Introduction

Preservatives, sometimes called bacteriostats, are chemicals that inhibit the growth of microorganisms. The same substance exhibits a bacteriostatic effect at low concentrations and a bactericidal effect at higher concentrations. Many disinfecting and antiseptic drugs are often good preservatives in formulations.

Mechanism of Preservatives

1. Denaturing, precipitating, or coagulating the protein of pathogenic microorganisms, such as ethanol, benzyl alcohol, etc.

2. Combine with the enzyme system of pathogenic microorganisms, affect, or block its metabolic process, such as benzoic acid and hydroxybenzene esters, acting on the cell membrane of bacteria or competing for their coenzymes.

3. Reduce the surface tension, increase the permeability of the plasma membrane of the bacterial body, make the cell rupture, lysis, such as some cationic surfactants

Subtypes of Preservative Excipients

Parabens

Parabens, including methylparaben, ethylparaben, and propylparaben, are widely used as preservatives due to their antimicrobial properties. They exhibit a broad spectrum of activity against various microorganisms and are commonly used in liquid oral formulations, topical creams, and ophthalmic solutions.

Benzalkonium Chloride

Benzalkonium chloride is a quaternary ammonium compound that acts as a potent antimicrobial agent. It is effective against a wide range of pathogens and is commonly utilized in nasal sprays, eye drops, and ophthalmic ointments.

Benzyl Alcohol

Benzyl alcohol is widely used as a preservative in parenteral formulations, such as injectable solutions and multi-dose vials. It demonstrates antimicrobial activity against bacteria and fungi and is well-tolerated by most patients.

Phenol

Phenol is an antiseptic and preservative that exhibits both bactericidal and fungicidal properties. It is used in a variety of pharmaceutical products, including throat sprays, topical creams, and dermatological preparations.

Examples

Methylparaben

Methylparaben is a commonly employed paraben preservative excipient. It is widely used in oral liquids, creams, and lotions. Methylparaben offers excellent antimicrobial activity and is well-tolerated by patients.

Chlorobutanol

Chlorobutanol is another effective preservative that demonstrates broad-spectrum antimicrobial activity. It is commonly used in injectable solutions, eye drops, and nasal preparations.

Thimerosal

Thimerosal, a mercury-containing compound, is utilized as a preservative in vaccines, preventing bacterial and fungal contamination. It ensures the stability and sterility of the vaccine formulations.

Conclusion

Preservative excipients are crucial in maintaining patient safety and product integrity. They prevent the growth of microorganisms that may compromise the efficacy of pharmaceutical products and pose risks to patient health. Without proper preservation, products may become contaminated, reducing their shelf life and potentially causing adverse effects. Partnering with Protheragen-ING, a reputable supplier, ensures the availability of high-quality excipients and supports the development of stable and efficacious pharmaceutical products. If you have any excipient requirements, please contact us by phone or email, and we will respond within 2-4 working days.