manipulating life with intense magnetic fieldsbone loss is a problem for astronauts hammer et al.,...

Probing and Manipulating Soft

Matter with Intense Magnetic Fields

• Soft Matter

• Recent Work

• Future directions

Cell 5 NHMFL:

Bmax = 31 Tesla BB’max = 5100 T2/m

Soft Matter in Magnetic Fields, Valles 1

Soft Matter

• kT matters to

mechanical properties

• Dynamic systems

• Polymers

• Colloids

• Bio-polymers

• Cells

• Organisms


Bio-diamagnetism

B

Magnetic response of covalent bonds

M

M = B

-10-7 to -10-6

for nearly all organics


M = B M = B

B

Diamagnetic Anisotropy - Torque

Energy

Torque


Aligning Bio-targets using B

Cannot align a single molecule:

U=(U||- U ) << kBT

@ 20 Tesla

Can align bio-molecular assemblies

Retinal rods, Microtubules, DNA,

RNA, Membranes, Fibrin, Viruses

Can align molecules with steric interactions


6

A Molecular Assembly: Microtubule

Microtubule growing

(-) end

(+) end

1. Tubulin dimers + heat = microtubules

2. Microtubules are birefringent

3. Microtubules ubiquitous

dimers

microtubules

Mitotic apparatus

Bundles of MTs in frog egg (from Development)

Soft Matter in Magnetic Fields, Valles

Birefringence induced by alignment Wim Bras (1998)

Solution of polymerizing microtubules exposed to magnetic field – viewed through crossed polarizers

B


Soft Matter in Magnetic Fields, Valles *W. Bras (1998)

=> Can align a single microtubule!

Diamagnetic Anisotropy of a Microtubule

U = (U - U||) ≈ 10 kBT

20 Tesla

8

Potential Targets for B

Targets must satisfy:

B 2V > 10 kBT

For, 10-8

and B = 10 T

Must have:

V > (1.3 m)3

www.animalport.com


Aggregation of Organic Molecules

aggregates

J. C.Gielen et al. Langmuir 2009, 25, 1272-1276

Nijmegen, Grenoble and Durham groups

Sexithiophene

Size


Aggregation of Organic Molecules

aggregates

J. C.Gielen et al. Langmuir 2009, 25, 1272-1276

Nijmegen, Grenoble and Durham groups

Sexithiophene

Aggregate structure from Xray and birefringence


Orienting Mesochannels

eration of perpendicular recording media of beyond

1 Tbit inch 2. Moreover, the fine control of pore size is im-

portant for the design of highly sensitive chemical sensors

and the separation of molecules that are too large to be

treated with crystalline zeolite molecular sieves with micro-

pores.

Recently, a superconducting magnet with a high magnetic

field (> 10 T) was developed for various applications.[10] One

of the most convenient and versatile methods for the orien-

tation of materials is the application of a high magnetic

field; this is effective even for paramagnetic or diamagnetic

materials with extremely small magnetic susceptibilit y.[11] I t

has been shown that, when a high magnetic field is applied,

the rodlike macromolecules formed through the self-assem-

bly of surfactants are uniaxially oriented due to the magnet-

ic anisotropies of the constituent surfactant molecules.[12]

Tolbert et al. reported a macroscopic orientation of unpoly-

merized silicate-sur factant liquid crystals under a high mag-

netic field of 11.7 T.[12b] They then succeeded in preparing

mesoporous silica monoliths with macroscopic orientation of

the mesochannels through polymerization of silica spe-

cies.[12b] However, their system is limited to the production

of monolithic materials, and a rather different strategy is re-

quired for the preparation of mesoporous films. Recently,

we reported the partial perpendicular alignment of meso-

channels in mesoporous silica films, which was achieved by

combining the evaporation-induced self-assembly (EISA )

method and magnetic processing at 12 T.[13] Ogura, Okubo,

and co-workers and Ozeki et al. also reported the magneti-

cally induced orientation of mesochannels in films.[14] The

magnetic effect reported previously by us was limited to

only high-molecular-weight surfactants such as block copoly-

mers and was not applicable to low-molecular-weight surfac-

tants (e.g., cationic surfactants and nonionic surfactants such

as the Brij series), because rodlike self-assemblies composed

of low-molecular-weight surfactants cannot provide suffi-

cient difference in magnetic energy due to anisotropy (DE)

for smooth magnetic orientation. Therefore, the develop-

ment of a process applicable to many types of surfactants of

various lengths is an emerging topic.

We demonstrate herein the magnetical ly induced orienta-

tion of mesochannels in mesoporous silica films prepared

with low-molecular-weight surfactants under an extremely

high magnetic field of 30 T (Figure 1). This process is princi-

pally applicable to any type of surfactant with magnetic ani-

sotropy because the extremely high magnetic field can pro-

vide sufficient DE for smooth magnetic orientation. The

pore diameter of the oriented mesochannels can therefore

be controlled by using a variety of surfactants. The magneti-

cally induced mesochannels were fully characterized by the

complementary combination of a series of X-ray diffraction

(XRD) measurements together with transmission electron

microscopy (TEM) and high-resolut ion scanning electron

microscopy (HR-SEM) observat ions. This process is effec-

tive in controlling the alignment of mesochannels without

specific modifications of substrate surfaces and/or complex

preparative conditions.

Results and Discussion

Firstly, the magnetic effect of mesoporous silica films pre-

pared from a CTA B-based precursor solution (CTA B = ce-

tyltrimethylammonium bromide) was investigated. The

thicknesses of all the films were about 1 mm because the

same amount of precursor solution was cast onto each sub-

strate. The conventional q–2q scanning XRD profiles of the

A bstract in Japanese:

Figure 1. Schematic view of the experiment al setup for the preparation of mesoporous silica films under the extremely high magnetic field of 30 T

ACHTUNGTRENNUNGgenerated by a hybrid magnet.

1506 www.chemasianj .org 2007 Wiley-VCH Verlag GmbH & Co. KGaA , Weinheim Chem. Asian J. 2007, 2, 1505–1512

FULL PAPERS

Yusuke Yamauchi et al., Chem. Asian J. 2007, 2, 1505 – 1512

Tsukuba Magnet Laboratory


Creating Cornea Material with

Magnetically Aligned Collagen

0 T 7 T Two layers

Collagen fibrils Multi-lamellar

J. Torbet et al., Biomaterials 28 (2007) 4268

Grenoble HMFL


Swimming Paramecium

0 Tesla 30 Tesla


What determines the right angle

geometry?

1

3

2

1

2

Dividing Frog Embryos


Cleavages Reoriented by B

Time (NT) 0 1 2 3

Bz=17 T B

Bz=0 T


22 Tesla 0 Tesla

Aligning the Mitotic Apparatus


Diamagnetic Forces and Levitation

Magnetic Force

fB = - gV = fg

Levitation for:

UB =1

2cB2V

fB = -cBdB

dzV


Magnetic Levitation:

Simulation of Low Gravity

• Biological things: Protein crystals, yeast, bacteria, mammalian cells, mice, frogs

• Fluids: helium, spinning drops, phase changes

• Granular matter Magnetically

levitated water

droplet


Magnetic Levitation

• Levitation requires

• Reduces stresses

• Levitation can be stable Levitated Frog Embryos

BdB

dz»1400 T2 /m


Magnetic Levitation of MC3T3 Osteoblast Cells a low gravity simulation experiment

Bone loss is a problem

for astronauts

Hammer et al., Microgravity Sci. Technol (2009) 21:311–318

• Levitate “bone”cells for 2 days

• Check gene expression


Paramecium - a gravity senser

v = 500 μm/s

Reynold’s number ≈ 0.1

200 μm

ρP = 1.04 ρwater

Sediments, S ≈ 100 μm/s


Magnetic Force Buoyancy Variation


* Ikezoe, Hirota, Nakagawa and Kitazawa, Nature (1998)

K. Guevorkian and JM Valles, Jr., Appl. Phys. Lett. (2004)

Apparent Weight

23

Paramecia in Variable g

5g -5g

Paramecium Caudatum in Gd-DTPA doped solution with apparent weight multiplied by 5 (left) and -5 (right).


Swimming in -6 to 6 g

earth

active

regulation


Future Research

• manipulation of living matter

• materials science, e.g. directing self assembly of large molecules

• effects of magnetic fields on biological systems

• Animal system MRI at 17 T!

cleavages, normally horizontal, were vertical (i.e., parallel withthe magnetic field). Moreover, the number of normal hori-zontal cleavages decreased with the increasing strength of themagnetic field. To quantitate this effect, we scored eachindividual third cleavage among the eight cells of a fixedembryo as horizontal or vertical. Fig. 2 shows top and sideviewsof embryoswith four (Fig. 2 a and b), three (Fig. 2 c andd), two (Fig. 2 e and f ), one (Fig. 2 g and h), or zero (Fig. 2 iand j) horizontal third cleavages. Most oblique cleavagescreated a cell whose body spanned the AV tiers as in Fig. 2dand were scored asvertical. The average number of horizontalthird cleavages per embryo are graphed as a function ofmagnetic-field strength (Fig. 2k). With increasing fieldstrength, the average number of normal horizontal thirdcleavages per embryo decreases from the control-embr yovalue of 2.7 to 0; in short, virtually all third cleavages arevertical at 16.7 T. The percentage of embryos that developedto normal tadpoles (50%) was independent of the number ofvertical third cleavages per embryo and did not vary over therange of 1.7–16.7 T. The remainder exhibited field-inducedgastrulation defects (J.M.D., J.M.V., Jr., K.L., and K.L.M.,unpublished work).

Next, the magnetic field was applied perpendicularly to theAV axis of the egg (AV-perpendicular) to determine whetherthe first or second cleavage could be reoriented in an analo-gous fashion. Eggs were positioned in a homogeneous 15-TAV-perpendicular field of a horizontal-bore solenoid. Sampleswere withdrawn at the end of the first, second, and thirdcleavage. No alteration was obser ved for the first-cleavageorientation. The second cleavage, however, was reoriented ina significant number of cases (17–24%). Fig. 3 illustrates thetwo classes of reorientation that were noted. In the first class,the second cleavagesare still vertical but are not orthogonal tothe first-cleavage plane. Rather, they are at oblique angles,resulting in two large and two small blastomeres (Fig. 3a). In

the second class, one of the two second cleavages is reorientedto a horizontal plane, parallel to the magnetic field, resultingin a small animal-hemisphere blastomere on top of a largevegetal blastomere and a normal-looking half embryo (Fig.3b). For comparison, a control four-cell embryo is also shown(Fig. 3c). AV-perpendicular fields did not affect third cleav-ages. A ll embryos from the AV-perpendicular field developednormally.

DISCUSSION

Our results indicate that cleavage furrows align parallel to astrong magnetic field. This parallel alignment leads to thecomplete reorientation, from horizontal to vertical, of thethird cleavage in an AV-parallel 16.7-T field without affectingthe first and second cleavages. No effect is expected on firstand second cleavage, because their planesare already orientedparallel to the applied field. By contrast, in an AV-perpendicular field, only the planes of the first and secondcleavages are expected to be turned by the field, becausehorizontal third cleavagesare already parallel to the field. Theabsence of reoriented first cleavages is explained easily, be-cause the first cleavage can orient along anymeridian about theAV axis (17). The finding that reoriented second cleavagesoccurred much less frequently than reoriented third cleavagesin both the controls and in a magnetic field suggests that thecell shape at second cleavage strongly constrains the orienta-tion of the cleavage furrow compared with cell-shape con-straints at third cleavage. This conclusion agrees withBjerknes’ calculations of M A orientation in Xenopus. Hefound that the third-cleavage M A was the most susceptible toreorientation (7). Our data also support this finding, as one offour third cleavages in control embryos is vertical (Fig. 2k).Quantifying thechangesfrom theorthogonal aspect showsthatthere is a notable deviation from standardized descriptions ofthird-cleavage planes in normal Xenopus embryos (1).

FIG. 2. Third cleavage in an AV-parallel magnetic field. Top (a, c, e, g, and i) and side (b, d, f, h, and j) views of eight-cell embryos from anAV-parallel field, showing the classes of third cleavage reorientation. For the side views, the embryo in the top view was rotated with the animalpole away from the viewer. The numbers of horizontal cleavages depicted are four (normal; a and b), three (c and d), two (e and f ), one (g andh), and zero (i and j). (k) The average number of horizontal third cleavages per embryo as a function of field strength.

FIG. 1. Schematic diagrams of embryos in AV-parallel and AV-perpendicular magnetic fields. g is the gravity vector, and B is themagnetic-field vector.

FIG. 3. Views of embryos from an AV-perpendicular field, show-ing the classes of second-cleavage reorientation. (a) The secondcleavage is oblique to the first. (b) A single second cleavage ishorizontal. (c) The second cleavage is normal.

14730 Cell Biology: Denegre et al. Proc. Natl. Acad. Sci. USA 95 (1998)


Themes

• Nano to micro science

• Interdisciplinary

– Materials science, Chemistry, Biology, Physics

• International

– Japan, UK, China, The Netherlands, France

• Small fraction of facility use


Infrastructure Suggestions I

• in situ probe development – optical microscopy

– xray scattering

• Create resistive magnet inserts – temperature controlled

– gas control


Infrastructure Suggestions II

• Add superconducting

solenoids with room

temperature bores

– initial tests

– long term experimentation

• Interdisciplinary work needs

local soft matter expertise


• Niche field – times that magnetic field

effects helpful and times not

• Suggestions

– Create better temperature control

– Develop optical tools

– Make some continuous fields available for tests, long term levitation


Manipulating Life with Intense Static

Magnetic Fields

• Getting started

• Magnetic properties of

biomaterials

• Aligning Living Entities

• Free levitation

• Magneto-Archimedes levitation

• What to take away


soft matter experiments, i.e. molecular organic matter, polymers, aggregates,

and biological materials where in high magnetic fields the diamagnetic energies

and forces become comparable with thermal energies and gravity.

current high magnetic field soft matter experiments, what scientific questions

these experiments address, what scientific advances they may lead to, and/or

what challenges they may face (considering that often different disciplines as

physics are involved).

likely future directions for high magnetic field soft matter experiments

what types of facilities would be most useful our committee.


Intense Magnetic Fields

Cell 5 NHMFL: Bmax = 31 Tesla BB’max = 5100

T2/m


Experimental Facilities

• In situ

microscopy

• Thermostats

• Long term

levitation using

superconducting

solenoids

• Xray scattering


Manipulating Microtubule Structure Formation

Jay X. Tang, Yongxing Guo, Yifeng Liu

http://www.probes.com/

25 nm

10 mm


Magnetism of Earth’s Materials

diamagnetic 98%

repelled by magnets

water, protein

Magnetically

levitated water

droplet

ferro or para magnetic 2%

attracted to magnets:

Fe, O2

frog egg paramecium Soft Matter in Magnetic Fields, Valles 37


microtubules

Mitotic apparatus

Bundles of MTs in frog egg (from Development)

Bio structures with microtubules

38

Flipping Apparent Weight at

Surface

2g

-2g U turns at

surface

Dwells at surface

Paramecium tetraurelia in Gd-DTPA

solution

surface

surface


22 Tesla 0 Tesla

Mitotic Apparatus Orientation


Sensitive Time Surprise

time 0 NT 1 NT 2 NT 3 NT

Bz=17 T

Bz=17 T

a “memory” effect

B


“Centrosome Cycle” Model

In the absence of other effects…

…centrosome motion leads to planes at right angles.


Magnetic Rotation of the Centrosome Cycle

B on B off


Centrosome Cycle Reorientation Model

Agrees with observations – vertical third cleavages

– horizontal second cleavages

– continuous range of MA angles

– bizarre time of sensitivity

2nd cleavages


Diamagnetic Forces and Levitation

Magnetic Force

fB = - gV = fg

Levitation for:

UB =1

2cB2V

fB = -cBdB

dzV


Magnetic Levitation

• Levitation requires

• Reduces stresses

• Levitation can be stable Levitated Frog Embryos

BdB

dz»1400 T2 /m


Motivation: What does gEarth do?

• Provides directional cues

– e. g. plants grow up

• Affects biological

structure

– e.g. strengthens muscles

• Does it work at the

cellular or molecular

level?

Going up…

47 Soft Matter in Magnetic Fields, Valles

Paramecium - a gravity senser

v = 500 μm/s

Reynold’s number ≈ 0.1

200 μm

ρP = 1.04 ρwater

Sediments, S ≈ 100 μm/s


Paramecium - a gravity senser Negative

gravitaxis Negative gravi-

kinesis

v = P( ) + S

v

P S

gP(0) > P(π)

or upward swimmers push harder


Paramecium - a gravity senser Negative

gravitaxis Negative gravi-

kinesis

v = P( ) + S

v

P S

gP(0) > P(π)

or upward swimmers push harder

Remarkable: Apparent weight ≤ 100

pN! Effects disappear for neutral

buoyancy! Are these active or passive responses?


Magnetic Force Buoyancy

Variation


* Ikezoe, Hirota, Nakagawa and Kitazawa, Nature (1998)

K. Guevorkian and JM Valles, Jr., Appl. Phys. Lett. (2004) 51

Effective Apparent Weight

•Measured in “g”

•vary χs (Gd-DTPA) Resistive magnet

(B dB/dz)max= 5100 T2-m-1 NHMFL


Karine Guevorkian

Paramecia in FOV


Paramecia in Variable g

5g -5g

Paramecium Caudatum in Gd-DTPA doped solution with apparent weight multiplied by 5 (left) and -5 (right).


Flipping Apparent Weight at

Surface

2g

-2g U turns at

surface

Dwells at surface

Paramecium tetraurelia in Gd-DTPA

solution

surface

surface

Is this negative

gravitaxis? Soft Matter in Magnetic Fields, Valles 55

Fraction at Surface

surface

Paramecium tetraurelia in Gd-DTPA solution Soft Matter in Magnetic Fields, Valles 56

Surface Swimming

Canted swimmers

Left handed circles


Mechanical Model: Forces

w

P

D

N

B

Propulsion Drag

weight (apparent)

Normal


Mechanical Model: Torques

w

P

D

N

B

Magnetic

Drag (rotation)

Normal force


Mechanical Model: Critical Angle

B c


Mechanical Model: Critical Angle

sinc

e

then

Predicts: accumulated swim

canted Predicts: easier to turn against

w

A Passive Response Model


Linear Gravi-kinetic Response “A

ctiv

e” r

esp

on

se

Effective apparent weight (g)

Swimmers fight the

force

Symmetry implies that

magnetic force exerts

same influence as

gravity


Summary of Paramecia Expts

Magnetic Force Buoyancy Variation

Passive accumulation at upper

surfaces

Gravi-kinesis may be an active

response Soft Matter in Magnetic Fields, Valles 63

To Take Away

Intense Magnetic Fields:

– can align biological structures as small as (1 m)3

– can levitate living material (14 T2/cm)

– can illicit biological responses

– can be a tool for cell biology!


Speed Distributions


Linear Response

v = αfgm + β

Up/down asymmetric


Stalling at 10g

Maximum propulsion force:

0.7 nN


B = 9 Tesla


Time dependence of pattern birefringence image

Mechanical instability of aligned, growing

microtubules


Swimming for Re << 1

g

Decompose velocity

Sedimentation, S g

Propulsion, P


Propulsion depends on angle!

Gebauer M, Watzke D, Machemer H, NATURWISSENSCHAFTEN 86, 352-356 (1991).

P(

) - P

(90˚)

evidence of gravitational sensitivity...

v = P( ) + S

v

P S

g


Force Response

Baba SA, Mogami Y, Otsu T (1999)

Scales with “g” (centrifugation)

P(

) - P

(90˚)

“g” 1g 5g


Magneto-Archimedes Levitation

Continuous buoyancy variation

• Strong inhomogeneous B

• Magnetic “background” fluid

A. T. Catherall, L. Eaves, P. J. King and S. R. Booth, Nature 422,

579(10 April 2003)

“Floating Gold” in cryogenic oxygen

B


Dividing Frog Embryos


manipulating life with intense magnetic fieldsbone loss is a problem for astronauts hammer et al.,...

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