Tissue dealcoholizationis an innovative and transformative technique in the field of biological research and medical applications.
It’s gaining increasing attention for its ability to revolutionize the way we study, preserve, and utilize biological specimens.
In recent years, scientists and medical professionals have been exploring various methods and uncovering a plethora of benefits associated with tissue dealcoholization.
In this article, we will delve into the methods and benefits of tissue dealcoholization, shedding light on the potential it holds for scientific and medical advancements.
In the context of alcoholic beverages, dealcoholization refers to a process used to remove or reduce the alcohol contentfrom a liquid while retaining the flavor and other desirable characteristics of the beverage
This process is typically employed to create non-alcoholic or low-alcohol versions of alcoholic drinks.
Two persons with each of their arms on a table and holding a glass of non-alcoholic beer and wine
By doing so, individuals who wish to avoid or limit their alcohol consumption can have the opportunity to enjoy the taste of these beverages without the intoxicating effects.
Dealcoholization can affect the flavor, aroma, and mouthfeel of the beverage.
Therefore, manufacturers often take steps to re-blend or adjust these attributes to match the original product as closely as possible.
Now what about tissue dealcoholization?
To explore that field, we need to first discuss tissue processing.
Tissue processing refers to a series of laboratory techniques and procedures used in the preparation of biological tissues for various applications, including:
The primary goals of tissue processing:
- to preserve tissue samples
- make them suitable for microscopic examination
- extract relevant information
Here are the key steps involved in tissue processing, which can give us a bit of an idea about tissue dealcoholization:
Tissues are typically fixed with a chemical solution (e.g., formalin) to preserve their structural integrity and prevent decay.
This fixation step is typically performed with alcohol-based solutions like formalin, which contains ethanol.
After fixation, the tissues contain a significant amount of alcohol from the fixative.
Dehydration is the process of gradually removing this alcohol and replacing it with a substance that can be easily infiltrated by paraffin wax.
Ethanol alcohol from a white plastic container being poured into a 1,000- milliliter Erlenmeyer flask
Tissues are dehydrated by passing them through a series of alcohol (ethanol) solutions of increasing concentration. This process is crucial to prepare the tissues for embedding in paraffin wax.
Paraffin wax is a white or colorless soft solid derived from petroleum, coal, or shale oil. It has many uses, such as in candle making.
After dehydration, the tissues are immersed in a clearing agent to further remove any remaining alcohol and make the tissues more transparent.
This step ensures that the tissue becomes more compatible with the embedding medium.
Once the tissues are adequately cleared, they are infiltrated with molten paraffin wax.
This infiltration process replaces the clearing agent within the tissue with paraffin wax, which eventually solidifies, providing support and stability to the tissue.
This step allows the tissue to be cut into thin sections for microscopic examination.
The infiltrated tissues are placed in molds, and molten paraffin wax is poured over them.
As the wax cools and solidifies, it encapsulates the tissue, forming a paraffin block.
The paraffin blocks with embedded tissues are cut into thin sections using a microtome.
These sections are typically mounted on glass slides and are ready for staining.
Tissue sections may be stained with various dyes or reagents to highlight specific structures or components (e.g., cell nuclei and proteins).
Different stains serve different purposes, including identifying abnormalities or specific cell types.
After staining, the tissue sections are mounted on glass slides and covered with a coverslip using a mounting medium (e.g., mounting media or mounting fluid).
This preserves the stained tissue for microscopic examination.
As alcohol has been mentioned, we get closer to learning about tissue dealcoholization.
Dealcoholization is a specific step within tissue processing, and they are interconnected in the workflow of tissue sample preparation.
Tissue processing and dealcoholization are related concepts in the context of preparing biological tissue samples for various laboratory applications, including histology and molecular biology.
Dealcoholization in tissue processing or tissue dealcoholization refers to a technique used in histology.
This technique is employed to remove alcohol (usually ethanol) from tissue samples that have been preserved in alcohol (typically either formalin or ethanol), for various research and diagnostic purposes.
This step is essential to prepare tissue samples for embedding in paraffin wax or other embedding media and subsequent sectioning for microscopic analysis.
Tissue dealcoholization is a crucial part of histology and pathology, as it allows researchers and pathologists to:
- study the structural and cellular details of tissues
- diagnose diseases
- conduct research on various aspects of biology and medicine
We’ll discuss further the benefits of tissue dealcoholization in the next heading.
The quality of tissue processing plays a significant role in the accuracy and reliability of the results obtained from these studies.
Here’s a more detailed explanation of tissue dealcoholization and how it differs from the dealcoholization process used in alcoholic beverages:
1. Tissue Preservation
When we talk about tissues, they involve these things:
- biopsies (medical procedures where a tissue sample is needed)
- other biological samples
Tissues are often preserved in alcohol-based solutions to prevent:
- microbial growth
- autolysis (self-digestion of tissues)
Commonly used preservatives include formalin and ethanol.
While these solutions effectively fix the tissues for long-term storage, they can interfere with subsequent processing and analysis.
2. Dealcoholization in Histology
Dealcoholization in histology is the process of removing the alcohol-based fixative from tissue samples while maintaining the structural and chemical integrity of the tissues.
This step is essential for further analysis, including staining and microscopy.
Since this term will be mentioned a lot of times here, let’s define “microscopy.”
It’s a scientific technique used to observe and study objects or specimens that are too small to be seen with the naked eye. Therefore, it involves the use of microscopes.
A female scientist in white lab gown and blue nitrile gloves examining a tissue under a microscope
3. Steps in the Dealcoholization of Tissue
The process of tissue dealcoholization involves a series of graded alcohol solutions, which gradually replace the original fixative.
The steps may include:
a. Rinsing the tissue in decreasing concentrations of alcohol to remove the fixative.
b. Rehydrating the tissue with water to remove any remaining alcohol.
c. Transitioning the tissue into a medium suitable for the intended analysis, such as paraffin or resin for embedding and sectioning (used for microscopy).
4. Relationship to Alcoholic Beverages
The use of the term “dealcoholization” in histology is unrelated to the process used for alcoholic beverages.
As mentioned earlier, dealcoholization also refers to the removal or reduction of alcohol content in drinks (wine and beer), to create non-alcoholic and low-alcohol versions.
That one is a completely different process from tissue dealcoholization, which concerns the removal of alcohol fixatives from tissue samples in histology.
The importance of preserving tissue samples has far-reaching implications for:
Dealcoholization of tissue can have several benefits, each of which serves specific research or clinical purposes.
Here are some of the benefits of tissue dealcoholization:
a. Improved Preservation
Removing alcohol from tissue samples helps preserve the biological material for longer periods.
Alcohol, particularly ethanol, is commonly used as a tissue fixative and preservative. If you need the tissue samples for histological analysis (e.g., microscopy), alcohol is an effective fixative.
It helps prevent tissue decay and bacterial contamination.
However, even though alcohol can act as a preservative, it can also alter the structure and composition of the tissue over time.
Dealcoholization ensures that the tissue retains its original characteristics and remains suitable for various analytical techniques.
b. Reduced Interference in Assays
In many laboratory assays and analytical methods, the presence of alcohol can interfere with accurate results.
For example, alcohol can affect the enzymatic activity, protein denaturation, or other chemical reactions within the tissue.
Through tissue dealcoholization, these interferences can be minimized, allowing for more precise experimental outcomes.
c. Better Histological Staining
Alcohol in tissue samples can affect the quality of histological staining, making it challenging to visualize tissue structures under a microscope.
Removing alcohol enhances the clarity and resolution of histological images, which is essential for diagnosing diseases or studying tissue morphology.
d. Compatibility with Specific Analytical Techniques
Certain analytical techniques and instruments require samples that are free of alcohol. They include these two:
- mass spectrometry
- NMR (nuclear magnetic resonance) spectroscopy
Tissue dealcoholization ensures that tissue samples are compatible with these techniques, enabling researchers to gather accurate and reliable data.
e. Improved Gene and Protein Analysis
Alcohol can degrade nucleic acids (DNA and RNA) and proteins within tissue samples, making them less suitable for genetic or protein analysis.
The process of dealcoholizing tissue helps maintain the integrity of these molecules, allowing researchers to study gene expression and protein profiles accurately.
f. Enhanced Cell Viability for Cell Culture
In cell culture studies, researchers often need to isolate and culture cells from tissue samples.
Alcohol can be toxic to cells, affecting their viability and growth.
Through tissue dealcoholization, the isolated cells are more likely to remain healthy and viable for longer periods, improving experimental outcomes.
g. Minimized Artifacts
Alcohol can introduce artifacts into tissue samples, which are abnormal structures or features created during sample preparation.
Dealcoholization of tissue reduces the risk of these artifacts, ensuring that research findings are based on the actual tissue characteristics and not on artificial alterations.
h. Ethical Considerations
In some cases, alcohol is used as a fixative in the preservation of tissue samples.
However, using alternative methods for dealcoholization may align with ethical concerns, particularly in research involving human or animal tissues.
Researchers may opt to remove alcohol to avoid potential harm to human or animal donors.
All in all, tissue dealcoholization is essential in various research and clinical applications to ensure:
- the preservation of tissue integrity
- compatibility with specific assays and techniques
- the generation of accurate and reliable data
It also helps reduce potential ethical concerns related to the use of alcohol as a fixative.
According to an article published by Bowling Green State University, yes, when you consume alcoholic drinks, the alcohol you ingest is absorbed into your bloodstream through your stomach’s tissue lining.
Here’s how the process generally works:
A young guy drinking canned beer, with a middle-aged guy behind him giving a peace sign
Most of the alcohol absorption occurs in the small intestine.
Per nidirect.gov.uk, Northern Ireland’s website, the amount of alcohol absorbed is 20 percent.
Alcohol can pass through the walls of the stomach and into the bloodstream, but it’s primarily absorbed in the upper part of the small intestine.
Once absorbed into the bloodstream, alcohol is distributed throughout the body, affecting various tissues and organs.
- cognition/reasoning (your judgment becomes impaired)
The liver plays a crucial role in metabolizing alcohol.
It breaks down alcohol into substances that can be eliminated from the body. This process is carried out by enzymes in the liver.
After metabolism, the byproducts of alcohol are excreted from the body primarily through the kidneys, in the form of urine.
A small amount of alcohol is also eliminated through the breath and sweat.
Clearing agents are substances or chemicals used in laboratory settings to clear or make transparent specimens for microscopy or other analysis.
Per LabCE, they’re also referred to as:
- dealcoholization agents
Based on the study Comparison between Xylene and Coconut Oil in Tissue Processingpublished by Modern Medical Laboratory Journal in 2019, here are some types of clearing agents:
- citrus fruit oils (e.g., lemon oil and orange oil)
- chloroform (can make tissues more transparent, allowing for better visualization of cell structures when viewed under a microscope)
- methyl benzoate
- methyl salicylate (derived naturally from wintergreen plants; also known as oil of wintergreen)
According to Paramedics World, as a clearing agent, it’s good but not usually used as one. The following clearing agents aren’t commonly used in such capacity:
- benzene (this one is “rarely used” because it can likely cause cancer)
- carbon disulfide
- cedarwood oil (its penetrating rate is “slow,” that’s why even if it’s an “excellent” clearing agent, it’s not often used as one)
- clove oil
Paramedics World identified three advantages of using xylene:
- it quickly removes alcohol
- mixes well and fully dissolves with alcohol
This groundbreaking approach called tissue dealcoholization offers a promising avenue for improving the quality and usability of biological tissues.
Dealcoholization is a critical part of the tissue processing workflow because it ensures that the tissue is adequately preserved, dehydrated, and prepared for embedding in paraffin wax.
All these mentioned are essential for producing high-quality histological sections that can be examined under a microscope.
Therefore, by advancing the understanding of tissue dealcoholization, we can improve on various biological processes, enhance medical treatments, and preserve invaluable specimens for future generations.