Molekulare Maschinen und Nanomechanik

Seminarvortrag zu nanostrukturierte Festkörper

Christian KrambergerInstitut für Materialphysik Universität Wien

Outline

Definition

Proposed Devices

Interlocked Molecules

Bio-Molecules

Light induced Rotation

What is a molecular machine ?

„Speaking of molecular machines isn't a metaphor. If something has moving parts and does useful work, we call it a machine. If something is nanometers in scale and has a precise arrangement of bonded atoms, we call it a molecule, or a molecular assembly. If something matches both these descriptions, we can properly call it a molecular machine; if it comprises many parts, each worthy of the name 'machine', it may be better described as molecular machine system.“

(K. Eric Drexler Trends in Biotechnology, January 1999, Vol 17 No 1, pp 5-7)

Definition

Visions of Nanomechanics

These machines consist of several thousand atoms. They are pure fiction and are pretty far beyond the current state of nanotechnology.

Bearing

Planetary Gear

Differential Gear

http://www.imm.org

Some more Proposals

Interlocking joint of C structures terminated with O and N

A Neon selective molecular pump

A fine motion controller for molecular assembly

http://www.imm.org

Nanotube GearsMD with Brenner potentialsBonds are stable up to 3000 KSlipping above 600 KSynthesis is a „future task“

(14,0) (14,0) (10,0) (18,0)

working

slipping

http://people.nas.nasa.gov/~globus/papers/MGMS_EC1/simulation/paper.html

Nanotube Shaft and Gear

(14,0) (14,0)

A different orientation of the Benzene teeth yields a linear motor.

http://people.nas.nasa.gov/~globus/papers/MGMS_EC1/simulation/paper.html

How to Drive a NT Gear

Place two elementary charges at opposite sites and apply a very high frequency electrical field (laser). The resonance frequency of this system is 140 GHz.If the laser frequency is not close to it, the NT is either switching between clockwise and counter clockwise rotation, or is just oscillating and does not rotate at all.

(14,0)

http://people.nas.nasa.gov/~deepak/papers/motor/paper.html

Driving at 140 GHz

One individual NT driven NTgets due to thermal fluctuations out of phase, even at its resonance frequency.

A dissipative Gear system runs stable once it has started, even with a randomly pulsed Laser as long as the system does not stop rotating.

http://people.nas.nasa.gov/~deepak/papers/motor/paper.html

Molecular Switch Tunnel Junction

Tetrathifullfalene TTF

Dioxynaphthalene DNP

5000 molecules per 0.007 m2

junction.State d decay time 10-15 min.Devices are switched at+/- 2 V and read with 0.1 V.Electrical breakdown at 3.5 V.Area of 140 A2 allows rotaxanes to act individually.

a b c d

- -

+ +

dumpbell

tetracationc Cyclophane

CHEMPHYSCHEM 2002, 3, 519-525

Junction Characteristics

black line: 0.007 m2 junction with approximately 5000 moleculesred line : control junction with pure dumpbells (no rings)

Hysteresis of an individual junction.

Switching and reading a bit for 35 cycles.

CHEMPHYSCHEM 2002, 3, 519-525

Biological Molecular Machines

Nature provides a wide spectrum of transport molecules.We will focus on conventional Kinesin from bovine brains.

Structure of Kinesin

nature Vol. 389 p561-567 (1997)

Kinesin Transport

Motor-Proteins move along cytoskeletal filaments driven by ATP. Kinesin is one of them and moves along cellular microtubuli.

In laboratory the transport mechanism is run under reversed conditions. Layers of Kinesin can move randomly orientated microtubuli forward with 800 nms-1.

http://faculty.washington.edu/hhess/index_files/slide0001.htm

Directed Motion3 gl-1

0.5 gl-1 18gl-1

At a medium concentration of Kinesin attached to a share-deposited PTFE Film. Parallel tracks of Kinesin lead to directed motion. Scale bares are 10 m. Microtubuli are sampled every 5 s colored from red to violet.

medium concentration

high concentration

nanotechnology 10 (1999) 232-236

Control of Motion

Motion is powered by ATP. So the issue is controlling the concentration of ATP.Caged ATP can be released by irradiationwith UV light. An ATP consuming enzyme then quickly depletes the free ATP storage. single step 4-6 mATP lasts for 105 cycles(without Hexokinase)

nano letters 2001 vol. 1, no. 5, 235-239

Transporting Cargo

The interaction between Kinease and microtubuli is restricted to their contact sides. The free sides of the microtubuli can be used to bind (load) cargo. This has been demonstrated with Streptadavin coated polystyrene particles.

Microtubule giving a particle a lift.

nano letters 2001 vol. 1, no. 5, 235-239

Motor Type I

Above 60 °C and irradiation with > 280nm the left and right identical parts rotate continuously around the central C=C bond.a

b

d c

(3R,3´R)-(P,P)-trans-1,1´,2,2´,3,3´,4,4´,-octahydro,3,3´,dimethyl-4,4`,biphenantrylidene

proc nat acad sci usa Vol 99, Iss8, pp4945-4949

Motor Type I in E7-LC FilmA LC film was doped with (6%) 6a and then irradiated with > 280 nm at RT. The 6a turned into 6d and increased spacing between the E7 (LC) molecules.After heating the activated thickened film the motor cycle was completed.Thus the motor works in an LC environment.

0s 10s 20s 30s 40s 80s proc nat acad sci usa Vol 99, Iss8, pp4945-4949

Sketch of the effect on E7-LC

6a6b6dLC

proc nat acad sci usa Vol 99, Iss8, pp4945-4949

Motor Type II

Type II has a distinct lower and upper part. The lower part can be attached to other molecules or surfaces.

a b

d c

Napthothiopyran

Thioxanthene

j am chem soc Vol 124, Iss 18, pp5037-5051

Rotation of Motor Type II

d a

The upper part rotates counter clock wise to the lower one.

Placing different atoms or groups at the sites X and Y affects the energy barrier for the thermal induced isomer transition. Thus the speed of rotation becomes tunable.

j am chem soc Vol 124, Iss 18, pp5037-5051

The End

Congratulations you have just survived my talk. Thanks to anyone that is still awake and reads this

and shame on anyone else!

Literature 

A DNA fuelled molecular machine made of DNABernard Yurke, Andrew J. Turberfield, Allen P. Mills Jr., Friedrich C. Simmel, Jennifer L. Neumann nature vol 406 p605-p608 10.08.2002Molecular motors: structural adaptions to cellular functionsJoe Howardnature vol 389 p561-p567 09.10.1997Light-Controlled Molecular Shuttels Made from Motor Proteins Carrying Cargo on Engineered SurfacesHenry Hess, John Clemmens, Dong Quin, Jonathan Howard, Viola Vogelnano letters 2001 vol. 1, no. 5 235-239 21.02.2001Molecular shuttels: directed motion of microtubulus along nanoscale kinesin tracksJohn R Dennis, Jonathan Howard, Viola Vogelnanotechnology 10 (1999) 232-236 01.09.1998Molecular Shuttels based on Motor ProteinsHenry Hess, John Clemmon, Robert Doot, Johnathon Howard, Viola VogelNinth Foresight Conference on Molecular NanotechnologyLight-driven molecular switches and motorsFeringa BL, Kommura N, Van Delden RA, Ter Wiel MKJappl phys a mat sci progress Vol 75, Iss 2, pp 301-308Second generation light-driven molecular motors. unidierectional motion controlled by a single stereogenic center with near perfectphotoequlibria and acceleration of the speed of rotation by structural modificationKoumura N, Geertsema EM, van Gelder MB, Meetsma A, Feringa BLj am chem soc Vol 124, Iss 18, pp5037-5051Unidirectional rotary motion in a liquid enviroment: Color tuning by a molecular motorvan Delden RA, Koumura N, Harada N, Feringa BLproc nat acad sci usa Vol 99, Iss8, pp4945-4949Building Molecular Machine SystemsK. Eric DrexlerTrends in Biotechnology, January 1999, Vol 17 No 1, pp 5-7.A Phenomenological Model of the Rotation Dynamics of Carbon Nanotube Gears with Laser Electric FieldsDeepak Srivastavahttp://people.nas.nasa.gov/~deepak/papers/motor/paper.htmlTwo-Dimensional Molecular Electronics CircuitsYi Luo, C. Patrick Collier, Jan O. Jeppeson, Kent A. Nielson, Erica Delenno, Greg Ho, Julie Perkins, Hsian-Rong Tseng, Tohru Yamamoto, J, Fraser Stoddart, and James R. HeathCHEMPHYSCHEM 2002, 3, 519-525Institute of Molecular Manufactoringhttp://www.imm.orgMolecular Dynamics Simulations of Carbon Nanotube Based GearsJie Han and Al Globus, MRJ, Inc., Richard Jaffe, NASA, Glenn Deardorffhttp://people.nas.nasa.gov/~globus/papers/MGMS_EC1/simulation/paper.html