S
1
Supporting Information
Micromotor
-Based Lab
-on
-C
hip Immunoassays
Miguel García
1, 2,‡
,
Jahir Orozco
1,‡
, Maria Guix
1,3,‡
, Wei Gao,
1
Sirilak Sattayasamitsathit,
1
Alberto Escarpa
2
, Arben M
erkoçi
3
and Joseph Wang
1*
1
Department of Nanoengineering, University
of California
-San Diego, La Jolla, CA 92093, USA
2
ICREA & Nanobioelectronics & Biosensors Group, Catalan Institute of Nanotechnology, CIN2
(ICN
-CSIC), Bellaterra, E
-08193 Barcelona, Spain
3
Department of Analytical Chemistry and Chemical Engineering, Un
iversity of Alcalá, E
-28871
Alcalá de Henares, Madrid, Spain.
*E
-mail: josephwang@ucsd.edu
Supporting videos description.
SI Video S1A.
Guided movement of the unmodified polymer/Ni/Pt microengine
within different
sections of a
LOC microchannel network containing a PBS solution along with the H
2
O
2
fuel and
NaCh surfactant.
SI Video S2.
A nti
-IgG
-modified microtransporter capturing multiple S
-PP
-tagged
-IgG.
SI Video S3.
Pick
-up and transport of a s
ingle antigen
-coated
microsphere
by the anti
-IgG
-
modified microtransporter.
SI Video S4.
Negative controls.
SI Video S5.
‘ On- the
-fly’ DASA assay of protein mixture.
SI Video S6.
‘On the fly’ protein capture upon contacting the tagged
-antigen present at the 20
μg/ml level, in the presence of a 10
-fold excess of BSA and lysozyme proteins.
‡
These authors have contributed equally to this work.
Electronic Supplementary Material (ESI) for Nanoscale
This journal is © The Royal Society of Chemistry 2012
S
2
SI Video S7.
Anti
-proteinA antibody
-modified microengine recogniz
ing
Protein
-A from the cell
wa
ll of
Staphylococcus aureus (S. aureus)
while moving within the microchip.
SI
Video S
8.
Selective binding and transport of the small rod-
shaped (~2 μm length)
S. aureus
bacteria.
SI Video S9.
Binding and transport of a
S. aureus
target cell in a urine sample.
Electronic Supplementary Material (ESI) for Nanoscale
This journal is © The Royal Society of Chemistry 2012
S
3
Table 1
. Optimal conditions for the fabrication
of COOH-
PEDOT:PEDOT/Pt/Ni/Pt
microtransporters.
Layer
Electroplating solution
Electrochemical
conditions
COOH-
PEDOT:PEDOT
7.5 mM:7.5 mM, in 7.5 mM
KNO
3
containing 100 mM SDS
+0.85 V, 0.5 C
Pt
commercial platin
g
solution
,
see experimental section for
details
-
2 mA, 500 s
Ni
-
1.3 V,
-
4.0 C
Pt
-
2 mA, 450 s
Table 2.
Optimal conditions for the functionalization of the COOH-
PEDOT:PEDOT/Pt/Ni/Pt
microtransporters.
Parameter
Optimal value
Concentration of capture antibody / μg/ml
750
Amount of microtransporters / mg
~ 0.60 ± 0.15
Vortex speed / r.p.m
1000
Concentration of tagging antibody / μg/ml
400
Electronic Supplementary Material (ESI) for Nanoscale
This journal is © The Royal Society of Chemistry 2012
S
4
SI Figure S
-1.
Anti
-IgG
-modified microtransporter leaving the microengines reservoir (A),
passing through the interconnecting section of a linear
-shaped chip
(B)
and arriving to a second
reservoir (C), where
IgG/anti
-IgG
-modified
biotinylated
S-PPs
are present
.
Modified
microtra
nsporter navigated on this second reservoir
, c
aptured
the
S-PP-
tagged
-IgG
(D)
and le
ft
the reservoir
(E). When the microengine, coming back to the channel and
loading the tagged
analyte, found a cluster of three more S
-PP-
tagged
-proteins was able to intera
ct and pluck one of
them from the cluster
(F)
.
Electronic Supplementary Material (ESI) for Nanoscale
This journal is © The Royal Society of Chemistry 2012
S
5
SI Figure S
-2.
Modified microengine capturing and transporting a
IgG
-anti
-IgG
-modified
-PP
complex
(delineated by green circles), and
interacting (but not loading) with PP of smaller size
(delineated by
red circles).
SI Figure S
-3.
Interaction between nanomotors and AntiIgG
-IgG
-modified S
-PP, navigating in a
glass slide (A). Negative controls: PEDOT/PEDOT
-COOH (a) and PEDOT
-anti
-IgG
-incubated
nanomotors (b), respectively. Corresponding sketches for a)
and b) and modified S
-PP (B),
respectively. Contacted but unloaded particles, highlighted by an orange circle.
Electronic Supplementary Material (ESI) for Nanoscale
This journal is © The Royal Society of Chemistry 2012
S
6
SI Figure S
-4.
Anti
-IgG
-functionalized-
microtransporters displaying
an immediate ‘
on the fly’
protein
capture
upon contacting the tagged-
IgG target being present in a concentration of 20
μg/ml
in the presence of a 10
-fold excess of BSA and lysozyme proteins
(Experiments
performed on a glass slide).
IgG, BSA and lysozyme,
red rhombus,
green triangle and blue cross,
respectively.
SI Figure
S-5.
Selective binding and transport of
the
small rod
-shaped (~2 μm length)
S. aureus
bacteria
(delineated by green dotted circles)
vs
the
bigger
round-
shaped
S. cerevisiae
cells
(unlabeled,
~5 μm in diameter), unloaded even when after multiple contacts w
ith the
antiproteinA
-modifed microtransporter.
Electronic Supplementary Material (ESI) for Nanoscale
This journal is © The Royal Society of Chemistry 2012