From owner-biophys@hgmp.mrc.ac.uk Mon Dec 9 21:54:46 2002 Return-Path: Received: from localhost (localhost [127.0.0.1]) by mercury.hgmp.mrc.ac.uk (Postfix) with SMTP id 0D9ED7D1B5 for ; Mon, 9 Dec 2002 21:54:46 +0000 (GMT) Received: from localhost (localhost [127.0.0.1]) by mercury.hgmp.mrc.ac.uk (Postfix) with ESMTP id 64DCA7D145 for ; Mon, 9 Dec 2002 21:54:45 +0000 (GMT) Received: from niobium.hgmp.mrc.ac.uk (niobium [193.62.192.41]) by mercury.hgmp.mrc.ac.uk (Postfix) with ESMTP id 4D1B47D1B5 for ; Mon, 9 Dec 2002 21:54:44 +0000 (GMT) Received: (from news@localhost) by niobium.hgmp.mrc.ac.uk (8.9.3+Sun/8.8.8) id VAA15873 for biophys-list@hgmp.mrc.ac.uk; Mon, 9 Dec 2002 21:54:43 GMT X-Authentication-Warning: niobium.hgmp.mrc.ac.uk: news set sender to using -f From: brian.legros@epfl.ch ("Brian Le Gros") X-Newsgroups: bionet.biophysics Subject: Collagen birefringence Date: 9 Dec 2002 21:54:42 -0000 Organization: BIOSCI/MRC Human Genome Mapping Project Resource Centre Lines: 24 Message-ID: <000a01c29fcd$ce0b6300$e792b280@lmafpc160.sti.intranet.epfl.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-Complaints-To: news@net.bio.net X-Received: from localhost (localhost [127.0.0.1]) by mercury.hgmp.mrc.ac.uk (Postfix) with ESMTP id 2DA577D1B5 for ; Mon, 9 Dec 2002 21:54:41 +0000 (GMT) X-Received: from mail0.epfl.ch (mail0.epfl.ch [128.178.50.57]) by mercury.hgmp.mrc.ac.uk (Postfix) with SMTP id 33F7B7D166 for ; Mon, 9 Dec 2002 21:54:40 +0000 (GMT) X-Received: (qmail 8966 invoked from network); 9 Dec 2002 21:54:40 -0000 X-Received: from icappc160.epfl.ch (HELO lmafpc160) (128.178.146.231) by mail0.epfl.ch with SMTP; 9 Dec 2002 21:54:40 -0000 X-To: X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook 8.5, Build 4.71.2173.0 X-Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V4.72.3612.1700 To: biophys@hgmp.mrc.ac.uk Sender: owner-biophys@hgmp.mrc.ac.uk Precedence: bulk Dear List Members, My questions are in regards to quantitative polarized light microscopy. I am trying to determine the absolute retardation of a cortical bone sample and as such I need to know the difference between the fast and slow refraction indices of the component collagen fibres (type I). The best references I have at the moment suggest that the difference between the two (the actual birefringence Bmax) is approximately 0.001. Is this correct? Is it possible that anyone can state the specific difference between the refraction indices of collagen fibres or direct me to any more definitive references? Many thanks, Brian Le Gros, Laboratory of Bone Biomechanics, Ecole Polytechnique Fédérale de Lausanne, LBOS-BIOE-FSTI CH-1015 Lausanne Tél: ++41 21 693 3874 Fax: ++41 21 693 3509 --- .