa
Biophysical Journal | 2016
Naoto Isozaki; Scott Erickson; Shintaku Hirofumi; Hidetoshi Kotera; Taviare L. Hawkins; Jennifer L. Ross; Ryuji Yokokawa
電気学会論文誌. E, センサ・マイクロマシン部門誌 = IEEJ transactions on sensors and micromachines | 2014
Tasuku Nakahara; Naoto Isozaki; Suguru Ando
Seibutsu Butsuri | 2014
Naoto Isozaki; Suguru Ando; Hirofumi Shintaku; Hidetoshi Kotera; Edgar Meyhofer; Ryuji Yokokawa
Ieej Transactions on Sensors and Micromachines | 2014
Tasuku Nakahara; Naoto Isozaki; Suguru Ando; Nagendra Kumar Kamisetty; Hirofumi Shintaku; Hidetoshi Kotera; Ryuji Yokokawa
international conference on solid state sensors actuators and microsystems | 2013
Naoto Isozaki; Tatsushi Nakahara; Shin Ando; Nagendra Kumar Kamisetty; Hirofumi Shintaku; Hidetoshi Kotera; Edgar Meyhofer; Ryuji Yokokawa
The Proceedings of Mechanical Engineering Congress, Japan | 2013
Suguru Ando; Naoto Isozaki; Tasuku Nakahara; Hirofumi Shintaku; Hidetoshi Kotera; Ryuji Yokokawa