microbiology tests
 Pharmacopeial Sterility
Ethox STS can perform a variety of sterility assessments, following USP, JP, EP or other guidelines. We offer product immersion, membrane filtration and biological indicator transfer evaluation. Procedures must be validated through the Bacteriostasis/Fungistasis test described below.
Bacteriostasis/Fungistasis
In this test, low numbers of microorganisms are added to a media volume containing the test material to confirm that the test material does not interfere with the organisms’ growth.
Preservative Efficacy (USP <51>)
The USP defines four product categories, and directs that five challenge organisms be tested at defined intervals to demonstrate preservative effectiveness. Additional organisms may be selected.
Bioburden Determination
Ethox STS follows the bioburden procedure described in ANSI/ISO/AAMI 11737-1 1995. Following extraction, aliquots are plated to determine the number of mesophilic aerobes, fungi and bacterial spores. Incubation under anaerobic conditions is available on request.
Complete Contact Lens Microbiology
This battery of tests is defined in the FDA 510(k) guidance for industry document for contact lenses of May 1, 1997.
Including:
- Preservative Efficacy test similar to that described above, but with the addition of a 14-day rechallenge.
- Stand-alone Procedure for Disinfecting Products. Five challenge organisms are tested for survival at predetermined fractions of the product’s minimum recommended disinfection time.
- Regimen Testing. Disinfection efficacy is assessed by challenging the various stages of the manufacturer’s cleaning, rinsing and disinfection regimen with five organisms.
Biological Indicator Reduced Incubation Time
Performed according to the FDA guidelines for validation of Biological Indicator incubation time. This procedure permits establishment of a reduced incubation period to permit earlier release of sterile product, based on the use of Biological Indicators.
Environmental Testing (viable and non-viable)
Ethox STS will assist in the evaluation of the microbiological levels and of the nonviable contamination levels of your facility. This service is designed on an individual basis to meet the specific needs of each client. We can supply personnel and materials to perform the monitoring or just supply materials, and culture and enumerate bacterial plates that are returned to us by courier.
Microbial Limits Testing (USP <61>)
This test is designed to demonstrate that the viable aerobic microorganisms present in your product are free of the four pathogenic microbial species specified in the USP.
Antibiotic Potency (Zone of Inhibition—USP <81>)
This is a microbiological means of determining quantitatively the activity of antibiotics. The test sample’s activity is compared directly to that of a known reference standard by measuring the diameter of zones surrounding the samples in which bacterial growth is inhibited.
Package/Container Integrity Microbiology
- Sterility testing—uses the USP 40-item product immersion procedure described above under Pharmacopeial Sterility
- Microbial aerosol challenge as recommended in ISO 11607
- Seal leak test by dye penetration—ASTM F 1929. Aqueous dye is injected into the package near the seal and integrity of the seal is assessed visually.
- Package Burst Testing—air is injected into the sealed package and the pressure at which a seal fails is recorded. A modification of this procedure is called Creep to Burst Testing; in this test the package is pressurized to 80% of its theoretical burst value and held for a defined period of time. It is then further pressurized until it bursts and the final burst pressure is recorded.
- Vial Test
D Value Determination—measures the resistance of microorganisms to steam, EO or other sterilization conditions by determining the length of exposure time required to reduce the surviving population by 90%. Survivor curve or fraction-negative techniques may be utilized.
D Value Determination—Pharmaceuticals
Measurement of D Values in the presence of pharmaceutical products. This often requires the use of membrane filtration methods.
z Value Determination
z values are measured at a variety of temperatures to determine the change in D value as a function of temperature. z value is the temperature increase required to reduce the thermal death time by a factor of 10.
Biological Indicator Survival/Kill Time Determination
The resistance of Biological Indicators to various sterilants is measured as described in individual USP monograph for Biological Indicators.
Accelerated/Real-time Aging Incubation and Testing
Packaged products are exposed to extreme conditions of temperature and humidity—the performance of the product and/or packaging is evaluated. Using specialized exposure chambers, STS can expose products to the chosen accelerated aging conditions and at the conclusion of the exposure period evaluate the packaging and in the case of pharmaceutical products, perform stability indicating analyses of the active ingredients. Products that complete this exposure with no damage can be labeled with extended expiration dates, as described in ISO 11607 and AAMI TIR No. 17--1997.
To learn more call Gary Chilson at 1.800.836.4850 or e-mail us!
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