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Figure S1. AFM image (non-contact mode, error signal) of TMV particles (arrow) adsorbed

on a PDMS stamp, treated for 2 s with an oxygen plasma. 0.2 mg/ml TMV suspension was

blow-dried with a stream of inert gas. In this procedure, the majority of the virions are

removed. End-to-end assemblies of TMV particles (long line-shaped objects), and some

monomers (see arrow, ~300 nm length) can be observed at the base of the raised (“positively”

structured) square-shaped feature. Again, the preference for linear end-to-end assembly is

obvious.

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This result shows that stripes are not required, rather any raised feature results in alignment of

virions at its base.

Note: Here and in the following, all AFM images of stamps are shown in error mode,

appearing illuminated from right.

Ox- PDMS 1.0 µm

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Stripe Stripe Stripe Stripe

Figure S2. AFM image (non-contact mode, error signal) of TMV particles adsorbed on a

“positively” structured (striped) PDMS stamp surface, treated for 10 s with an oxygen plasma.

0.01 mg/ml TMV suspension was allowed to dry on the surface. End-to-end assembled TMV

particles (narrow lines of > 2 µm length, see arrows) can be discerned at the bases of the

stripes. TMV prefers end-to-end alignment at the base of protruding structures of oxidized

PDMS. The raised regions of the stamp are composed of ~1.5µm wide lines and appear

rough.

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The image shows that the virions align at each raised feature and easily form lines of

micrometer length.

Ox-PDMS 2.0 µm

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Figure S3. Mobility test of TMV particles. AFM images (non-contact mode, error signal, 256

scan lines) of TMV particles (0.2 mg TMV /ml) adsorbed on a flat (featureless) stamp surface,

treated for 10 s with an oxygen plasma before adsorption. a) Before, b) after two short

contacts of the tip with the surface (each for a few scan lines).

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The scans (horizontal) where the tip was put in contact with the stamp caused local

destruction of two TMV particles (indicated by the black circles), but did not move the

dissected parts. Obviously the adhesion is so strong that lateral forces result in destruction

rather than movement. Cracks on the stamp surface are caused by the strong interaction of

AFM tip with the topmost stamp material, which can be envisaged as (brittle) silicon oxide.

(a) Ox-PDMS

500 nm 500 nm

(b) Ox-PDMS

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Stripe Stripe Stripe Stripe

Figure S4. AFM images (non-contact mode, error signal) of TMV particles (arrows) left on

an oxidized PDMS stamp surface after using the stamp a) once, b) twice to print TMV on

oxidized silicon wafers. The protruding features are ~1 µm wide stripes.

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The images show that not all virions are transferred during printing, as expected from the

transfer mechanism (even after the third printing virions were observed).

1.2 µµµµm

(a) Ox-PDMS

1.0 µµµµm

(b) Ox-PDMS

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Figure S5. Confocal microscopy of fluorescent, COOH-functionalized 50 nm spheres on Ox-

PDMS. The reflection image (left) shows the protruding line pattern of the stamp, while the

simultaneously recorded fluorescence image (right) shows maximum intensity on the flat

parts, indicating discontinuous dewetting and aggregation at the bases of the lines.

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The use of particles with a shape and size different from TMV, but with a similar surface

functionalization, suggests that a general transfer mechanism operates, which does not depend

strongly on size and shape.

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Stripe Stripe Stripe

Figure S6. AFM image (non-contact mode, error signal) of TMV particles on an oxygen

plasma treated “positively” structured stamp surface from 0.2mg/ml ethanolic suspensions of

TMV. (a) End-to-end assemblies of TMV particles generated by using a 10% ethanolic

suspension. TMV can be discernible at the base of the features (stripes) within the recesses of

the stamp structures. (b) Randomly adsorbed TMV particles generated by using 75%

ethanolic suspension of TMV (see Fig 3(b)).

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The variation of the ethanol/water ratio shows that the desired dewetting is only possible with

the more hydrophilic water-rich mixture used in (a).

1.0 µµµµm

a) Ox-PDMS

2.0 µµµµm

b) Ox-PDMS

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Stripe

Stripe

S t

r i p

e

Str.

Stripe

Stripe Str. Str.

Figure S7. Left: AFM (contact mode) image of TMV transferred to an oxidized silicon wafer

surface with a partially hydrophilic stamp. The stamp had stripe features. Right: AFM (non-

contact) image of a smaller scan area.

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The images show line features made up from attached aligned virions. The transfer

mechanism operates over large surface areas, but it is imperfect since some stripe areas

contain virions. However, the edges are much more densely covered, and show a much higher

degree of alignment.