I totally agree with Alan Bright on this.   Having been involved with the
manufacturing, QA, QC and development of what were known as the AO/Reichert and
Reichert Jung disposable microtome blades (in a past industry life), I can
attest that manufacturing a disposable blade specifically for cryostat use could
be cost prohibitive.  The entire production line would have to be switched over
to using a low temperature oil which would also have to be able to act as a
lubricant at high temperatures.   This oil would also have to not react with the
polymers used to coat the blade.  Not an easy or cheap thing to do.  I know, as
I did think of this while we were developing the blades.  It must be noted that
the oil coating on the blades is not just there to make dispensing the blade
easier but primarily for the actual production of the blade.

I would note that it will take longer (in most cases)for the OCT to freeze than
for the disposable blade to come to cryostat temperature.

best regards,
Bob
Robert Schoonhoven
Laboratory of Molecular Carcinogenesis and Mutagenesis
Dept. of Environmental Sciences and Engineering
University of North Carolina
CB#7400
Chapel Hill, NC 27599
Phone 
office 919-966-6343
   Lab 919-966-6140
   Fax 919-966-6123 

Don't go around saying the world owes you a living; the world owes you
nothing; it was here first. 
Mark Twain [Samuel Langhornne Clemens] (1835-1910) 

-- Begin original message --

> From: Alan Bright <Bright@dial.pipex.com>
> Date: Mon, 11 Oct 1999 14:51:33 +0100
> Subject: Re: Hi/low profile blades
> To: DayDawning@aol.com, jim@proscitech.com.au, PHOBOS11@aol.com,
>  histonet@pathology.swmed.edu
> 
> Dear Dawn,
> 
> I cannot see the point of keeping spare disposable blades in the
> cryochamber, as when they are placed into the blade holder they take less
> than 30 secs. to reach sectioning temperature. Plus the fact as a pack of
> blades are already very expensive, and to have this modified for cryowork
> which would be very simple, would only give an excuse to charge more.
> 
> Best Regards
> 
> Alan Bright
> 
> Bright Instrument Co.Ltd.
> St Margarets Way
> Huntingdon
> PE18 6EB
> England
> 
> Tel No:+44 (0)1480 454528
> Fax No:+44 (0)1480 456031
> Email: AlanBright@brightinstruments.com
> Web Site: www.brightinstruments.com
> 
> 
> 
> 
> -----Original Message-----
> From: DayDawning@aol.com <DayDawning@aol.com>
> To: jim@proscitech.com.au <jim@proscitech.com.au>; PHOBOS11@aol.com
> <PHOBOS11@aol.com>; histonet@pathology.swmed.edu
> <histonet@pathology.swmed.edu>
> Date: Monday, October 11, 1999 01:35
> Subject: Re: Hi/low profile blades
> 
> 
> >In a message dated 10/10/1999 9:51:27 AM Eastern Daylight Time,
> >jim@proscitech.com.au writes:
> >
> ><<  Not surprisingly a lot of people chose thicker, high profiles blades
> for
> > cryostat sectioning and thinner low profile blades for sectioning at 3 or
> >less
> > micrometers. >>
> >And another thing....
> >Why doesnt someone make a blade that is in a cryo-proof dispenser?  The
> >blades have a fine coating of oil and if left in the cryostat (like a good
> >tech should, always prepared with an extra blade, ) the oil  freezes and is
> >hard to get out of the box.
> >Dawn Truscott
> >Zeiss/Microm
> >
> 
> 
> 

-- End original message --