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Importance of a Microbiological Evaluation Program for Controlled Environments
Monitoring of total particulate count in controlled environments, even with the use of electronic instrumentation on a continuous basis, does not provide information on the microbiological content of the environment. The basic limitation of particulate counters is that they measure particles of 0.5 µm or larger. While airborne microorganisms are not free-floating or single cells, they frequently associate with particles of 10 to 20 µm. Particulate counts as well as microbial counts within controlled environments vary with the sampling location and the activities being conducted during sampling. Monitoring the environment for nonviable particulates and microorganisms is an important control function because they both are important in achieving product compendial requirements for Particulate Matter and Sterility under Injections 1.
Microbial monitoring programs for controlled environments should assess the effectiveness of cleaning and sanitization practices by and of personnel that could have an impact on the bioburden of the controlled environment. Microbial monitoring, regardless of how sophisticated the system may be, will not and need not identify and quantitate all microbial contaminants present in these controlled environments. However, routine microbial monitoring should provide sufficient information to ascertain that the controlled environment is operating within an adequate state of control.
Environmental microbial monitoring and analysis of data by qualified personnel will permit the status of control to be maintained in clean rooms and other controlled environments. The environment should be sampled during normal operations to allow for the collection of meaningful data. Microbial sampling should occur when materials are in the area, processing activities are ongoing, and a full complement of operating personnel is on site.
Microbial monitoring of clean rooms and some other controlled environments, when appropriate, should include quantitation of the microbial content of room air, compressor air that enters the critical area, surfaces, equipment, sanitization containers, floors, walls, and personnel garments (e.g., gowns and gloves). The objective of the microbial monitoring program is to obtain representative estimates of bioburden of the environment. When data are compiled and analyzed, any trends should be evaluated by trained personnel. While it is important to review environmental results on the basis of recommended and specified frequency, it is also critical to review results over extended periods to determine whether trends are present. Trends can be visualized through the construction of statistical control charts that include alert and action levels. The microbial control of controlled environments can be assessed, in part, on the basis of these trend data. Periodic reports or summaries should be issued to alert the responsible manager.
When the specified microbial level of a controlled environment is exceeded, a documentation review and investigation should occur. There may be differences in the details of the investigation, depending on the type and processing of the product manufactured in the room. Investigation should include a review of area maintenance documentation; sanitization documentation; the inherent physical or operational parameters, such as changes in environmental temperature and relative humidity; and the training status of personnel involved. Following the investigation, actions taken may include reinforcement of training of personnel to emphasize the microbial control of the environment; additional sampling at increased frequency; additional sanitization; additional product testing; identification of the microbial contaminant and its possible source; and an evaluation of the need to reassess the current standard operating procedures and to revalidate them, if necessary.
Based on the review of the investigation and testing results, the significance of the microbial level being exceeded and the acceptability of the operations or products processed under that condition may be ascertained. Any investigation and the rationale for the course of action should be documented and included as part of the overall quality management system.
A controlled environment such as a clean zone or clean room is defined by certification according to a relevant clean room operational standard. Parameters that are evaluated include filter integrity, air velocity, air patterns, air changes, and pressure differentials. These parameters can affect the microbiological bioburden of the clean room operation. The design, construction, and operation of clean rooms varies greatly, making it difficult to generalize requirements for these parameters. An example of a method for conducting a particulate challenge test to the system by increasing the ambient particle concentration in the vicinity of critical work areas and equipment has been developed by Ljungquist and Reinmuller.1 First, smoke generation allows the air movements to be visualized throughout a clean room or a controlled environment. The presence of vortices or turbulent zones can be visualized, and the airflow pattern may be fine-tuned to eliminate or minimize undesirable effects. Then, particulate matter is generated close to the critical zone and sterile field. This evaluation is done under simulated production conditions, but with equipment and personnel in place.
Proper testing and optimization of the physical characteristics of the clean room or controlled environment is essential prior to completion of the validation of the microbiological monitoring program. Assurance that the controlled environment is operating adequately and according to its engineering specifications will give a higher assurance that the bioburden of the environment will be appropriate for aseptic processing. These tests should be repeated during routine certification of the clean room or controlled environment and whenever changes made to the operation, such as personnel flow, processing, operation, material flow, air-handling systems, or equipment layout, are determined to be significant.
Training of Personnel
Aseptically processed products require manufacturers to pay close attention to detail and to maintain rigorous discipline and strict supervision of personnel in order to maintain the level of environmental quality appropriate for the sterility assurance of the final product.
Training of all personnel working in controlled environments is critical. This training is equally important for personnel responsible for the microbial monitoring program, where contamination of the clean working area could inadvertently occur during microbial sampling. In highly automated operations, the monitoring personnel may be the employees who have the most direct contact with the critical zones within the processing area. Monitoring of personnel should be conducted before or after working in the processing area.
Microbiological sampling has the potential to contribute to microbial contamination due to inappropriate sampling techniques. A formal personnel training program is required to minimize this risk. This formal training should be documented for all personnel entering controlled environments.
Management of the facility must assure that all personnel involved in operations in clean rooms and controlled environments are well versed in relevant microbiological principles. The training should include instruction on the basic principles of aseptic processing and the relationship of manufacturing and handling procedures to potential sources of product contamination. This training should include instruction on the basic principles of microbiology, microbial physiology, disinfection and sanitation, media selection and preparation, taxonomy, and sterilization as required by the nature of personnel involvement in aseptic processing. Personnel involved in microbial identification will require specialized training on required laboratory methods. Additional training on the management of the environmental data collected must be provided to personnel. Knowledge and understanding of applicable standard operating procedures is critical, especially those standard operating procedures relating to corrective measures that are taken when environmental conditions so dictate. Understanding of regulatory compliance policies and each individual's responsibilities with respect to good manufacturing practices (GMPs) should be an integral part of the training program as well as training in conducting investigations and in analyzing data.
The major source of microbial contamination of controlled environments is the personnel. Contamination can occur from the spreading of microorganisms by individuals, particularly those with active infections. Only healthy individuals should be permitted access to controlled environments. |
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进行过促生长检验的通用丰富培养基，可以被应用。来自将要进行无菌操作生产的控制环境中的隔离群也可以被应用。培养基的无菌操作之后，填充容器被置于22.5 ± 2.5 或32.5 ± 2.5 进行孵育。所以填充培养基的容器至少应当孵育14天。如果培养基样品的孵育温度有两个，那么这些填充容器在每个温度下至少要孵育7天。孵育过后，应当对培养基填充容器进行生长检查。培养基填充隔离群以属进行鉴别，如果出于调查污染源为目的的需要，可能的话要鉴别到种。
一志愿大连理工大学材料求调剂
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