Browsing by Author "Sugiyama, Teruki"

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A Single Spherical Assembly of Protein Amyloid Fibrils Formed by Laser Trapping
(2017-06-06)
Yuyama, Ken-ichi
;
Ueda, Mariko
;
Nagao, Satoshi
;
Hirota, Shun
;
Sugiyama, Teruki
Protein amyloids have received much attention owing to their correlation with serious diseases and to their promising mechanical and optical properties as future materials. Amyloid formation has been conducted by tuning temperature and chemical conditions, so that its nucleation and the following growth are analyzed as ensemble dynamics. A single spherical assembly of amyloid fibrils of cytochrome c domain-swapped dimer was successfully generated upon laser trapping. The amyloid fibrillar structure was confirmed by fluorescence characterization and electron microscopy. The prepared spheres were further manipulated individually in solution to fabricate a three-dimensional microstructure and a line pattern. Amyloid formation dynamics and amyloid-based microstructure fabrication are demonstrated based on direct observation of a single spherical assembly, which foresees a new approach in amyloid studies.
Assembling and crystallization of amino acids and proteins by intense laser irradiation in solution
(2011-08-28)
Masuhara, Hiroshi
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Sugiyama, Teruki
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Yuyama, Ken-ichi
;
Uwada, Takayuki
;
Miura, Atsushi
Bidirectional polymorphic conversion by focused femtosecond laser irradiation
(2020-06-01)
Wu, Chi-Shiun
;
Yoshikawa, Hiroshi Y.
;
Sugiyama, Teruki
;
交大名義發表
;
應用化學系
We present bidirectional polymorphic conversion of L-phenylalanine by focused femtosecond laser irradiation. When the femtosecond laser beam is focused at an air/solution interface of its unsaturated solution, the plate-like anhydrous crystals are generated from the laser focus. This crystal nucleation is realized by local concentration increase achieved by femtosecond laser trapping, which is the first demonstration of femtosecond laser trapping-induced crystallization. Furthermore, the whisker-like monohydrate crystals are produced by continuing the femtosecond laser irradiation on the surface of the plate-like crystals. On the contrary, when a focused femtosecond laser irradiation is applied to the whisker-like monohydrate crystals, the plate-like crystals are formed, meaning that an unstable phase is successfully produced from a stable phase. The dynamics and mechanism of the bidirectional polymorphic conversion are explained from the viewpoint of the nucleation rate theory considering solution concentration around the surface of laser-induced cavitation bubbles. (c) 2020 The Japan Society of Applied Physics
Bubble generation and molecular crystallization at solution surface by intense continuous-wave laser irradiation
(2018-08-01)
Chen, Jim Jui-Kai
;
Yuyama, Ken-ichi
;
Sugiyama, Teruki
;
Masuhara, Hiroshi
;
應用化學系
We demonstrate bubble generation outside the focus induced by irradiating a focused 1064 nm continuous-wave laser beam into the surface of water and L-phenylalanine H2O solutions. In the former case of water, bubbles stay at positions distant from the focus during the irradiation, and their size and location are controllable by the laser power. In the latter solution, bubbles move outward toward the surrounding area, and subsequently crystallization takes place at the focus. We discuss these behaviors from the viewpoints of the temperature elevation accompanying the decrease in air solubility as well as the optical trapping of L-phenylalanine clusters giving a single crystal. (C) 2018 The Japan Society of Applied Physics
Control of Crystal Polymorph of Glycine by Photon Pressure of a Focused Continuous Wave Near-Infrared Laser Beam
(2010-02-04)
Rungsimanon, Thitiporn
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Yuyama, Ken-ichi
;
Sugiyama, Teruki
;
Masuhara, Hiroshi
;
Tohnai, Norimitsu
Crystal polymorph of glycine is controlled by tuning the power of a linearly polarized continuous wave 1064-nm laser beam. Upon focusing the beam to the air/solution interface of a supersaturated glycine/D(2)O solution, it single crystal is spatiotemporally formed at a focal spot within a few seconds to a few ten of seconds. Fourier transform infrared measurement and single-crystal X-ray crystallographic analysis of the fabricated single crystal reveal that two polymorphs of alpha- and gamma-forms are prepared depending on the laser power. The probability of gamma-form are prepared depending on the laser power. The probability of gamma-form preparation, which is not available under ambient conditions arises upto 50% at 1.3 W laser power after an objective lens. The mechanism of the polymorph control is discussed in view of both photon pressure and local temperature elevation due to laser irradiation at the focal spot.
Crystal Growth and Dissolution Dynamics of L-Phenylalanine Controlled by Solution Surface Laser Trapping
(2018-11-01)
Yuyama, Ken-ichi
;
Chiu, Ding-Shiang
;
Liu, Yen-En
;
Sugiyama, Teruki
;
Masuhara, Hiroshi
We present sequential behavior of nucleation, growth, and dissolution of an L-phenylalanine plate-like crystal which is induced by a focused continuous-wave near-infrared laser beam in unsaturated solution. Upon the laser irradiation into the air/solution interface, the single crystal is generated from the focus and continuously grows two-dimensionally while being trapped by the laser. The crystal growth is stopped when the laser power is decreased. The crystal size is kept constant for a certain time period, and then the crystal starts dissolution. The dissolution is also induced by moving the crystal from the focus at the air/solution interface. When the crystal is shifted far from the original position where the crystallization is induced, the crystal starts dissolution at a certain distant position. Based on the demonstrations of the crystal size change during the laser manipulation, we conclude that the L-phenylalanine crystal is surrounded by a highly concentrated domain of a few hundreds of micrometers consisting of L-phenylalanine liquid-like clusters.
Crystal Growth of Glycine Controlled by a Focused CW Near-infrared Laser Beam
(2009-05-05)
Sugiyama, Teruki
;
Adachi, Takuji
;
Masuhara, Hiroshi
;
應用化學系
;
應用化學系分子科學碩博班
Crystal growth of glycine was accelerated just by focusing a CW 1064-nm laser beam at a position adjacent to a spontaneously generated glycine crystal in D(2)O. Its rate depended on the distance between the crystal and the focal spot. Interesting crystal growth and dissolution were found, which is considered to be due to Ostwald ripening,
Crystal Growth of Lysozyme Controlled by Laser Trapping
(2014-01-01)
Tu, Jing-Ru
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Miura, Atsushi
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Yuyama, Ken-ichi
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Masuhara, Hiroshi
;
Sugiyama, Teruki
We demonstrate the growth of a tetragonal crystal of hen egg-white lysozyme (HEWL) in D2O buffer solution controlled by laser trapping with a focused continuous-wave (CW) near-infrared (NIR) laser beam. The focal spot was located at 10 mu m away from the edge of the target crystal that was generated spontaneously, and the crystal growth was observed although the focal spot size was much smaller than the distance. The growth rate of (101) and {110} faces of the tetragonal crystal was examined with various laser powers and polarizations. The rate observed under the irradiation was much different from those in spontaneous growth, namely, the growth rate of the {1 10} face showed a large decrease or increase depending on the irradiation time. The dynamics and mechanism of this unusual crystal growth behavior is discussed from the viewpoint of a large stable domain formation of the HEWL liquidlike clusters through liquid nucleation and growth and by considering the anisotropy of the cluster domain.
Crystallization in Unsaturated Glycine/D(2)O Solution Achieved by Irradiating a Focused Continuous Wave Near Infrared Laser
(2010-11-01)
Rungsimanon, Thitiporn
;
Yuyama, Ken-ichi
;
Sugiyama, Teruki
;
Masuhara, Hiroshi
;
應用化學系
The crystallization of glycine in unsaturated solution is made possible by laser trapping of its molecular clusters due to photon pressure of a focused continuous wave near-infrared laser beam. Always one single crystal is spatiotemporally formed at a focal spot, and then it undergoes dissolution, eventually leading to repetitive crystallization and dissolution. The polymorph characterization of the crystal formed in unsaturated solution confirmed the gamma-form, which is not obtainable by conventional crystallization methods. The preparation probability of the gamma-form compared to the alpha-form is much higher than that in the supersaturated solution.
Crystallization in Unsaturated Glycine/D2O Solution Achieved by Irradiating a Focused Continuous Wave Near Infrared Laser
(2010-11-01)
Rungsimanon, Thitiporn
;
Yuyama, Ken-ichi
;
Sugiyama, Teruki
;
Masuhara, Hiroshi
;
應用化學系
The crystallization of glycine in unsaturated solution is made possible by laser trapping of its molecular clusters due to photon pressure of a focused continuous wave near-infrared laser beam. Always one single crystal is spatiotemporally formed at a focal spot, and then it undergoes dissolution, eventually leading to repetitive crystallization and dissolution. The polymorph characterization of the crystal formed in unsaturated solution confirmed the gamma-form, which is not obtainable by conventional crystallization methods. The preparation probability of the gamma-form compared to the alpha-form is much higher than that in the supersaturated solution.
Dynamics and Mechanism of Laser Trapping-Induced Crystal Growth of Hen Egg White Lysozyme
(2015-10-01)
Tu, Jing-Ru
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Yuyama, Ken-ichi
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Masuhara, Hiroshi
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Sugiyama, Teruki
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應用化學系
We propose the dynamics and mechanism of laser trapping-induced crystal growth of hen egg-white lysozyme (HEWL). A continuous-wave near-infrared laser beam is used as a trapping light source and focused at a point 10 mu m away from a target tetragonal HEWL crystal that is spontaneously generated in solution. Laser trapping of HEWL liquid-like clusters in solution increases local concentration in the focus, where the free motion and orientation of the clusters are strongly restricted, and the clusters show high rigidity and ordering. The cluster association and reorientation at the micrometer-sized focus is evolved to a large highly concentrated domain of the clusters, where the specific target crystal is grown. Initially, the high rigidity and ordering of the clusters strongly suppress the crystal grow rate compared to spontaneous crystal growth. Continuous laser trapping at the of the initially formed domain, however, leads to the transition to another domain with different concentration, rigidity, and ordering of the clusters, which surprisingly enhances the crystal growth rate. More interestingly, the clusters in both domains have anisotropic features reflecting the laser polarization direction, which also contributes to the crystal growth.
Evolving Crystal Morphology of Potassium Chloride Controlled by Optical Trapping
(2020-03-26)
Cheng, An-Chieh
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Masuhara, Hiroshi
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Sugiyama, Teruki
;
交大名義發表
;
應用化學系
Dynamic morphology evolution of potassium chloride (KCl) crystals was demonstrated by surface optical trapping with a focused continuous-wave near-infrared laser. Optical trapping at an air/solution interface triggered the crystallization, and then, the dynamic change in crystal morphology was observed in real time. We observed three different crystal morphologies of needle, rectangle, and cubic at the early stage of crystallization. As the laser power increases, the probability of generation of a cubic crystal increases, especially upon the irradiation with linear polarization. We also found laser polarization-dependent morphology evolution by the continuous irradiation to the generated crystals. Upon linearly polarized laser irradiation, the stepwise morphology evolves from needle to rectangle, and eventually to cubic, which is an equilibrium shape of KCl crystals. Meanwhile, circularly polarized laser irradiation only induced morphology evolution from needle to rectangle, without morphology change into cubic, because the rectangle crystal was dissolved while the crystal was rotating. It was made possible to observe such a unique morphological evolution due to the spatiotemporal controllability of our crystallization method. The dynamics and mechanism of these intriguing phenomena are discussed from the perspective of a dense cluster domain formed by optical trapping before nucleation.
Femtosecond Laser Trapping Dynamics of Nanoparticles: A Single Transient Assembly Formation Leading to Their Directional Ejection
(2018-06-28)
Chiang, Wei-Yi
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Usrnan, Anwar
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Sugiyama, Teruki
;
Hofkens, Johan
;
Masuhara, Hiroshi
We investigated femtosecond laser trapping dynamics of silica nanoparticles with different hydrophobic surface properties. We demonstrated that the hydrophobic surface on the silica nanoparticles facilitates mutual association of the nanoparticles in the optical trapping site. Such association of optically trapped nanoparticles is a prerequisite to induce their directional ejection away from the trapping site. The directional ejection of the optically trapped nanoparticles is most probably due to asymmetric three-dimensional ejecting forces generated by the electromagnetic interaction between transient assembly in the focal spot and the incident pulses. These findings provide important insights into the directional ejection of nanoparticles from the trapping site in the femtosecond laser trapping, and this physicochemical phenomenon is controlled by both the trapping laser and material properties.
Femtosecond laser trapping, assembling, and ejection dynamics of dielectric nanoparticles in solution
(2018-01-01)
Masuhara, Hiroshi
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Chen, Jim Jui-Kai
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Chiang, Wei-Yi
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Usman, Anwar
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Sugiyama, Teruki
We elucidated femtosecond laser trapping dynamics of Rayleigh particles by modifying the surface property of nanoparticles and changing the viscosity. Through bright field, dark field and backscattering images, we monitored ejection behavior of nanoparticles which takes place in the direction perpendicular to laser polarization and switched from one side to the other. For very hydrophobic nanoparticle, we succeeded in observing directly a transient assembly and confirmed that its formation is responsible to the directional ejection. Also the trapping dynamics was compared for femtosecond and continuous-wave lasers in highly viscous solvent, which gives a new viewpoint for understanding femtosecond laser trapping mechanism.
Femtosecond-Laser-Enhanced Amyloid Fibril Formation of Insulin
(2017-08-22)
Liu, Tsung-Han
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Yuyama, Ken-ichi
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Hiramatsu, Takato
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Yamamoto, Naoki
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Chatani, Eri
Femtosecond (fs)-laser-induced crystallization as a novel crystallization technique was proposed for the first time by our group, where the crystallization time can be significantly shortened under fs laser irradiation. Similarly, we have further extended our investigation to amyloid fibril formation, also known as a nucleation-dependence process. Here we demonstrate that the necessary time for amyloid fibril formation can be signifiCantly shortened by fs laser irradiation, leading to favorable enhancement. The enhancement was confirmed by both spectral measurements and direct observations of amyloid fibrils. The thioflavin T fluorescence intensity of laser-irradiated solution increased earlier than that of the control solution, and such a difference was simultaneously revealed by ellipticity changes. At the same time before intensity Saturation in fluorescence, the number of amykid fibrils obtained under laser irradiation was generally mote than that in the control. Solution. Besides, such an enhancement is correlated to the laser power threshold of cavitation bubbling. Possible mechanisms are proposed by referring to fs-laser-induced crystallization and ultrasonication-induced amyloid fibril formation.
Formation Mechanism and Fluorescence Characterization of a Transient Assembly of Nanoparticles Generated by Femtosecond Laser Trapping
(2019-11-14)
Chiang, Wei-Yi
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Chen, Jim Jui-Kai
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Usman, Anwar
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Kudo, Tetsuhiro
;
Xia, Kangwei
Femtosecond (fs) laser trapping of dielectric nanoparticles displays a unique trapping and directional ejection phenomenon, which is never observed in continuous-wave (cw) laser trapping. We studied the fs laser trapping and considered its dynamics and mechanism in terms of gathering, association, and ejection of nanoparticles. By tuning solution viscosity through adding ethylene glycol, the trapping behavior by fs and cw lasers are examined and compared with each other. The viscous solution slows down the diffusional and rotational movement of nanoparticles and increases the chance of nanoparticle assembly in the trapping site, which eventually leads to the novel ejection. We took advantage of fluorescence measurement to confirm the formation of the nanoparticle assembly during fs laser trapping. A red emission irregularly appeared in the fluorescence supports the transient assembly formation in the molecular level.
Formation, Dissolution, and Transfer Dynamics of a Millimeter-Scale Thin Liquid Droplet in Glycine Solution by Laser Trapping
(2012-03-29)
Yuyama, Ken-ichi
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Rungsimanon, Thitiporn
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Sugiyama, Teruki
;
Masuhara, Hiroshi
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應用化學系
The formation, dissolution, and transfer of a millimeter-scale dense liquid droplet are demonstrated by focusing a CW near-infrared laser beam into a thin film of glycine solution in heavy water. The entire process is investigated by directly monitoring the temporal change in the two-dimensional surface profile using a laser displacement meter. Upon laser irradiation, the surface depression is initially induced by laser heating, followed by the formation of the shallow convex-shaped droplet around the focal spot, in which the droplet is always in contact with the surrounding solution through the ultrathin solution layer. After the laser is switched off, the dissolution occurs through the recovery from the ultrathin layer toward the original solution film. When the laser is set to the outside of the droplet, the solution depression is similarly induced, and subsequently the droplet starts moving toward the focal spot. These processes are summarized and discussed in view of laser-induced effects of concentration increase and temperature elevation.
"Freezing" of NaClO3 Metastable Crystalline State by Optical Trapping in Unsaturated Microdroplet
(2018-02-01)
Niinomi, Hiromasa
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Sugiyama, Teruki
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Miyamoto, Katsuhiko
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Omatsu, Takashige
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應用化學系
We reversibly controlled phase conversion between a microdroplet of a NaClO3 unsaturated aqueous solution and a metastable single crystal, which is usually a short-lived phase in spontaneous crystallization, simply by irradiating a tightly focused visible continuous-wave (CW) laser to the microdroplet. The laser irradiation allowed the metastable crystal to generate and stably grow without a polymorphic transformation. This successful metastable phase control is attributed to the combination of the advantage of optical trapping-induced nucleation that nucleation takes place from unsaturated mother solution and the advantage of microdroplet method, which suppresses additional nucleation leading to the transformation. In situ observation shows the crystal dissolves when the laser irradiation is stopped, whereas the laser irradiation stabilizes the crystal even if the size of the crystal becomes larger than that of focal spot. These observations indicate that a change in the relative magnitudes of chemical potentials between solution/crystalline phases. This change is possibly promoted via crystal growth by trapping of crystalline clusters in optical potential well formed on a crystal surfaces originating from "light propagation" through the crystal. Our results shed a light not only on polymorph control but also on a method to prepare a longer-lived achiral precursor for analysis on achiral chiral transition by "freezing" a kinetic pathway of chiral crystallization.
Glycine Crystallization in Solution by CW Laser-Induced Microbubble on Gold Thin Film Surface
(2012-03-01)
Uwada, Takayuki
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Fujii, Sho
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Sugiyama, Teruki
;
Usman, Anwar
;
Miura, Atsushi
We have developed a novel laser-induced crystallization method utilizing local heat-induced bubble/water interface. Continuous laser beam of 1064 nm is focused on a gold nanoparticles thin film surface covered with glycine supersaturated aqueous solution. Light absorption of the film due to localized plasmon resonance caused local heating at the focal position and produced a single thermal vapor microbubble, which generated thermal gradient followed by convection flow around the bubble and eventually induced glycine crystallization and growth. The crystallization mechanism is discussed by considering gathering and accumulating molecules around the bubble/water interface assisted by convection flow and temperature jump.
Growth Promotion of Targeted Crystal Face by Nanoprocessing via Laser Ablation
(2019-10-10)
Wu, Chi-Shiun
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Ikeyama, Jun
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Nakabayashi, Seiichiro
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Sugiyama, Teruki
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Yoshikawa, Hiroshi Y.
Control of crystal shape is an indispensable step for various applications of crystalline products. However, obtaining the desired crystal shape by conventionally tuning environmental conditions (temperature, additives, etc.) cannot always be reached. Recently, we have developed an innovative approach for spatiotemporal control of crystal growth of proteins and amino acids by locally modifying crystal structure (e.g., formation of screw dislocations) via femtosecond (fs) laser ablation. In this work, to clarify the appropriate laser condition for controlling the shape of single crystals with minimized damage, we first systematically investigated the dependence of pulse duration on laser ablation and crystal growth of L-phenylalanine (L-Phe). By using a laser system with tunable pulse durations from fs to nanoseconds (ns), we found fs laser ablation can offer nanometer-sized, sharp etching of which diameter was smaller than the diffraction limit. By utilizing such nanoprocessing via fs laser ablation for promoting the growth of a targeted crystal face, we successfully demonstrated the preparation of a bulky crystal of L-Phe, which is difficult to be obtained by conventional crystallization methods.