The EMS


in practice


The EMS POLY III instrument is capable of effectively removing any of the solvents commonly used in embedding as long as the following rules are observed:


• use small tissue pieces, smaller volume of cell pellets • use separate programs for embedding and polymerization • use the smallest amount of resin in the embedding step


• during polymerization do NOT lower the pressure to a level equal to or lower than the saturated vapor pressure as any trace amount of sol- vent will result in the formation of holes in the specimen


Small specimens are more easily embedded because of their favorable surface/volume ratio. Likewise, solvents are more easily extracted.


Along those lines it is obvious that solvent is more easily removed if the specimens are covered (or even just merely contained) in a minimum amount of resin. For instance, when using BEEM capsules it is typically sufficient to end up with 30-50 µI of resin at the end of the embedding run.


Using a dilute resin/solvent mixture, or a small volume of mixture in the embedding program leaves the specimens covered in a thin layer of resin by the end of the embedding run, just enough to cover or contain the specimen.


A procedure that has been tested for embedding yeast cells is described below and may serve as a starting point.


Yeast cells were fixed with glutaraldehyde in cacodylate buffer, washed in distilled water and postfixed with 1% KMn04 in distilled water.


After washing in distilled water the cells were dehydrated in a graded series of solvent/water mixtures: 50% - 70% - 80% - 90% -100% - 2xl00% absolute. Each step lasted 10min.


Cells are then resuspended in resin/solvent 1:10 (v/v) and after 10 min. pelleted. The pellet is resuspended in fresh mix (appr 1Ox the volume of the pellet) and then transferred into one or more BEEM capsules.


front panel


It is strongly recommended to transfer the suspension into BEEM vials OUTSIDE the POLY III vacuum recipient to avoid spilling of resin inside the recipient. Any spilled resin on the vials should also be removed before inserting the BEEM vials into the recipient recessions.


Once all the BEEM vials have been transferred, the embedding program can start. The embedding program is followed by the polymerization program, after the BEEM vials have been topped up with pure resin.


Alternately, silicone molds can be used in the polymerization program. back panel


Specifications 5 programs, up to 5 steps each Temperature of the Sample Block


Temperature set point in increments of 1 deg C. Temperature Control Accuracy at the Sensor:


Sample Block:


Sample Block for BEEM Capsules, silicone molds Vacuum Level:


sample block holds up to 52 samples


10 – 70 deg C.


+/- 2.0 deg. C in heat mode, +/- 3 deg. C in cooling mode. Up to 52 samples


Introduction of fresh air during vacuum cycle and flush cycle. Lid for the Processing Block:


10kPa (or 3” of Hg at sea level) – 100kPa Anodized aluminum with plastic cover


Heated Lid 2 line x 16 character LCD Display with 6 keys membrane keypad Thermoformed Enclosure Dimensions: Weight:


Power Requirements: Fuse:


9” wide (23 cm) wide x 20” (51 cm) deep x 11” (28 cm) tall (with lid) 21 lbs (10 Kg)


200 watts max, 100 – 240 volts AC, 50 or 60 Hz 2.5 Amp x 250 VAC, Time Delay/Slo Blo fuse


4444


Ordering Information Cat No. Description EMS Poly III


70020-B


70900 70901 70902


BEEM® Embedding Capsules Size 00


Polyethylene embedding capsules with 1x1mm face at the tip of a truncated pyramid, each with a hinged cap.


Standard flat embedding mold, 21 numbered cavities measures: 14mm(L) x 5mm(W) x 4mm(D). (clear silicone) each


Same as #70900, but each of the 21 numbered cavities measures: 14mm(L) x 5mm(W) x 6mm(D). (white silicone) each


Same as #70900, but each of the 21 numbered cavities measures: 14mm(L) x 5mm(W) x 3mm(D). (white silicone) each


Qty. each


1000/pk


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6