Water baths are a very common element in any type of microbiological laboratory. This type of equipment is a container that is able to retain hot water to incubate samples in water at a constant temperature for a prolonged period. Water baths generally have an interface that allows the user to set the correct temperature to achieve the desired results.
There are some essential steps in a histology laboratory. The sectioning process is one of the most important, since this procedure has to be very precise and the blocks you are cutting should not be broken in any way. When the cutting process begins, the first thing to do is cool the paraffin blocks to make the correct cut. The blocks are then placed in the water bath and programmed at the desired temperature, being a fundamental step in the entire procedure.
How does it work?
A flotation bath or water bath is the intermediate step between cutting paraffin sections and placing them on slides. A warm water bath allows the tissue to relax and soften before being placed on a glass slide. The heat also causes the paraffin to adhere to the glass slides.
Water baths are filled with distilled water, heated at a temperature of 5-10 ° C below the melting point of paraffin, and the water bath is generally maintained at 40-50 ° C. This is an optimal temperature range for various types of paraffins. Hard paraffin will require a higher water temperature to relax, while softer paraffins will benefit from a lower water temperature as they can disintegrate at higher temperatures.
Usefulness of the water bath in the histology laboratory:
After making the successive cuts of the block thanks to the microtome, the tissues shrink in this way, they could not be placed directly in the object holder.
The basic function of the water bath or flotation is to extend the fabric strip so that it subsequently adheres to the lamella. In this device a substance must be placed so that the tissue is stretched, such as: water, unflavored jelly, etc.
The importance of the flotation bath is that it helps the fabric slats to be extended, to later catch them and that they are fixed to the object holder.
Recommendations for use:
- Used to float paraffin ribbons, to stretch sections and eliminate wrinkles and folds before placing sections on the slide.
- 95% alcohol can be added to the water to reduce surface tension and eliminate wrinkles.
- It may be necessary to lower the water temperature for fatty tissue, such as the breast or brain.
- Sometimes adhesive is added to the water to aid in the adhesion of the slide.
- Water should be kept clean and changed at least daily.
- Keep the empty tank covered to prevent fibers and dust from depositing and becoming a potential contaminant.
- The tank must be cleaned daily and the paraffin must be removed with gauze. It can also be cleaned with alcohol.
- The surface of the water should be skimmed with a laboratory wipe to avoid contamination of debris between each tape.
- A water bath that is too cold will not eliminate wrinkles in the tissue sections.
- A water bath that is too hot can melt the paraffin and change the morphology of the tissue.
- The water bath can introduce artifacts into the sections.