Dear Yohannes,
Lyophilization or just vacuum drying at slightly elevated temperature will
remove water in many cases down to 0.1% (1 molecule water in a compound with
a FW of 350 is 5%). You may change the crystal structure. DSC-data will be
helpful to get information about irreversible damage. Drying of proteins
down to 0.1% may cause irreversible damage.
Gert Eberlein, Ph.D.
Analytical Method Development
Santen Inc
Tel.: (707) 256 2405
Fax: (707) 254 1760
Geberlein@Santen-Inc.com
-----Original Message-----
From: MODERATOR
Sent: Tuesday, January 12, 1999 1:37 PM
To: PharmSciTech
Subject: Removing cystalline water from organic substances
Dear Forum Members,
Let's say we have organic substance having chemically bound water (=
crystalline water) = X.nH20.
Is there any specific method to remove that water without damaging
the
molecule its self ?
My experience : using conventional heating (i.e. 100 C), the water
could
be removed but the material showed colour change.
Yohannes Sutasurya
ysutasurya@kalbe.co.id
to: IN:PharmTech@www2.pharmweb.net
cc: pas
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