JPK Instruments NanoWizard
®
Handbook Version 2.2a
49
when prepared fresh, but can be stored a few days in the desiccator in a dry
environment. Test the surface by imaging in air – roughness should be less than
1nm (or even lower, depending on the size of the molecules to be imaged). If the
surface is too rough, check that the APTES is clean and not old (water
contamination of the APTES stock from the air can cause aggregates to form),
check that the mica used to hold the APTES solution is clean (so there is no
contamination in the vapor), and finally try reducing the APTES amount or
incubating for only 1 - 1.5 hours.
9.3 Home made gel packs for cantilever storage
Cantilevers are delivered in plastic packages called “gel packs” of up to 50 pieces.
The chips are held on a soft and adhesive polymer layer. These gel packs can be
bought from cantilever manufacturers or can be home made for storing tips after
delivery.
Sylgard 184
®
Silicone Elastomer (Dow Corning) is often used as a pottant and
sealing for electronic parts but it can also serve for gel pack preparation. Together
with a catalyst it is delivered in aluminum containers of 1.1 kg or more.
Distributed in Germany by:
Sasco Semiconductor GmbH,
Dreieich,
06103-304552.
Instructions for gel pack preparation:
1)
The base and the catalyst have to be mixed in a precise 10 : 1 (w/w) ratio in
a glass beaker.
2)
60 g of the mixture is enough for at least 8 petri dishes (diameter 85 mm).
3)
A small amount of the mixture is poured into a dish and evenly distributed
into a thin layer by tilting the dish.
4)
Elastomer-coated dishes have to be left to polymerize for 24 hrs prior to
use. Alternatively, they can be cured at 60 °C for 3 hours.
(Information kindly provided
by D.J. Müller’s group at the
Biotechnology Center,
Technical University Dresden)
9.4 Suppliers of AFM accessories
Cantilevers, calibration grids
JPK
http://www.jpk.com
Cantilevers, calibration grids
Suppliers of AFM accessories (small parts)
TED PELLA Inc., USA
www.tedpella.com
Small parts for microscopy
Agar Scientific Ltd., England
www.agarscientific.com
Small parts for microscopy
PLANO W. Plannet GmbH Elektronenmikroskopie, Germany
Small parts, esp. for electron