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Sample Preparations
Cryo-fixation
Contact & Support
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HPM 010 High Pressure Freezing Machine
The Proven High Pressure Freezing
Machine
With over 100 installations
world-wide, and more than 400 scientific
publications to its credit, the HPM-010 is not only
the pioneer of HP freezing, but the instrument of
choice which allows freezing of aqueous samples up
to 200µm thickness without visible ice crystal
damage and without the use of cryo-protectants.
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Key Features
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Freezing of specimens up to 200µm thickness
and 2mm diameter without visible ice crystal damage
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No need for cryo-protectants
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Cryo-fixation of suspensions, monolayer cell
cultures and tissue
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Short handling time before freezing
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Reproducible freezing
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Easy one button operation
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Large base of application know-how available
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Features / Benefits
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Highest quality freezing of tissue samples in
thickness ranges of up to 0.2 mm without requiring freeze
protective additives.
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Array of specimen carriers available, i.e.
for suspensions (capillary tubes), tissue extracted by fine
needle biopsy and carriers for monolayer cell cultures.
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In-situ real time measurement of temperature
and pressure.
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Fast 90-second process cycle allows
expeditious application.
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Automatic, microprocessor controlled
operation for routine work.
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Compact, sturdy unit with soundproof and
vibration-free housing.
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Simple and safe operation due to
quick-locking action of specimen holder and clearly arranged
operational controls.
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Processing datas are recorded on digital
display, such as the actual temperature, time and pressure,
thus allowing the user to exactly evaluate current
operational status (sample quality control).
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Officially approved materials and
high-pressure components, as well as twice controlled sample
holders with quick-lock action ensure highest level of
safety for user.
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Simple maintenance with removable cover
plates and rack system for control units.
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Extensive accessory program.
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Large number of publications documenting high
performance of HPM 010.
Applications
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Freezing of large tissue specimens without
requiring structure-altering freeze protective additives.
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Ideally suited for subsequent replication by
freeze fracturing in a freeze etching system for TEM
applications or subsequent
cryo sectioning for cryo SEM and TEM investigations.
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Best suited in conjunction with subsequent
freeze substitution, followed by low temperature embedding
and polymerisation for sectioning in a conventional ultramicrotom.
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Suitable for samples destined for subsequent
thin sectioning in their frozen state by cryo-ultramicrotom for cryo - TEM analyses.
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For samples intended for subsequent
freeze-drying and SEM or TEM
investigations.
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The High Pressure Freezing Method
Excellent freezing of the specimens intended for examination in the
electron microscope is one of the most important prerequisites for
achieving reproducible results from the various subsequent
cryopreparation methods.
The freezing method should produce microcrystalline or amorphous ice
from the specimen water. To achieve this, the specimens must be
frozen as quickly as possible at a freezing rate no lower than 10’
000°C/s.
The conventional freezing methods in use are plunge freezing, jet
spray and cold block (slamming) cryo fixation. However, due to the
poor heat conductance of water, these methods can only
satisfactorily freeze specimens measuring up to between 10 and 20µm.
Thicker specimens (such as tissue samples) could only be frozen in
the past, if a cryoprotectant was added to lower the freezing point
of the water in the specimen. The disadvantage of chemical
cryoprotectants is that they often affect certain cell structures,
causing different types of undesirable artefacts.
By using the high pressure freezing method developed by Prof. Moor
(ETH Zurich) in conjunction with BAL-TEC AG these artefacts can be
eliminated. The high-pressure method is based on an entirely
physical phenomenon that lowers the freezing point of water. This
method functions as follows: At 2’ 100 bar the melting point of
water drops from 0°C to -22°C. Under normal atmospheric conditions
homogeneous nucleation (supercooling) begins at -40°C. Under high
pressure this nucleation doesn’t begin until the water has reached
-90°C (see H20 Phase Diagram).
At 2’ 100 bar water is 1’ 500 times more viscous than at atmospheric
pressure, which drastically reduces the nucleation and thus the
crystal growth rate. This means that the extremely high freezing
rate (min. 10’ 000°C/s
required for satisfactory freezing by the methods previously
mentioned is not necessary with the high pressure method. The high
pressure method allows specimens up to 0.2mm thickness with a total
volume of approx. 1mm 3 to be vitrified or up to 0.5mm thickness to
be adequate frozen at a low freezing rate of 200°C/s
without requiring the addition of cryoprotectants.
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