Microbiological analyses sterilization

Compared with most analytical techniques, mass spectrometry is generally faster, providing both separation of complex mixtures and a fundamental measurement simultaneously. Due to this analytical speed, mass spectrometry is also amenable to high-throughput analysis of very many samples. Therefore, mass spectrometry represents an important approach for analysis of biological exposure [56]. In addition to clinical applications, diagnostics are also needed for food and water safety, bioreactor analysis/sterility assurance, and environmental microbiology. 

Whenever possible, samples for microbiological analysis (50 to 100 mL) should be removed asepticaUy and placed into sterile containers to reduce the potential for secondary contamination due to non-wine microorganisms. Samples can be removed through sampling ports on tanks or by wine thiefs/pipettes. Sampling devices should be sterilized either by flame or 70% v/v ethanol prior to use. If a steriliant is used, the thief or pipette should be rinsed with sterile water before obtaining the sample. 

A sterilization process may thus be developed without a full microbiological background to the product, instead being based on the ability to deal with a worst case condition. This is indeed the situation for official sterilization methods which must be capable of general application, and modem pharmacopoeial recommendations are derived firm a careful analysis of experimental data on bacterial spore survival following treatments with heat, ionizing radiation or gas. 

In the case of recombinant proteins intended for use in sterile pharmaceutical products, additional process controls on microbiologic aspects of analysis must be established and validated to ensure aseptic conditions throughout the manufacturing process. 

Other physical tests may allow routine in-place evaluation of the microbiological integrity of vials. Headspace gas analysis is one such method. Many sterile products are held under nitrogen or some other gas in vials. The gas content of the headspace should, with a perfect seal, remain constant over time rather than becoming equilibrated with the atmosphere under a less than perfect seal. This type of analysis is amenable to chemical methodology and is likely done routinely in pharmaceutical production for reasons other than evaluation of microbiological integrity. 

The sampling procedure used will obviously depend on the type of sample whether it is liquid or solid fresh, chilled or frozen and the type of container e.g. tinned, bottled). Other major problems are the frequency of sampling and the position on a production line from which a sample is taken. For example, when sampling from a food production line is carried out, an important consideration is whether or not the food has been subjected to sterilisation, or any form of pasteurisation after the point from which the sample was taken. This is considered further in the chapter on food microbiology under the concept of Hazard Analysis Critical Control Point (HACCP). Whatever the form of the sample, it should be collected in a sterile container using aseptic techniques, returned to the laboratory under conditions identical to those from which it was taken, and processed as rapidly as possible. 

Finished parenteral products prepared in the radiopharmacy department must be sterile. Based on a risk analysis one may conclude that the risk of non-sterility is very low for standard radiopharmaceutical kit preparations. The risk of contamination is somewhat higher for the eluate from radionuclide generators, especially when they are used for a long period. The injection bottle on top of a Tc generator (sterile sodium chloride solution for injection) is changed asepti-cally each day however, the inside of the generator system is not sterilised nor disinfected. For that reason it is recommended to control the microbiological quality of the... 

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