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} </style> </head> <BODY> <div id="biomodlink"> <<a href="http://openwetware.org/wiki/Biomod">BIOMOD</a>|<a href="http://openwetware.org/wiki/Biomod/2012">2012</a>|Titech Nano-Jugglers </div> <div id="header"> <div id="navigation"> <div id="menu"> <ul> <li><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers"> Home </a></li> <li><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers/Team/Students"> Team </a></li> <li><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers/Project"> Project </a></li> <li><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers/Results">Results & Methods</a></li> <li class="ach"><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers/Achievements"> Achievements </a> <li class="sup"><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers/Protocols"> Suppl. Info. </a></li> <li class="none"><a href="http://openwetware.org/wiki/Biomod/2012/Titech/Nano-Jugglers/Acknowledgement"> Acknowledgements </a></li> </ul> </div> </div> </div> </BODY> </html>

Results

Construction of Biomolecular Rocket

We constructed Biomolecular Rocket composed of a micrometer-sized body and many catalytic engines. The catalytic engines were conjugated to the body using DNA-bead linkers in a spatially selective manner.

Shown in detail below

<html><body><A href=#1._Power_supply_for_the_rail-free_movement_of_the_Biomolecular_Rocket title="Rail-free"><img src="http://openwetware.org/images/7/7f/Rail-free%E3%80%80movement_kinesin.jpg" border=0 width=310 height=220></a></body></html>
Power supply for the rail-free movement of the Biomolecular Rocket

<html><body><A href=#2._Realization_of_the_high-speed_movement_of_the_Biomolecular_Rocket title="High-speed"><img src="http://openwetware.org/images/8/89/High-speed_movement.jpg" border=0 width=310 height=220></a></body></html>
Realization of high-speed movement of the Biomolecular Rocket

<html><body><A href=#3._Introduction_of_a_photo-switchable_DNA_system_for_the_directional_control title="Control"><img src="http://openwetware.org/images/d/dd/Control_image.jpg" border=0 width=310 height=220></a></body></html>
Introduction of a photo-switchable DNA system for the directional control

We realized the rail-free movement by power generation with catalytic reactions of platinum and catalase.

Shown in detail below

We realized the high-speed movement by power generation with catalytic reactions of platinum and catalase, and analyzed the speed.
We carried out numerical simulations of the high-speed movement of the Biomolecular Rockets.

Shown in detail below

We developed a photo-switchable DNA system for controlling of the Bimolecular Rocket using UV light irradiation.
We investigated directional control of the Biomolecular Rocket in the simulations.

Shown in detail below

0. Construction of Biomolecular Rocket

<html><body>We constructed Biomolecular Rocket with a microbead, catalysts, and designed DNAs.</body></html>

Biomolecular Rocket is composed of a micrometer-sized body and many catalytic engines. The body consists of a microbead with a diameter of 10 μm, and catalytic engines consist of platinum nanoparticles or catalase molecules. The catalytic engines are conjugated to the body using a DNA-based linker in a spatially selective manner.
We constructed the Biomolecular Rocket through the following four steps.

<li>The microbead body was selectively coated by vapor deposition of metals (Au and Cr). <li>We designed DNA sequences for spatially-selective hybridization of catalytic engines. <li>The DNA molecules were conjugated to a designated metal surface of the microbead body. <li>Catalyst engines were attached to the microbead body with selective hybridization of DNAs we designed.</ol></body></html>

>>see more methods

0.1. Selective coating of the body

<html><body>We succeeded in selective coating of a micrometer-sized bead by vapor deposition of Au and Cr.</body></html>

>>see more methods

Figure 0.1a, b and c are microscope images of 40 μm microbeads. Figure 0.1a shows microbeads before vapor deposition of metals. Figure 0.1b shows microbeads after vapor deposition of Au (gold) on the microbeads. Figure 0.1c shows microbeads after additional vapor deposition of Cr (chromium) on the Au-deposited microbeads. The microbeads had three types of surface areas because the angular alignment of the beads was changed when Cr was deposited on the Au-deposited microbeads.

Similarly, Figure 0.1e, f and g are microscope images of 10 μm microbeads. Figure 0.1e shows microbeads before vapor deposition of metals. Figure 0.1f shows microbeads after vapor deposition of Au on the microbeads. Figure 0.1g shows microbeads after additional vapor deposition of Cr on the Au-deposited microbeads. The 10 μm microbeads probably had three types of surface areas. From these results, we conclude that selective coating of microbeads for the Biomolecular Rocket was achieved.

<html><body><nobr>40 μm silica beads</nobr></body></html>	a	b	c
<html><body><nobr>10 μm polystyrene beads</nobr></body></html>	d	e	f
<html><body><nobr>Image of micro-beads</nobr></body></html>	<html><body><img src="http://openwetware.org/images/d/d5/Polystyrene.jpg" border=0 width=240 height=180></body></html>	<html><body><img src="http://openwetware.org/images/4/41/After_first_deposition.jpg" border=0 width=240 height=180></body></html>	<html><body><img src="http://openwetware.org/images/3/30/After_second_deposition.jpg" border=0 width=240 height=180></body></html>
Fig. 0.1 Selective coating of micro-beads by vapor deposition.

0.2. Design of linker DNA strands

<html><body>We designed DNA sequences for the linkers to attach catalytic engines to the microbead body.</body></html>

>>see more methods

We designed two kinds of DNA sequences with different stability. One is DNA sequence L. This sequence forms a very stable duplex with its complementary sequence L^* at a room temperature. Another is DNA sequence S. The duplex of DNA sequence S and S^* has less stability than DNA sequence L and L^* but is stable at a room temperature.

DNA sequence L <html><body><nobr>5’-CGTCTATTGCTTGTCACTTCCCC-3'  </nobr></body></html>	DNA sequence S <html><body><nobr>5’-AATACCCAGCC-3’  </nobr></body></html>
DNA sequence L^* <html><body><nobr>5'-GGGGAAGTGACAAGCAATAGACG-3'  </nobr></body></html>	DNA sequence S^* <html><body><nobr>5’-GGCTGGGTATT-3'  </nobr></body></html>

Figure 0.2a and 0.2b show calculated melting profiles of duplexes L-L^* and S-S^*, respectively. Calculated melting temperatures of these duplexes were higher than a room temperature.

a	b
Fig. 0.2. (a) The melting profile of duplex L-L^. (b) The melting profile of duplex S-S^. RT and T_m indicate a room temperature (24°C) and a melting temperature, respectively. We calculated the melting profiles using NUPACK software.

0.3. Selective DNA conjugation to the microbead body of Biomolecular Rocket

0.3.1. Selective conjugation of DNA to polystyrene surface area

<html><body>We succeeded in selective DNA conjugation to the polystyrene surface area of the microbead body.</body></html>

>>see more methods

We conjugated amino-modified DNA sequence L^* to the calboxylated polystyrene surface area of the microbead body with amide binding. To investigate the selective conjugation of L^*, we hybridized a fluorophore-modified DNA sequence L with L* on the body and observed the DNA-conjugated microbead bodies.

Figure 0.3.1a, b, and c are bright-field microscope images of selectively-coated microbead bodies (10 μm in diameter). Figure 0.3.1a', b', and c' are fluorescence microscope images of the selectively-coated microbead bodies. Figure 0.3.1a and a' shows selectively DNA-L^*-conjugated microbeads with fluorophore-modified DNA L. Fluorescence of L was observed only where the polystyrene surface was exposed after the vapor deposition of metal. Figure 0.3.1b and b' shows selectively DNA-L^*-conjugated microbeads without fluorophore-modified DNA L, and no fluorescence was observed. Figure 0.3.1c and c' shows non-DNA-conjugated microbeads with fluorophore-modified DNA L, and no fluorescence was observed. From these results, we conclude that selective conjugation of DNA L^* to polystyrene surface area of the microbead bodies was achieved.

<html><body><nobr>Bright-field microscope images</nobr></body></html>	a	b	c
<html><body><nobr>Fluorescence microscope images</nobr></body></html>	a'	b'	c'
<html><body><nobr>Experimental conditions<nobr></body></html>	<html><body><img src="http://openwetware.org/images/d/d3/EDACBEADS1.JPG" border=0 width=220 height=120></a></body></html>	<html><body><img src="http://openwetware.org/images/3/38/EDACBEADS2.JPG" border=0 width=220 height=120></a></body></html>	<html><body><img src="http://openwetware.org/images/2/23/EDACBEADS3.JPG" border=0 width=220 height=120></a></body></html>
Fig. 0.3.1 Microscope images of the microbead bodies of Biomolecular Rocket. (a) and (a') Selectively DNA-conjugated microbeads with complementary fluorophore-modified DNA. (b) and (b') Selectively DNA-conjugated microbeads without complementary fluorophore-modified DNA. (c) and (c') non-DNA-conjugated microbeads with complementary fluorophore-modified DNA.

0.3.2. Selective conjugation of DNA to metal surface area

<html><body>We succeeded in selective DNA conjugation to the Au surface area of the microbead body.</body></html>

>>see more methods

We conjugated thiol-modified DNA sequence S^* to the Au surface area of the microbead body with Au-thiol bonding. To confirm the selective conjugation of S^* to an Au surface, we observed an Au-deposited cover glass after DNA conjugation instead of selectively Au-coated microbeads after DNA conjugation. We investigated the wetting properties of the Au surface before and after DNA conjugation because the wetting investigation showed the selective conjugation of DNA more clearly than the fluorescence observation like Fig. 0.3.1.

Figure 0.3.2a shows the Au glass plate with a non-DNA spot (1), a non-thiol-modified DNA spot (2), and a thiol-modified DNA spot (3). Only at the spot (3), residual water was observed. The water remained by the wetting property of the spot (3); the higher wetting property of spot (3) than those of spots (1) and (2) was expected to be caused by the Au surface with thiol-modified DNA conjugation. Therefore, we conclude that selective conjugation of thiol-modified DNA to the Au surface area of the microbead body was also achieved.

a	b
c <html><body><img src="http://openwetware.org/images/1/1a/Auplate1.jpg" border=0 width=800 height=150></a></body></html>
Fig. 0.3.2. (a) An Au glass plate with a non-DNA spot (1), a non-thiol-modified DNA spot (2), and a thiol-modified DNA spot (3). (b) A layout drawing of the spots (1)-(3). (c) Experimental condition for the spots (1)-(3).

0.4. Catalyst attachment with DNA hybridization

<html><body>Catalyst engines are attached to the microbead body of Biomolecular Rocket with DNA hybridization reactions between L and L*, and S and S*.</body></html>

>>see more methods

From the results of sections 0.1 and 0.3, a selectively DNA-conjugated microbead body of Biomolecular Rocket is constructed. In addition, we prepared catalytic engines with DNA-tag sequences (L and S) that are complementary to the DNA sequences (L^* and S^*) on the body. Therefore, by mixing the DNA-tagged catalytic engines and selectively DNA-conjugated body, Biomolecular Rocket would be constructed in a self-assembled manner. Experiments are currently in progress.

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<html><body>1. Power supply for the rail-free movement of the Biomolecular Rocket</body></html>

<html><body>We achieved the power supply for the rail-free movement of the Biomolecular Rocket.</body></html>

We utilized H₂O₂ for fuel and catalysts of H₂O₂ for catalytic engines to realize the rail-free movement of the Biomolecular Rocket. Catalysts such as platinum and catalase catalyze the decomposition of H₂O₂ into H₂O and O₂; emitted bubbles of O₂ launch Biomolecular Rocket.

Here, we investigated the following points to realize the power supply for the rail-free movement of the Biomolecular Rocket.

<li>We found that catalase molecules as catalytic engines could emit sufficient amount of bubbles for the rail-free movement. <li>We found that platinum particles as a catalytic engines could emit sufficient amount of bubbles for rail-free movement. <li>We found that the H2O2 did not affect the stability of DNA linkers for attaching catalytic engines to the body in the H2O2 solution. </ol></body></html>

1.1. Power supply for rail-free movement by using catalase catalytic engine

<html><body>We succeeded in the rail-free movement by O2 bubble emission with catalase.</body></html>

We utilized the catalase for catalytic engines, which catalyzes the decomposition of H₂O₂ into H₂O and O₂. Here, we conjugated the catalase to the polystyrene area of a microbead with a hemispherical Au surface and a hemispherical polystyrene surface (Fig. 1.1).

>>see more methods

Movie 1.1 shows the rail-free movement of a 10 μm microbead with a hemispherical Au surface and a hemispherical polystyrene surface by O₂ bubble emission with catalase. The 10 μm beads without catalase did not move at all (Movie 1.2). Thus, we conclude that we succeeded in the rail-free movement by O₂ bubble emission with catalase.

Fig. 1.1 Image of a microbead with a hemispherical Au surface and a hemispherical polystyrene surface in 3% H₂O₂ solution.

Movie. 1.1 The real-time video of the moving 10 μm bead with a catalase-conjugated hemisphere area in 3% H₂O₂ solution.

1.2. Power supply for rail-free movement by using platinum catalytic engine

<html><body>We achieved bubble emissions with platinum micro-particles in solution of H2O2.</body></html>

We provided 1 μm platinum particles, and Cr coating to create platinum hemispherical area. Then added 3% H₂O₂ solution and observed their movement.

>>see more methods

Movie 1.2 reveals the catalytic reaction of 3% H₂O₂ and 1 μm beads that have platinum hemispherical area. We can recognize that bubbles are emitted in H₂O₂ solution. These bubbles are emitted from 1 μm beads that have platinum hemispherical area by decomposing H₂O₂. From this result, we conclude that power supply for rail-free movement by using platinum catalytic engine was achieved.

Fig. 1.2 Image of a microbead with a hemispherical Cr surface and a hemispherical platinum surface in 3% H₂O₂ solution.

Movie. 1.2 Image of the catalytic reaction of 3% H₂O₂ and 1 μm beads that have platinum hemispherical area.

1.3. DNA hybridization in solution of H₂O₂

<html><body>We revealed that diluted H2O2 solutions did not affect DNA hybridization and a H2O2 solution was suitable for a fuel for the Biomolecular Rocket. </body></html>

>>see more methods

We confirmed that DNA duplexes were stably formed in diluted H₂O₂ solutions by the native polyacrylamide gel electrophoresis (PAGE). Figure 1.3 shows the gel image of the PAGE. As shown in the lanes 1-3, a double-stranded DNA was formed in 1% and 5% H₂O₂ solutions.

Fig. 1.3 A gel image of a native PAGE of DNA in H₂O₂ solutions. Lanes 1-3, 8: a double stranded DNA (D+R) in diluted H₂O₂ solutions eith concentrations 0% (lanes 1 and 8), 1% (lane 2), and 5% (lane 3). In lanes 4-7, single stranded DNAs in 0% and 5% H₂O₂ solutions were shown. DNA sequences R and D are shown at the upper right of the image.

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2. Realization of the high-speed movement of the Biomolecular Rocket

<html><body>We confirmed the high-speed movement of the Biomorecular Rocket by bubble emission.</body></html>

Catalytic engines emit large amount of bubbles, and thus, supply powerful driving force to the Biomolecular Rocket. By the analyses of the movement of platinum particles and numerical simulations, we found that the speed of the Biomolcular Rocket was faster than that of kinesin. We carried out the experiments and simulations as follows.

<li>Observations of the movement of platinum particles using a high-speed camera and analyses of the speed <li>Numerical simulations of the movement of the Biomolecular Rocket</ol></body></html>

2.1. Power supply for the high-speed movement with platinum catalytic engines

<html><body>We succeeded in high speed movement with platinum catalytic engines.</body></html>

>>see more methods and full length movie

Movie 2.1.1a shows the movement of 0.15-0.40 μm platinum particles in 3% H₂O₂ solution. Movie 2.1.1b is the movement of platinum particles observed by a high-speed camera (the upper left of the movie) and its analyzed results (the right of the movie). The analyzed results show the values of acceleration (top), velocity (the second from the top), coordinate x (third), and coordinate y (bottom) of platinum movement. From the results, we found the relationships between the growth of bubble radius and the speed of platinum. Using the relationships and the kinetic parameters, we did numerical simulations of the movement of the Biomolecular Rocket (see Section 2.2).

Figure. 2.1.2 shows the graph of the mean square displacement of the platinum particle. We can calculate mean speed of platinum particle by making a quadratic curve fitting and calculating square root of coefficient of the curve. We calculated that the value of quadratic coefficient was 115.5 mm²/s², and the average speed was calculated as 10.7 mm/s. Assuming that kinesin moves at 1μm/s, Platinum particles in H₂O₂ solution can moved at about 10,000 time’s faster speed than kinesin.

a <html><iframe width="440" height="330" src="http://www.youtube.com/embed/7pBw4FWEt3I" frameborder="0" allowfullscreen></iframe></html>	b <html><iframe width="440" height="330" src="http://www.youtube.com/embed/R4RsXKiknIs" frameborder="0" allowfullscreen></iframe></html>
Movie. 2.1.1 Analyses of the speed of platinum in solution of H₂O₂. (a) Platinum movement in solution of H₂O₂ (b) Analyses of the speed of plutinum by High-speed camera

Fig. 2.1.2 The mean square displacement of a platinum particle.

2.2. Numerical estimation of the speed of the Biomolecular Rocket

<html><body>The numerical simulation revealed that the Biomolecular Rocket can move ten times faster than kinesin.</body></html>

>>see more simulation models

The simulation also demonstrated that the Biomolecular Rocket with many platinum catalysts on the body can move twice faster than a microbead with a hemispherical platinum surface moves because of the difference in the catalytic surface areas between them (Fig. 2.2).

Figure 2.2 shows instantaneous speed at each time steps of kinesin motor, 10 μm beads with a hemispherical platinum surface (catalytic motor without DNA), and 10 μm of the Biomolecular Rocket. We take the average of 100 time step's instantaneous speed of each molecular motor　and make a comparison among them.

As a result, the average speed of the Biomolecular Rocket is calculated as 11.2 μm/s, and the average speed of catalytic motor without DNA is 6.8 μm/s. We assumed that Kinesin moves straightforward at 1.0 μm/s all the time, Kinesin's average speed is calculated as 1.0 μm/s.

Therefore, we estimate that the Biomolecular Rocket moves faster than kinesin. Moreover, the Biomolecular Rocket can get more speed by surface enlargement of catalyst with DNA.

Fig. 2.2 Image of each molecular motor’s instantaneous speed with time

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3. Introduction of a photo-switchable DNA system for the directional control

<html><body>We developed a photo-switchable DNA system for the directional control with a photoresponsive DNA.</body></html>

The photo-switchable DNA system consists of an azobenzene-based photoresponsive DNA. The structure of the photoresponsive DNA is changed by UV light irradiation, then the photoresponsive DNA duplex is dissociated into DNA single strands. By the dissociation of DNA, catalytic engines are dissociated from the body of Biomolecular Rocket. As a result, the directional change of the force generated by O₂ bubble is caused, and the direction of the Biomolecular Rocket is changed. Here, we developed and investigated the photo-switchable DNA system by the following experiments and simulations.

<li>Design of a photo-switchable DNA system for the directional control <li>Investigation of the dissociation rate of the photo-switchable DNA duplex by UV light irradiation experiments <li>Investigation of the directional control of Biomolecular Rocket with the photo-switchable DNA system by numerical simulations </ol></body></html>

3.1. Design of photoresponsive DNA

<html><body>We designed photoresponsive DNA strands for a photo-switchable DNA system to achieve the directional control of Biomolecular Rocket.</body></html>

>>see more methods

We designed a photoresponsive DNA strand based on DNA sequence S^*; four azobenzene molecules were introduced into S^*. Figure 3.1.1 shows that absorbance spectra of DNA strands (A) photoresponsive DNA sequence S^*, (B) DNA sequence S, and (A+B) the duplex of them at a room temperature. The absorbance of (A+B) around 260nm was less than those of (A) and (B). This indicated that the hybridization of (A) with (B) was stable at a room temperature.

Fig.3.1 Absorbance spectra of DNA strands (A) photoresponsive DNA sequence S*, (B) DNA sequence S, and (A+B) the duplex of them at a room temperature.

3.2. Achievement of the photo-switchable DNA system

<html><body>We have succeeded in development of a photo-switchable DNA system.</body></html>
>>see more methods

We introduced the photo-switching DNA system into Biomolecular Rocket in order to control its moving direction.

To investigate the relationship between the strength of UV light and the irradiation time for dissociation of the photoresponsive DNA and determine the valid time for UV light irradiation, we examined two types of strength of UV light.

Figure 3.2.1a represents the absorbance spectra in the condition of UV-light irradiation with the strength of 30 mW/cm². The absorbance of the DNA duplex (A+B) at the wavelength of 260 nm gradually increased from 0 minutes to 5 minutes (Fig. 3.2.1b). This result means that the DNA duplex (A+B) was dissociated after 5 minutes irradiation of UV light. Moreover, the absorbance of the DNA duplex (A+B) at 330 nm decreased from 0 minutes to 5 minutes (Fig. 3.2.1b). This means that the trans-formed azobenzene changed its form to cis-formation. Therefore, we conclude that the dissociation of the photoresponsive DNA can be achieved by 5 minutes irradiation of UV-light (30 mW/cm²).

a	b
Fig. 3.2.1. (a) Absorbance spectra of photoresponsive DNA duplex (A+B) in condition of UV light irradiation (30 mW/cm²). (b) Time course of the absorbance change during UV light irradiation.

Similarly, we studied the dissociation rate of photoresponsive DNA under the condition of UV light irradiation with the strength of 180 mW/cm² (Fig. 3.2.2a). Figure 3.2.2b represents that the DNA duplex (A+B) was gradually dissociated from 0 seconds to 50 seconds because the maximum absorbance at 260 nm increased. Figure 3.2.2c shows that the trans-formed azobenzene changed to the cis-fomed one by the UV irradiation because the absorbance at 330 nm decreased from 0 seconds to 50 seconds. Figure 3.2.2d shows that the cis-formed azobenzene increased because the absorbance at 480 nm increased from 0 seconds to 50 seconds. In summary, the photo-switchable DNA system worked by 50-second irradiation of UV-light (180 mW/cm²). From these results, we conclude that the dissociation of photoresponsive DNA by UV-light irradiation was achived.

a	b
c	d
Fig. 3.2.2 Spectrum analysis of photoresponsive DNA duplex(A+B) in condition of UV-light(180 mW/cm²) irradiation

3.3. Directional control of the Biomolecular Rocket by the photo-switchable DNA system

<html><body>By numerical simulations, we found that the Biomolecular Rocket changes its direction by the UV light irradiation even though the Biomolecular Rocket is affected by the viscous resistance force and Brownian dynamics of water.</body></html>

>>see more Simulation Models

Figure 3.3 shows the trajectories of the the Biomolecular Rockets of 10 μm in diameter by the numerical simulation. Each trajectory shows the movement of the Biomolecular Rocket that detaches catalytic engines after the irradiation of UV light when 10 seconds, 15 seconds, 20 seconds, and 25 seconds passed. This simulation results suggested that the Biomolecular Rocket can change its direction immediately after all catalytic engines are dissociated even though the viscous resistance and Brownian movement prevented the controlled movement of the Biomolecular Rocket. From these results, we conclude that the Biomolecular Rocket changes its direction by UV light irradiation.

Fig. 3.3 Trajectories of Biomolecular Rockets of 10 μm in diameter by the numerical simulation. Each trajectory shows the movement of Biomolecular Rocket that detaches catalytic engines after the irradiation of UV light when 10 seconds, 15 seconds, 20 seconds, and 25 seconds passed.

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 |}
 :&nbsp;&nbsp;&nbsp;&nbsp;Figure 0.1a, b and c are microscope images of 40 μm microbeads. Figure 0.1a shows microbeads before vapor deposition of metals. Figure 0.1b shows microbeads after vapor deposition of Au (gold) on the microbeads. Figure 0.1c shows microbeads after additional vapor deposition of Cr (chromium) on the Au-deposited microbeads. The microbeads had three types of surface areas because the angular alignment of the beads was changed when Cr was deposited on the Au-deposited microbeads.
-:&nbsp;&nbsp;&nbsp;&nbsp;Similarly, Figure 0.1e, f and g are microscope images of 10 μm microbeads. Figure 0.1e shows microbeads before vapor deposition of metals. Figure 0.1f shows microbeads after vapor deposition of Au on the microbeads. Figure 0.1g shows microbeads after additional vapor deposition of Cr on the Au-deposited microbeads. The 10 μm microbeads probably had three types of surface areas. From these results, we conclude that selective coating of microbeads for Biomolecular Rocket was achieved.
+:&nbsp;&nbsp;&nbsp;&nbsp;Similarly, Figure 0.1e, f and g are microscope images of 10 μm microbeads. Figure 0.1e shows microbeads before vapor deposition of metals. Figure 0.1f shows microbeads after vapor deposition of Au on the microbeads. Figure 0.1g shows microbeads after additional vapor deposition of Cr on the Au-deposited microbeads. The 10 μm microbeads probably had three types of surface areas. From these results, we conclude that selective coating of microbeads for the Biomolecular Rocket was achieved.
 {|style="margin-left:30px" width="930px"position:fixed;z-index:-9999;top:0;left:0;min-width:100%;min-height:100%"" border="1"
 |&nbsp;&nbsp;<html><body><nobr>40 μm silica beads</nobr></body></html>

Biomod/2012/Titech/Nano-Jugglers/Results: Difference between revisions

Revision as of 23:57, 27 October 2012

Results

0. Construction of Biomolecular Rocket

0.1. Selective coating of the body

0.2. Design of linker DNA strands

0.3. Selective DNA conjugation to the microbead body of Biomolecular Rocket

0.3.1. Selective conjugation of DNA to polystyrene surface area

0.3.2. Selective conjugation of DNA to metal surface area

0.4. Catalyst attachment with DNA hybridization

<html><body><font color="red">1. Power supply for the rail-free movement of the Biomolecular Rocket</font></body></html>

1.1. Power supply for rail-free movement by using catalase catalytic engine

1.2. Power supply for rail-free movement by using platinum catalytic engine

1.3. DNA hybridization in solution of H₂O₂

2. Realization of the high-speed movement of the Biomolecular Rocket

2.1. Power supply for the high-speed movement with platinum catalytic engines

2.2. Numerical estimation of the speed of the Biomolecular Rocket

3. Introduction of a photo-switchable DNA system for the directional control

3.1. Design of photoresponsive DNA

3.2. Achievement of the photo-switchable DNA system

3.3. Directional control of the Biomolecular Rocket by the photo-switchable DNA system

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Biomod/2012/Titech/Nano-Jugglers/Results: Difference between revisions

Revision as of 23:57, 27 October 2012

Results

0. Construction of Biomolecular Rocket

0.1. Selective coating of the body

0.2. Design of linker DNA strands

0.3. Selective DNA conjugation to the microbead body of Biomolecular Rocket

0.3.1. Selective conjugation of DNA to polystyrene surface area

0.3.2. Selective conjugation of DNA to metal surface area

0.4. Catalyst attachment with DNA hybridization

<html><body><font color="red">1. Power supply for the rail-free movement of the Biomolecular Rocket</font></body></html>

1.1. Power supply for rail-free movement by using catalase catalytic engine

1.2. Power supply for rail-free movement by using platinum catalytic engine

1.3. DNA hybridization in solution of H2O2

2. Realization of the high-speed movement of the Biomolecular Rocket

2.1. Power supply for the high-speed movement with platinum catalytic engines

2.2. Numerical estimation of the speed of the Biomolecular Rocket

3. Introduction of a photo-switchable DNA system for the directional control

3.1. Design of photoresponsive DNA

3.2. Achievement of the photo-switchable DNA system

3.3. Directional control of the Biomolecular Rocket by the photo-switchable DNA system

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1.3. DNA hybridization in solution of H₂O₂