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CHM.219001 - Potassium Phosohate Dibasic - ACS Reagent ≥98% - CAS: 7758-11-4
Potassium phosphate dibasic (K₂HPO₄), with the Chemical Abstracts Service (CAS) number 7758-11-4, is a widely used chemical in molecular biology due to its role as a buffering agent and source of phosphate ions. It is an inorganic salt that provides stability to biological systems and is essential for various laboratory protocols. Below is a detailed overview of the molecular biology applications of potassium phosphate dibasic:
1. Buffer Preparation
Potassium phosphate dibasic is a key component of phosphate buffers, which are widely used in molecular biology to maintain stable pH conditions. Examples include:
  • Phosphate-Buffered Saline (PBS): A common buffer used for cell washing, immunohistochemistry, and immunofluorescence assays. PBS typically contains potassium phosphate dibasic along with sodium chloride and potassium chloride.
  • Lysis Buffers: Used for cell lysis and protein extraction, where maintaining a stable pH is critical for preserving protein integrity.
  • Enzyme Assays: Potassium phosphate buffers are used in enzymatic reactions to maintain optimal pH and ionic strength.
2. Cell Culture Media
Potassium phosphate dibasic is used in cell culture media formulations to provide phosphate ions, which are essential for cell growth and metabolism. It helps:
  • Maintain Osmotic Balance: By contributing to the ionic strength of the medium.
  • Support Nutrient Uptake: Phosphate ions are required for the synthesis of nucleic acids, ATP, and other cellular components.
3. Nucleic Acid Extraction and Purification
Potassium phosphate dibasic is used in nucleic acid extraction protocols to stabilize pH and provide phosphate ions. Applications include:
  • DNA Extraction: Used in lysis buffers to maintain pH and ionic strength during cell lysis and DNA precipitation.
  • RNA Extraction: Helps stabilize RNA during isolation and purification steps.
4. Protein Crystallization
Potassium phosphate dibasic is used in protein crystallization screens to create conditions that promote the formation of protein crystals. It helps:
  • Stabilize Protein Structure: By providing a buffered environment.
  • Promote Crystal Growth: By optimizing ionic strength and pH.
5. Electrophoresis
Potassium phosphate dibasic is used in the preparation of electrophoresis buffers for the separation of nucleic acids and proteins. Examples include:
  • Agarose Gel Electrophoresis: Used in the running buffer to maintain pH and ionic strength.
  • Polyacrylamide Gel Electrophoresis (PAGE): Used in the preparation of gel buffers for protein separation.
6. Enzyme Reactions
Potassium phosphate dibasic is used in enzymatic reactions to provide a stable pH environment and phosphate ions, which are often required as cofactors or substrates. Examples include:
  • Kinase Assays: Phosphate ions are essential for kinase activity.
  • Phosphatase Assays: Used to study the activity of phosphatases, which remove phosphate groups from substrates.
7. Molecular Cloning
Potassium phosphate dibasic is used in molecular cloning protocols to stabilize pH and provide phosphate ions. Applications include:
  • Transformation Buffers: Used to prepare competent cells for DNA uptake.
  • Ligation Reactions: Helps maintain optimal conditions for DNA ligase activity.
8. Safety and Handling
  • Toxicity: Potassium phosphate dibasic is generally considered low toxicity, but it should be handled with care to avoid inhalation or contact with skin and eyes.
  • Storage: Store in a cool, dry place in tightly sealed containers to prevent moisture absorption.
  • Disposal: Dispose of according to local regulations for chemical waste.
9. Advantages of Potassium Phosphate Dibasic
  • Buffering Capacity: Effective at maintaining pH in the physiological range (pH 6.5–7.5).
  • Compatibility: Compatible with proteins, nucleic acids, and enzymes.
  • Cost-Effective: Inexpensive and widely available.
10. Limitations
  • Precipitation: Can form insoluble precipitates with divalent cations (e.g., Ca²⁺, Mg²⁺) at high concentrations.
  • pH Sensitivity: Buffering capacity is limited to the pH range of 6.5–7.5.
 

CHM.219001 - Potassium Phosohate Dibasic - ACS Reagent ≥98% - CAS: 7758-11-4

SKU: CHM.219001
€30.00Price
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Will ship from Malta 7-14 days.

  • 1. General Information

    • Chemical Formula: K₂HPO₄

    • Molecular Weight: 174.18 g/mol

    • CAS Number: 7758-11-4

    • Grade: ACS Reagent

    • Purity: ≥98%

    2. Physical Properties

    • Appearance: White crystalline powder or granules.

    • Odor: Odorless.

    • Density: 2.44 g/cm³ (at 20°C).

    • Melting Point: >465°C (decomposes).

    • Solubility: Highly soluble in water (1,500 g/L at 20°C). Insoluble in ethanol and other organic solvents.

    • pH: Alkaline (pH ~9.0–9.5 in 1% aqueous solution).

    3. Chemical Properties

    • Hygroscopicity: Potassium phosphate dibasic is mildly hygroscopic, absorbing moisture from the air under high humidity conditions.

    • Reactivity:

      • Reacts with strong acids to form monobasic potassium phosphate (KH₂PO₄) and phosphoric acid (H₃PO₄).

      • Reacts with strong bases to form tribasic potassium phosphate (K₃PO₄).

      • Forms insoluble precipitates with divalent cations (e.g., Ca²⁺, Mg²⁺) at high concentrations.

    • Stability: Stable under normal conditions but may decompose at high temperatures (>465°C) to produce potassium pyrophosphate (K₄P₂O₇) and water (H₂O).

    4. Purity and Impurities

    • Purity: ≥98% K₂HPO₄.

    • Impurities:

      • Loss on Drying: ≤0.2% (indicating moisture content).

      • Insoluble Matter: ≤0.01%.

      • Chloride (Cl⁻): ≤0.003%.

      • Sulfate (SO₄²⁻): ≤0.005%.

      • Heavy Metals (as Pb): ≤5 ppm.

      • Iron (Fe): ≤0.001%.

      • Sodium (Na): ≤0.02%.

    5. Analytical Methods

    The purity and quality of potassium phosphate dibasic can be assessed using:

    • Titration: Acid-base titration to determine phosphate content.

    • 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.

    • Shelf Life: Indefinite if stored properly.

    • Handling Precautions:

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

      • Avoid inhalation of dust and contact with skin and eyes.

    7. Safety Information

    • Toxicity: Potassium phosphate dibasic is generally considered low toxicity, but it may cause irritation to the skin, eyes, and respiratory tract.

    • Flammability: Non-flammable.

    • Environmental Impact: Generally considered environmentally benign, but high concentrations in water bodies can lead to eutrophication.

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