Paraffin Wax Embedding

1. Immerse sample in 70% ethanol for two minutes.
2. Remove excess liquid and immerse the sample in 95% ethanol for two minutes.
3. Remove excess liquid and immerse sample in absolute ethanol for two minutes.
4. Remove excess liquid and immerse the sample in fresh absolute ethanol for two minutes.

What is the paraffin technique?

What is the paraffin technique? In this technique, tissues are fixed, and embedded in wax. This makes the tissue hard, and much easier to cut sections from. The sections are then stained, and examined with the light microscope.

Why is paraffin used for embedding?

The most widely used embedding medium for biological applications is paraffin wax, or ‘paraffin. ‘ Paraffin wax is insoluble in water but dissolves in toluene and xylene and melts at 46–68 °C, making it an ideal medium for embedding tissues after they have been dehydrated.

How do you prepare tissue for paraffin embed?

Overview of the steps in tissue processing for paraffin sections

1. Obtaining a fresh specimen. Fresh tissue specimens will come from various sources.
2. Fixation. The specimen is placed in a liquid fixing agent (fixative) such as formaldehyde solution (formalin).
3. Dehydration.
4. Clearing.
5. Wax infiltration.
6. Embedding or blocking out.

What is Celloidin technique?

Celloidin Embedding The tissue is dehydrated in alcohol in the same way as for paraffin except that it is transferred from absolute alcohol to a dilute solution of celloidin. As the alcohol and ether evaporate, they are replaced by more concentrated celloidin.

How is embedding done?

Embedding is the process in which the tissues or the specimens are enclosed in a mass of the embedding medium using a mould. Since the tissue blocks are very thin in thickness they need a supporting medium in which the tissue blocks are embedded. This supporting medium is called embedding medium.

What are the most common methods of embedding?

For light microscopy observation, paraffin is the most common embedding substance. Celoidine is another embedding medium for light microscopy. For electron microscopy, epoxy and acrylic resins are the most used embedding substances.

What is Celloidin embedding?

Celloidin Embedding Celloidin is dissolved in equal parts of absolute alcohol and ether. It is finally hardened in chloroform and stored in 80 percent alcohol. It is a much longer process than paraffin but causes much less shrinkage and distortion. It is used especially in examination of the eye and brain.

Why is paraffin technique important?

It minimizes the loss of tissue during vigorous processing procedures, allows placement of multiple small tissues within one block, and provides orientation for sectioning. Arrange tissues on a glass slide, with the region of interest in contact with the slide surface. c.

What is the most important step in embedding?

Correct orientation of tissue in a mould is the most important step in embedding. Incorrect placement of tissues may result in diagnostically important tissue elements being missed or damaged during microtomy.

What is the best dehydrating agent?

The most commonly used Dehydrating agent is Ethanol because of its reliability, cost-effectiveness and excellent dehydration properties.

What is the difference between impregnation and embedding?

Impregnation is the process of complete removal of clearing reagents by substitution of paraffin or any such similar media such as beeswax. After complete impregnation with a suitable medium, solid block of suitable medium containing impregnated tissue is obtained by a process called embedding.

Are formalin fixed tissues infectious?

There appears, however, to be an assumption that formalin-fixed tissue poses little or no risk of infection . This is evident from the paucity of information on this topic in the medical literature and from the lack of guidelines concerning the safe handling of formalin-fixed tissue that is infected with TB.

What is paraffin embedded tissue?

Paraffin Embedded tissue allows the tissue sample to be cut into a slice as little as 1-2 cell layers thick. tissue sections are fixed in formalin immediately post excision and embedded in IHC-grade paraffin.

What are paraffin blocks?

WaxWel Paraffin Blocks are designed to be used in all paraffin units and assist with providing heat therapy to the hands, wrists, ankles, or feet. The paraffin blocks are heated in a paraffin bath and help treat patients suffering from pain associated with arthritis, strains, sprains and joint… more info.