1. Product Overview
Phosphomolybdic Acid, CAS 7365-82-4, also known as 12-Molybdophosphoric Acid or PMA, is a heteropoly acid usually supplied as a yellow to yellowish green crystalline hydrate H3PMo12O40 dot nH2O with n around 12 to 14. It is highly soluble in water and many polar organic solvents giving a colorless to pale yellow acidic solution pH about 1 to 2 at 10 percent w/v. This reagent grade AR and Biological Stain grade material is widely used in histology as a counterstain in PTAH Masson Trichrome and van Gieson protocols as well as a negative stain in electron microscopy. It also serves as a strong oxidizing agent and acid catalyst in organic synthesis. Each batch is tested for solubility clarity absence of precipitated molybdate and staining performance.
2. Key Features & Advantages
• Strong heteropoly acid with dual acid and oxidizing properties suitable for catalysis and selective oxidations.
• Extremely high water solubility over 100 gram per 100 milliliter forming clear colorless to pale yellow solution ideal for staining and precipitation.
• Excellent counterstain performance in PTAH Masson and van Gieson giving sharp contrast between collagen cytoplasm and muscle fibers.
• Forms insoluble complexes with alkaloids proteins and certain lipids enabling TLC visualization and protein precipitation.
• Stable as dry crystalline hydrate when stored cool dark and dry; solutions should be prepared fresh to avoid reduction to molybdophosphoric blue.
• Available in AR Analytical Reagent BS Biological Stain and high purity grades for research and industrial catalysis.
3. Main Applications
• Histology and cytology: core reagent in Phosphomolybdic Acid Hematoxylin PTAH stain for mitochondria fibrils and glial fibers; counterstain in Masson Trichrome and van Gieson to stain collagen pink red cytoplasm yellow and muscle red; also used in phosphotungstic acid hematoxylin combinations.
• Electron microscopy: negative staining agent for viruses nanoparticles and macromolecular complexes due to high electron density and amorphous film formation.
• Thin layer chromatography: universal spraying reagent for visualizing alkaloids steroids lipids amino acids and other organic compounds which turn blue green upon heating.
• Organic synthesis and catalysis: acid catalyst and selective oxidant for alkene epoxidation alcohol oxidation and dehydration reactions; used in heterogeneous and homogeneous catalytic systems.
• Biochemistry: protein precipitating agent for separating globulins from albumins; also applied in tungsten molybdenum separation by selective precipitation.
• For research use only not for therapeutic or diagnostic use in humans or animals.
4. Technical Specifications
5. Storage & Handling
• Packaging: laboratory 1 g 5 g 25 g 100 g in amber glass vials with PTFE lined caps to block light and moisture; bulk 500 g 1 kg in double sealed polyethylene bags within moisture barrier foil pouches or brown bottles; industrial 25 kg cardboard drum with inner PE liner; working solutions prepared fresh in deionized water stored in amber bottles refrigerated 2 to 8 C and used within 24 to 48 hours before turning blue from reduction.
• Storage Conditions: store solid in a cool dry dark place 2 to 25 C preferably in a desiccator away from direct light heat strong bases reducing agents and combustible organics; highly hygroscopic so keep container tightly sealed after each use.
• Shelf Life: 24 months unopened original packaging; opened vials use within 3 to 6 months and reseal immediately.
• Handling: use in well ventilated area or fume hood; avoid dust inhalation; wear nitrile gloves safety goggles and lab coat; do not mix solid or concentrated solution with reducing agents alkalis or organics which may cause exothermic reaction or reduction to heteropoly blue.
6. Safety Overview
• GHS Classification: Warning GHS07; Acute Tox 4 Oral; Skin Corr 1B; Eye Dam 1; Oxidizing Solid 2; STOT SE 3 Respiratory irritation.
• Hazard Statements: H272 May intensify fire; H302 Harmful if swallowed; H314 Causes severe skin burns and eye damage; H335 May cause respiratory irritation.
• Protective Measures: wear nitrile gloves face shield or safety goggles and a lab coat; use local exhaust ventilation; keep away from combustibles reducing agents and bases.
• First Aid: Inhalation move to fresh air seek medical help if irritation or breathing difficulty; Eye Contact rinse immediately with plenty running water min 15 minutes remove contact lenses get urgent medical care for corneal damage; Skin Contact rinse thoroughly with water min 15 minutes remove contaminated clothing launder before reuse seek medical attention for burns; Ingestion rinse mouth do NOT induce vomiting drink small amount water or milk seek immediate medical advice corrosive and harmful.
• Environmental Precautions: contains molybdenum and phosphate may be toxic to aquatic life at high concentration; prevent release into drains waterways; collect spilled solid or blue solution as hazardous chemical waste per local regs; classified as oxidizing solid UN 3087 Class 5.1 PG II for transport.
