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Polymorphism has become a concern in today’s pharmaceutical research laboratories as it affects a number of issues in pharmaceutical systems varying from processing characteristics to bioavailability. During the pre-formulation stage of drug development, polymorph screening is a tedious and time-consuming process. Zinsser Analytic has developed CRISSY, an
automated liquid and powder handling platform
for salt pre-screening and polymorph
screening studies. This platform automates the
necessary steps for extensive crystallization
using different solvents,
temperatures, concentrations,
agitation and
pH-measurement.
A special CRISSY® reactor
block has been designed
to directly present
the crystals to the
XRPD system without
any additional sampling
steps. The surface of the
reactor base is ideal for XRPD-detection.
Cross contamination caused by electrostatic
force from moving the powders is minimized as
the detector block itself is grounded and the individual
reactor cavities are separated from
each other in the “up” position.
The reactors can be sealed with the seals and
sandwich plates of the “DESYRE®”-reactor
system. The ELAS®-mat or SILTEF®-mat
(PTFE coated) with 96 cross-slitted sealing
rings are highly recommended as the first seal
on top of the reaction cavities. An aluminum top plate secures the cross-slitted
"dimplemats",
hold down by thumbscrews for easy opening and
closing. If necessary, further sealing layers can be added, also
an inert gas shield can be added. For long term incubation –
where the pierced sealing mats may cause evaporation of the
solvents in the reactors – a solid seal can replace the septum
seals. Crissy® reactors are also available for automatic
sealing, an automatic lidding station can be provided as an
option.|
Crystallization The dry sample powders are weighed individually
with the PickFix® or Varix®-tool, with or
without a weigh-check. Reagents are added with the 2-channel filtration
probe – for sensitive
or reactive studies - together with inert gas through the 2nd channel.
The probe will penetrate
the top cross-slitted septum, which re-seals extremely well, when
the probe is retracted.
For incubation and mixing the Crissy®-reactor is transferred
to one of the DESYRE®-Mix
vortexers for heating or cooling. During vortexing the reactor
is securely clamped to the top Pictures: Click on the thumbnail to see a larger picture in a new window.
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© Copyright 2008 Zinsser NA |