In this article we will discuss about the characteristics and factors influencing antimicrobial agent.
Characteristics of Antimicrobial Agent:
1. The capacity of the substance to kill or inhibit microorganisms is the first requirement. The chemical should possess a broad spectrum of antimicrobial activity at a low concentration.
2. The chemical substance must be soluble in water or other solvents to the extent necessary for effective use.
3. The substance should be stable. Changes in the substance upon standing should be minimal and should not result in significant loss of germicidal action.
4. The compound should be ideally lethal to microorganisms and non-injurious to humans and other animals, i.e., it should be nontoxic to humans and other animals.
5. While using the compound, it should not be necessary to raise the temperature beyond that normally found in the environment where it is to be used. It is important because, for convenience, a chemical reaction occurring at 37°C (body temp.) may not take place at 25°C (room temp.).
6. Unless the substance can penetrate through surfaces, its germicidal action is limited solely to the site of application. Sometimes, of course, surface action is all that is required.
7. The preparation of the chemical substance must be uniform in composition so that active ingredients are present in each application. Pure chemicals are uniform, but mixtures of materials may lack homogeneity.
8. Many chemical agents show great the affinity for proteins or other organic material. When such disinfectants are used in situations where there is considerable organic material besides that of the microbial cells, little, if any, of the disinfectant will be available for action against the microorganisms.
9. A disinfectant which is also a detergent (cleaning agent) accomplishes two objectives, and the cleansing action improves the effectiveness of the disinfectant.
10. It should not rust or otherwise disfigure metals nor stain or damage fabrics.
11. The compound must be available in large quantities at a reasonable price.
12. The substance should possess deodourizing ability because this ability is a desirable attribute. Ideally the disinfectant itself should either be odourless or possess a pleasant smell.
Factors Influencing Antimicrobial Agent:
During selecting the most appropriate antimicrobial agent to be used for a particular practical application, certain factors are required to be assessed.
The main of such factors are the following:
1. A chemical agent used to disinfect contaminated inanimate objects might be quite harmless to the skin; i.e., it might not do serious injury to the issue cells.
2. The substance selected must be compatible with the material to which it is applied.
3. Chemical agents are not all equally effective against microorganisms like bacteria, fungi, viruses, etc. For example, gram-positive and gram-negative bacteria show differences when subjected to the same chemical agent; Escherichia coli is much more resistant to cationic disinfectants than Staphylococcus aureus. Differences in action of the chemical agent also exist between strains of the same species. Therefore, the agent selected must be known to be effective against the type of microorganism that needs to be destroyed.
4. The factors discussed such as temperature pH, time, concentration, and presence of extraneous organic material, may all have a bearing on the rate and efficiency of antimicrobial action. The successful use of an antimicrobial agent needs clear understanding of the influence of these conditions on the particular agent, so it can be employed under the most favourable conditions.