Antimicrobials: Mechanism, Classification, Potassium permanganate, Boric acid, Hydrogen peroxide, Chlorinated lime, Iodine and its preparations : Pharmaguideline -->

Editable Pharmaceutical Documents in MS-Word Format


Antimicrobials: Mechanism, Classification, Potassium permanganate, Boric acid, Hydrogen peroxide, Chlorinated lime, Iodine and its preparations

An antimicrobial is a chemical that is added to a product to kill or inhibit microbes. Antibacterial and biocides are also called antimicrobials.


An antimicrobial is a chemical that is added to a product to kill or inhibit microbes. Antibacterial and biocides are also called antimicrobials. Several antimicrobials need to be carefully screened, including halogenated aromatic compounds like triclosan and triclocarban, nanosilver, and quaternary ammonium salts like benzalkonium chloride.


As bacteria develop resistance to antimicrobial agents, treating bacterial infections becomes more difficult. It is common for antimicrobial agents to be classified based on their main mechanisms of action.

At the cellular level, antimicrobials prevent microorganisms from growing and disrupting their activities. Mostly, antimicrobial products protect everyday things like surface coating, toys, hospital equipment, textiles, etc. By creating an inhospitable environment for micro-organisms like bacteria. Mildew and Mold. To reduce the damage as well as the shelf life of the microbes, antimicrobials work in a way through which the growth of the micro-organisms is inhibited in larger amounts and hence protects the products against the effects of these microbes. Mostly the products are all guaranteed to remain fresh and clean for a longer period because it has an integrated antimicrobial solution into the product that disrupts the environment for the microbes for growing uncontrollably.


Antimicrobial agents are classified into various types such as,
  • Four-quinolones - DNA synthesis inhibitors
  • Tetracyclines, macrolides, and aminoglycoside antibiotics are all chemical inhibitors of protein synthesis
  • The rifampicin is an inhibitor of RNA synthesis
  • Vancomycin, beta-lactam and Fosfomycin inhibit bacterial cell wall formation
Furthermore, they are classified by,
  • Chemical structure
  • Antimycobacterial agents
  • Sources
  • Mechanism of action
  • Type of action
  • Spectrum of activity
  • Organisms affected
  • Therapeutic use

Potassium permanganate

Although potassium permanganate has extensive antibacterial effects, it has the drawback of staining tissues and clothes brown due to its vivid purple hue in the solution. For disinfection, it is an efficient algicide (0.01 percent) and virucide (1 percent), however quantities greater than 1:10,000 irritate tissues. Old solutions turn a dark brown color and lose their effectiveness.

Boric acid

This white compound is water-soluble and naturally occurs. The composition of the compound includes oxygen, boron, and hydrogen. The chemical is believed to be antimicrobial and antifungal. The substance can be irritating and result in severe reactions.

Uses - Homeopathic medicines are often formulated with boric acid as a component. A small amount of boric acid, friendly bacteria, and vitamin E are present in this medicine. Diaper rash, insect bites, and sunburn are usually treated with dilute solutions of zinc oxide. Rats, cockroaches, and flies can all benefit from the use of boric acid. Because it has proven highly beneficial for maintaining swimming pools, boric acid is known as a swimming pool chemical. In addition to preventing algae growth, it helps maintain the pH levels of pool water. There is less chlorine required in the swimming pool due to this product. Clear, sparkling water is maintained by utilizing the product. Fungi are also removed from the pool water by using the compound.

Hydrogen peroxide

The oxygen is released by 3% hydrogen peroxide solution when it comes in contact with catalase, which is present on mucous membranes and wound surfaces. A standard volume of 3% hydrogen peroxide releases about 10 milliliters of oxygen at standard pressure and temperature. In addition to removing pus from wounds, effervescent action also serves to eliminate infection by cleaning and deodorizing infected tissue. The antimicrobial effect of this substance is limited to the superficial layers of the applied surface and lasts only for a short period since tissue penetration is not possible. As a result of the dissection of gas under pressure into tissues, hydrogen peroxide may result in oxygen embolism, particularly in partially closed spaces, such as operative wounds. Hydrogen peroxide finds increased use as a disinfectant in food and water preparation facilities as well as to sterilize dental and surgical instruments, despite its limited effectiveness as an antiseptic.

Chlorinated lime

In bleaching or disinfection, chlorinated lime powder is used. People can become poisoned by chlorinated lime if they swallow it. It has a melting point of 100° C. Exposure to air causes it to become moist and decompose rapidly, releasing hypochlorous acid.

Uses -

The rapid bactericidal action of calcium hypochlorite can be expected. Many types of bacteria, some fungi, algae, viruses, yeast, protozoa, and some types of bacteria are killed by it. The disinfecting agent calcium hypochlorite is commonly used in swimming pools and drinking water in public places. In addition to disinfecting surfaces and equipment in kitchens, calcium hypochlorite is also used. Others are bathroom cleaners, household disinfectants, algaecide, laundry detergents, herbicides, and pesticides.

Organic chemistry
Calcium hypochlorite has some applications in organic chemistry because it is an excellent oxidizing agent. To create fragmented carboxylic acids or aldehydes, the compound can be used to break down glycols, α-hydroxycarboxylic acids, and keto acids. Halo form reactions can also be carried out using calcium hypochlorite to manufacture chloroform.


An effective germicide, elemental iodine has a wide range of activity and low tissue toxicity. Bacteria will be killed in 1 minute and spores in 15 minutes by a solution containing 50 parts per million iodine. Water is not readily soluble in this agent, and ethanol is readily soluble, enhancing its antibacterial effects. The tincture of iodine and sodium iodide (NaI) contains 2% iodine and 2.4% sodium iodide (NaI) dissolved in 50% ethanol, which is used to disinfect the skin. The iodine tincture we used contained 7% iodine and 5% potassium iodide (KI), dissolved in 95% ethanol, thus being more potent but also more irritating than regular iodine tinctures. It is used as a non-irritant antiseptic on burns and wounds. It contains two parts of iodine and two parts of sodium iodide dissolved in water. Lugol's strong iodine solution (5% iodine and 10% potassium iodide.) contains these components in an aqueous solution.

Iodophors consist of Iodine and a carrier (e.g., povidone-Iodine, poloxamer-Iodine), and are water-soluble and more stable than older formulations. These products are widely used as skin disinfectants, including before surgery, as they slowly release iodine as an antimicrobial agent. There is no stinging or staining. The iodophors do not damage tissues, although repeated exposure to them can cause contact dermatitis. However, they can corrode metals. Bacteria, viruses, and fungi are all killed by them, but spores are less effective. Despite the presence of organic matter, iodophor solutions remain antibacterial even at pH 4. When this activity is lost, the solution often turns green. Acidic media are frequently maintained by mixing phosphoric acid with iodophors. Among the uses of these substances are to control mastitis in teat dips, sanitize dairy products, and as antiseptic or disinfectants for various dermal and mucosal infections.

To protect you from the hazards of phosphoric acid and iodine, you should wear protective goggles and latex gloves.
  • The ring, a gauze pad, and a stand should be set up inside a hood. A 100 mL beaker, a watch glass, a stirring rod, a Bunsen burner, and a striking device are also needed. When the burner is mounted on the stand, the ring should be about 2 inches (2 cm) above the top.
  • After weighing the potassium iodide, add between 0.9g and 1.1g.
  • You will weigh 0.5 g to 0.7 g of manganese (IV) oxide in a second weighing boat after zeroing the balance.
  • The solid chemicals must be stirred for a few seconds after they have been added to a 100-mL beaker of potassium iodide and manganese (IV) oxide.
  • Pour 1 mL of concentrated phosphoric acid into a graduated cylinder containing 10 mL of phosphoric acid. Pour the phosphoric acid carefully into the beaker containing the chemicals, allowing the acid to drain through the beaker for 15 seconds until all acid has disappeared from the sides of the graduated cylindrical vessel. To prevent acid from splashing into your face, it is necessary to rinse out the graduated cylinder several times using a slow stream of water.
  • Assemble the ring stand by placing the beaker on the gauze pad, placing a watch glass over the beaker, and placing an ice cube over the watch glass.
  • A light should be placed directly under the beaker when lighting the burner. The flame should be low in heat, i.e., there should be a bushy, small flame, and the air vent should be closed. Note any reactions that occur. Once the beaker's purple gas has significantly decreased, turn off the Bunsen burner.
  • Once the beaker and watch glass have been turned off, they need to cool for 5 minutes.
  • Afterward, carefully remove the ice cube from the watch glass, pour off any liquid that has built up in it, and look at the crystals that have formed on the underside of the glass.
Get subject wise printable pdf documentsView Here

Ankur Choudhary is India's first professional pharmaceutical blogger, author and founder of, a widely-read pharmaceutical blog since 2008. Sign-up for the free email updates for your daily dose of pharmaceutical tips.
.moc.enilediugamrahp@ofni :liamENeed Help: Ask Question

No comments: Read Comment Policy ▼

Post a Comment

Please don't spam. Comments having links would not be published.

Popular Categories

QA SOPs QC SOPs Micro SOPs HVAC Production SOPs Stores SOPs Checklists Maintenance SOPs HPLC Sterile GLP Validation Protocols Water System GDP Regulatory Maintenance Calibration Warning Letters Education B.Pharmacy
Resume Pro


Show All ❭❭Jobs by PharmaJobs

Follow Pharmaguideline



Editable Pharmaceutical Documents in MS-Word Format. Ready to use SOPs, Protocols, Master Plans, Manuals and more...




Pharmaceutical Updates

✔ Worldwide Regulatory Updates
✔ Pharmaceutical News Updates
✔ Interview Questions and Answers
✔ All Guidelines in One Place


Recent Posts