Extraction of poison from biological materials

        Poison extraction from biological material is a method of isolating harmful chemicals from living organisms or their metabolites. It is critical to stress that extracting toxins from biological material should only be done by qualified specialists in controlled surroundings like research facilities, and always with sufficient ethical considerations. Attempting to extract poisons without proper training can be extremely risky, resulting in injury to the extractor or observers. There are different methods for extraction of poisons are define below;

1) Dry-aching method: - Dry aching is very useful for organic-rich samples such as biological tissues, food products, and environmental materials. The approach accurately determines inorganic elements present in the sample by eliminating organic materials by burning. Here is a basic outline of the dry aching method:

• Sample preparation: - The sample is prepared by carefully drying it to remove any moisture. To enhance the surface area for more efficient aching, the sample might be ground or crushed.
• Aching Furnace: - The dried sample is placed in an aching furnace. Depending on the materials of interest, the furnace is designed to attain high temperatures, often exceeding 500 degree C and up to 1,000 degree C or more.
• Combustion: - In an oxygen rich atmosphere, the sample is subjected to controlled burning. Organic components are oxidizing during burning, and volatile chemicals are liberated as gases. Inorganic residues or ashes are what remain.
• Cooling: - The furnace is allowed to cool after combustion. Inorganic residues are frequently white or light colored.
• Residue collection: - The ash sample is taken from the furnace. Depending on the needs of the analysis, the residue may be subjected to additional treatment or dissolved in a suitable solvent.
• Analysis: - The inorganic remains can now be studied using various analytical techniques because they are no longer contaminated with organic components. Atomic absorption spectroscopy, inductively coupled plasma optical emission spectroscopy, and inductively coupled plasma mass spectrometry are all common approaches.

2) Acid digestion method: - Acid digestion is commonly used in environmental analysis, food analysis, geological studies and other domains where the elemental composition of solid material must be precisely evaluated. It is crucial to choose the appropriate digestion acids and conditions based on the sample properties and analytical objectives. Precautions should also be taken to prevent contamination throughout the digestion process. Here's an overview of the acid digestion procedure;

• Sample preparation: - The solid sample if necessary, mashed or crushed to enhance surface area for better digestion.
• Selection of digestion acid: - By the type of the sample and the constituents of interest the acid is used. Nitric acid (HNO3), Hydrochloric acid (HCL), Sulfuric acid (H2SO4) and a combination of these acids are often used acids.
• Digestion procedure: - The sample is heated under controlled conditions using the appropriate acid(s). The acid(s) dissolve both the inorganic components and the matrix of the sample. Typically, digestion occurs in specialised digestion vessels such as Teflon or quartz digestion vessels.
• Heating and Evaporation: - To aid digestion, the sample and acid mixture are heated, generally on a hot plate or in a digestion block. To concentrate the sample, the solution can be evaporated if necessary.
• Cooling and Dilution: - The solution is allowed to cool after digestion. To acquire the necessary concentration for analysis, it can then be diluted to a known volume with deionized water or another suitable solvent.
• Filtration: - can be used to remove any undissolved particles or insoluble residues from the solution.
• Analysis: -The resultant solution, which now contains the dissolved elements of interest, can be quantified using the appropriate analytical technique e.g., AAS, ICP-OES, ICP-MS.

Instrumentation

    By assessing the presence of poisonous chemicals in biological samples, forensic toxicology plays an important role in the investigation of poisoning cases. Forensic toxicology instrumentation has advanced significantly, enabling for more accurate and sensitive detection of numerous toxins. Here are some of the most important tools and approaches utilized in the field;

a) Gas chromatography: -

• Principle: - Volatile compound separation based on affinity for a stationary phase.
• GC is often used to analyze volatile organic substances such as medicines and volatile toxins.

b) Liquid chromatography: -

• Principle: - Non-volatile and semi-volatile chemicals are separated based on their interactions with a liquid mobile phase and a solid stationary phase.
• LC is versatile and can be used to analyze a wide variety of molecules, including medicines, insecticides, and other dangerous substances.

c) Mass spectroscopy: -

• Principle: - Identifies compound based on their mass to charge ratio.
• Application: - Combining chromatography with mass spectroscopy improves the specificity and sensitivity of toxicological investigations, allowing specific poisons to be identified.

d) High performance liquid chromatography: -

• Principle: - A more advanced type of liquid chromatography that employs high-pressure pumps to provide more rapid and effective separations.
• HPLC is commonly employed in forensic toxicology for the analysis of drugs and other substances.

e) Inductively coupled plasma mass spectrometry: -

• Principle: - The detection of elements in an inductively linked plasma source is dependent on their mass to charge ratio.
• ICP-MS is used for metal and metalloid analysis, providing information on elements such as arsenic, lead and mercury.

f) Enzyme linked immunosorbent assay (ELISA): -

• Principle: - Enzyme linked reactions are used to detect specific antigens or antibodies.
• ELISA is frequently used for the fast screening of medicines or poisons in biological material.

g) Nuclear magnetic resonance (NMR): -

• Principle: - The detection of signals from atomic nuclei in a magnetic field to determine the structure of compounds is the principle.
• Toxin identification and structural elucidation can be accomplished using NMR spectroscopy.

h) Tandem mass spectrometry: -

• Principle: - Increasing specificity through successive steps of mass spectrometry.
• MS/MS is useful for targeted analysis since it allows for the identification and quantification of individual substances with great precision.

References: -

1. https://www.ojp.gov
2. http://www.emedicinehealth.com
3. https://www.msdmanuals.com
4. https://www.hopkinsmedicine.org
5. https://www.ncbi.nlm.nih.gov