Hey everyone. I'm working on a project about lichen symbiosis, and I'm
trying to prepare slides of the lichen thallus for investigation.
Unfortunately, I can't get the slices thin enough to view properly. I
need slices a few cells thick, nearly transparent. I'm using one of
those flimsy steel razor blades, and it seems to be doing alright.

Does anyone know any strategies for making really thin slices of a
specimen? Thanks a bunch!

-Nitrobacter

Nitrobacter schreef
Hey everyone. I'm working on a project about lichen symbiosis, and I'm
trying to prepare slides of the lichen thallus for investigation.
Unfortunately, I can't get the slices thin enough to view properly. I
need slices a few cells thick, nearly transparent. I'm using one of
those flimsy steel razor blades, and it seems to be doing alright.

Does anyone know any strategies for making really thin slices of a
specimen? Thanks a bunch!

-Nitrobacter

+ + +
I am sure a Google search will turn up lots of techniques for this.
Basically:
1) a knife must be very sharp.
2) the material must be as soft as possible
3) In cutting, free movement of knife and material is to be restricted.
Don't use a flimsy razor blade, you 'd be better off with a snap-off knife.
Use (hot) water to soften the material. Clamp the material if necessary.
Cut, don't push.
PvR

Just to elucidate on PvR's clamp, the classic technique is the use of
the pith from? It is sliced lengthwise and the material inserted into
it. An available substitute that should work on lichen thalli is a piece
of carrot. The little carrots sold in bags ought to work nicely.

Gene

P van Rijckevorsel wrote:

Nitrobacter schreef


Hey everyone. I'm working on a project about lichen symbiosis, and I'm
trying to prepare slides of the lichen thallus for investigation.
Unfortunately, I can't get the slices thin enough to view properly. I
need slices a few cells thick, nearly transparent. I'm using one of
those flimsy steel razor blades, and it seems to be doing alright.

Does anyone know any strategies for making really thin slices of a
specimen? Thanks a bunch!

-Nitrobacter



+ + +
I am sure a Google search will turn up lots of techniques for this.
Basically:
1) a knife must be very sharp.
2) the material must be as soft as possible
3) In cutting, free movement of knife and material is to be restricted.
Don't use a flimsy razor blade, you 'd be better off with a snap-off knife.
Use (hot) water to soften the material. Clamp the material if necessary.
Cut, don't push.
PvR

Gene Newcomb schreef
Just to elucidate on PvR's clamp, the classic technique is the use of the pith from ...

+ + +
that would be Sambucus, elder
+ + +

It is sliced lengthwise and the material inserted into it. An available substitute that should work on lichen thalli is a piece of carrot. The little carrots sold in bags ought to work nicely.

+ + +
Or Styrofoam, in one of the denser grades
PvR

"P van Rijckevorsel" wrote in message .. .
Gene Newcomb schreef
Just to elucidate on PvR's clamp, the classic technique is the use of
the pith from ...

+ + +
that would be Sambucus, elder
+ + +

It is sliced lengthwise and the material inserted into it. An
available substitute that should work on lichen thalli is a piece of
carrot. The little carrots sold in bags ought to work nicely.

+ + +
Or Styrofoam, in one of the denser grades
PvR

A microtome is an instrument your ingenuity might perhaps be able to
improvise. Movement of either blade or specimen (in elder-pith, etc)
is done by turning a screw, so you can get finer adjustment than the
unaided human hand could manage. At least one of the older books on
microscopy gave instructions for making a non-improvised durable one,
but I'm afraid I can't remember which, and I haven't got it any more.

Mike.

Mike Lyle schreef
A microtome is an instrument your ingenuity might perhaps be able to
improvise. Movement of either blade or specimen (in elder-pith, etc)
is done by turning a screw, so you can get finer adjustment than the
unaided human hand could manage. At least one of the older books on
microscopy gave instructions for making a non-improvised durable one,
but I'm afraid I can't remember which, and I haven't got it any more.

+ + +
The OP could not even find proper razor blades, so a microtome likely is
lightyears beyond him. Besides that this is just the sort of project where
sections made by the unaided human hand could indeed be better than those
from a microtome.
PvR

For smaller mosses. I use a binocular microscope, a thin razor and pretend it's
a microscopic version of slicing veggies. It helps to keep one end of the blade
steady on the slide, as if one were using a French knife.

It takes some practice, but free-hand sections work a lot better than trying to
fish lichen thalii from masses of elder-pith. At least if you're not working
with crustose apothecia.. Then one really needs a more useful technique.

Christine Manville