Biomedical Engineering Reference
In-Depth Information
principle. by. monitoring. the. peak. positions. of. the. ODMR. spectra. and. resolving. the.
rotational. motion. of. FNDs. in. a. live. cell. in. millisecond. timescales. (McGuinness. et. al..
2011)..They.apply.a.uniform.magnetic.ield.to.the.FND-labeled.HeLa.cells.to.produce.an.
orientation-dependent. Zeeman. shift. on. the. higher. levels. of. the. ground. state. in. a. single.
(N-V)
−
.center.and.determine.the.orientation.of.the.(N-V)
−
.quantization.axis.with.respect.
to.the.external.magnetic.ield.from.the.ODMR.peak.positions.(Figure.25.11)..The.rotational.
motion. of. the. (N-V)
−
. center. is. continuously. monitored. over. 16.h,. with. the. position. and.
orientation.plotted.in.four.dimensions..The.restricted.translational.motion.is.in.agreement.
with. previous. studies. on. the. internalization. of. similar. FNDs. in. the. same. cell. types.
½ ∆ω(θ)
2
1.9
t
= 0 h
θ = 55±1°
1.8
Zero crystal field splitting 'D'
60
55
50
45
40
35
1
0.9
NV
axis
0.8
t
= 16 h
θ
2.8 s-408 pts
89 ms-13 pts
B
0
θ = 57±1°
0.7
2.75
30
2.8
2.85
MW frequency (GHz)
2.9
2.95
3
0
2
4
6
8
Time (h)
10
12
14
16
(a)
(b)
NV
axis
θ = 54±1°
400
56°
t
= 2 h
B
0
300
θ
200
46°
θ = 46±1°
t
= 5 h
100
0
0
100
50
200
100
300
(c)
150
400
Figure 25.11
(See companion CD for color insert.)
.Orientation.tracking.for.the.N-V.axis.of.a.single.FND.in.a.HeLa.cell..(a).
Changes. in. the. orientation. of. the. N-V. quantization. axis. relative. to. the. external. magnetic. ield. owing. to. the.
ND.motion..The.changes.are.manifest.in.the.orientation-dependent.Zeeman.splitting.observed.in.the.ODMR.
spectrum.shown.at.various.times.over.the.HeLa.cell.lifetime..(b).Measured.orientation.of.the.ND.as.a.function.
of.time..(c).Four-dimensional.tracking.(position.and.orientation).for.the.N-V.axis.of.a.single.FND.in.a.HeLa.cell.
over.a.3.h.period..(Reprinted.with.permission.from.Macmillan.Publishers.Ltd.,.
Nat. Nanotechnol
.,.Mcguinness,.
L.P.,.Yan,.Y.,.Stacey,.A.,.Simpson,.D.A.,.Hall,.L.T.,.Maclaurin,.D.,.Prawer,.S.,.Mulvaney,.P.,.Wrachtrup,.J.,.Caruso,.
F.,. Scholten,. R.E.,. and. Hollenberg,. L.. C.L.,. Quantum. measurement. and. orientation. tracking. of. luorescent.
nanodiamonds.inside.living.cells,.6,.358-363..Copyright.2011.)
