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CHM.310465 - Sodium hydroxide - ACS reagent, ≥97.0% - CAS: 1310-73-2
Sodium hydroxide (NaOH), with the Chemical Abstracts Service (CAS) number 1310-73-2, is a highly versatile and widely used chemical in molecular biology. It is a strong base with the ability to alter pH, denature proteins, and hydrolyze nucleic acids, making it indispensable in various laboratory protocols. Below is a detailed overview of the molecular biology applications of sodium hydroxide:
1. pH Adjustment in Buffer Preparation
Sodium hydroxide is commonly used to adjust the pH of buffers and solutions in molecular biology. Examples include:
  • Tris Buffers: NaOH is used to titrate Tris (tris(hydroxymethyl)aminomethane) to the desired pH, typically between 7.0 and 9.0, for use in electrophoresis, cell culture, and enzyme assays.
  • Phosphate Buffers: NaOH is used to adjust the pH of phosphate-buffered saline (PBS) and other phosphate-based buffers.
  • Alkaline Lysis Buffer: Used in plasmid DNA extraction protocols to lyse bacterial cells and denature proteins.
2. Nucleic Acid Extraction and Denaturation
Sodium hydroxide plays a critical role in nucleic acid extraction and denaturation:
  • Plasmid DNA Extraction: In the alkaline lysis method, NaOH (in combination with sodium dodecyl sulfate, SDS) is used to lyse bacterial cells, denature proteins, and separate plasmid DNA from chromosomal DNA.
  • RNA Extraction: NaOH is used in some RNA extraction protocols to denature proteins and inactivate RNases.
  • DNA Denaturation: NaOH is used to denature double-stranded DNA into single-stranded DNA for applications such as Southern blotting and hybridization.
3. Gel Electrophoresis
Sodium hydroxide is used in the preparation and running of agarose and polyacrylamide gels:
  • Gel Preparation: NaOH is used to adjust the pH of gel buffers, such as TAE (Tris-acetate-EDTA) and TBE (Tris-borate-EDTA), to ensure optimal DNA migration.
  • Denaturing Gels: NaOH is used to prepare alkaline agarose gels for the separation of single-stranded DNA or RNA.
4. DNA and RNA Hydrolysis
Sodium hydroxide is used to hydrolyze nucleic acids for downstream applications:
  • RNA Hydrolysis: NaOH is used to hydrolyze RNA into nucleotides for quantitative analysis.
  • DNA Hydrolysis: NaOH can be used to hydrolyze DNA into smaller fragments for sequencing or other analytical techniques.
5. Protein Denaturation and Solubilization
Sodium hydroxide is used to denature and solubilize proteins:
  • Protein Extraction: NaOH is used to solubilize proteins from cell lysates or tissue samples.
  • Protein Denaturation: NaOH is used to denature proteins for SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) and Western blotting.
6. Sterilization and Cleaning
Sodium hydroxide is used for sterilization and cleaning of laboratory equipment:
  • Glassware Cleaning: NaOH solutions are used to clean and sterilize glassware by removing organic residues and contaminants.
  • Decontamination: NaOH is used to decontaminate surfaces and equipment by inactivating pathogens and degrading biological materials.
7. Cell Lysis
Sodium hydroxide is used to lyse cells for the extraction of intracellular components:
  • Bacterial Cell Lysis: NaOH is used in combination with SDS to lyse bacterial cells for plasmid DNA extraction.
  • Yeast Cell Lysis: NaOH is used to disrupt yeast cell walls for the extraction of proteins or nucleic acids.
8. DNA Sequencing
Sodium hydroxide is used in DNA sequencing protocols:
  • Template Denaturation: NaOH is used to denature double-stranded DNA templates into single-stranded DNA for sequencing reactions.
  • Capillary Cleaning: NaOH is used to clean and maintain capillary electrophoresis systems used in DNA sequencing.
9. Safety and Handling
  • Toxicity: Sodium hydroxide is highly corrosive and can cause severe burns to skin and eyes. It should be handled with care, using appropriate personal protective equipment (PPE) such as gloves, lab coats, and safety goggles.
  • Storage: Store NaOH in a cool, dry place in tightly sealed containers to prevent absorption of moisture and CO₂ from the air.
  • Disposal: Dispose of NaOH waste according to local regulations, neutralizing it with a weak acid (e.g., acetic acid) before disposal.
10. Advantages of Sodium Hydroxide
  • Strong Base: NaOH is a strong base, making it highly effective for pH adjustment and denaturation.
  • Cost-Effective: NaOH is inexpensive and readily available.
  • Versatility: It can be used in a wide range of molecular biology applications, from nucleic acid extraction to protein denaturation.
11. Limitations
  • Corrosiveness: NaOH is highly corrosive and can damage equipment and surfaces if not handled properly.
  • pH Instability: NaOH solutions can absorb CO₂ from the air, leading to a decrease in pH over time.

CHM.310465 - Sodium hydroxide - ACS reagent, ≥97.0% - CAS: 1310-73-2

SKU: CHM.310465
€18.00Price
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  • 1. General Information

    • Chemical Formula: NaOH

    • Molecular Weight: 40.00 g/mol

    • CAS Number: 1310-73-2

    • Grade: ACS Reagent

    • Purity: ≥97.0%

    2. Physical Properties

    • Appearance: White pellets, flakes, or granules.

    • Odor: Odorless.

    • Density: 2.13 g/cm³ (at 20°C).

    • Melting Point: 318°C (604°F).

    • Boiling Point: 1,388°C (2,530°F).

    • Solubility: Highly soluble in water (1,090 g/L at 20°C), ethanol, and glycerol. Insoluble in non-polar solvents like ether.

    • pH: Strongly alkaline (pH ~14 in 1 M aqueous solution).

    3. Chemical Properties

    • Hygroscopicity: Sodium hydroxide is highly hygroscopic, absorbing moisture and carbon dioxide (CO₂) from the air. This can lead to the formation of sodium carbonate (Na₂CO₃) on the surface of NaOH pellets or flakes.

    • Reactivity:

      • Reacts exothermically with water, releasing heat.

      • Reacts with acids to form salts and water (neutralization reaction).

      • Reacts with aluminum, zinc, and other amphoteric metals to produce hydrogen gas.

      • Reacts with CO₂ to form sodium carbonate.

    • Stability: Stable under normal conditions but may decompose at high temperatures (>800°C) to produce sodium oxide (Na₂O) and oxygen (O₂).

    4. Purity and Impurities

    • Purity: ≥97.0% NaOH.

    • Impurities:

      • Sodium Carbonate (Na₂CO₃): ≤1.0%.

      • Chloride (Cl⁻): ≤0.005%.

      • Sulfate (SO₄²⁻): ≤0.003%.

      • Heavy Metals (as Pb): ≤5 ppm.

      • Iron (Fe): ≤0.001%.

      • Potassium (K): ≤0.02%.

    5. Analytical Methods

    The purity and quality of sodium hydroxide can be assessed using:

    • Titration: Acid-base titration to determine NaOH concentration.

    • Ion Chromatography: To detect and quantify chloride, sulfate, and other anions.

    • Atomic Absorption Spectroscopy (AAS): To measure heavy metal impurities.

    • Loss on Drying (LOD): To determine moisture content.

    6. Storage and Handling

    • Storage Conditions: Store in a cool, dry place in tightly sealed containers to prevent absorption of moisture and CO₂.

    • Shelf Life: Indefinite if stored properly, but surface carbonation may occur over time.

    • Handling Precautions:

      • Use personal protective equipment (PPE), including gloves, lab coats, and safety goggles.

      • Handle in a well-ventilated area or fume hood to avoid inhalation of dust or aerosols.

      • Avoid contact with skin, eyes, and clothing, as NaOH is highly corrosive.

    7. Safety Information

    • Toxicity: Sodium hydroxide is highly corrosive and can cause severe burns to skin and eyes. Inhalation of dust or aerosols can cause respiratory irritation.

    • Flammability: Non-flammable, but reacts exothermically with water and acids, releasing heat.

    • Environmental Impact: Highly alkaline and can cause harm to aquatic life. Neutralize before disposal.

     

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