Aseptic rooms

Regardless of the methods used to obtain a clean air environment, unless the parenteral operator is made completely aware of the limits of laminar flow, uses careful, planned movements, and is wearing proper clothing, he or she can be a source of product contamination. Operator movement within aseptic rooms should be minimized. The rooms must be disinfected regularly and thoroughly before setting up for aseptic operation. 

The last two methods are not generally applicable to the small laboratory except insofar as low pressure mercury vapour lamps emitting light of 254 nm may be used to sterilise the air in aseptic rooms and cabinets (see 9.4.1). 

When an aseptic room is not in use the air may be sterilised by use of UV germicidal lamps. These should be installed in a position such that the whole room is illuminated and should be sufficiently powerful to be effective at the extreme comers of the room. 

Horizontal-flow cabinets are satisfactory for aseptic manipulations such as media preparation where potentially hazardous aerosols are not generated. In these the filtered air enters through the back of the cabinet and leaves through the front. A horizontal-flow cabinet is a miniaseptic room which is much easier and cheaper to maintain than a walk-in aseptic room. In addition, it has the advantage that the worker is not confined within a small room which may become extremely hot and stuffy and, secondly, that the worker s head is separated from the cultures by a perspex screen thus further reducing the chance of contamination. 

Activities in clean and aseptic rooms should be kept to a minimum, and movements of personnel should be controlled and methodical, to avoid excessive shedding of particles and organisms due to over vigorous activity. 

B. The aseptic room in A shall have an adjoining anteroom which allows exclusive passage for personnel to the work room. The anteroom shall not have entrances or exits opening directly to the exterior. 

B. Dressing facilities for exclusive use of personnel working in the aseptic room. 

Based on the above discussion we are now ready to start a real experiment. Molasses are transferred from the sugar industry and kept in a cool room. The ATCC culture order has arrived and hydrated. Stock culture was prepared and aseptic transfer successfully done. 

All laboratory operations are carried out in laminar flow cabinets in rooms in which filtered air is maintained at a slight positive pressure relative to their outer environment. Operators wear sterilized clothing and work aseptically. Antibiotic fermentations are, of strict necessity, pure culture aseptic processes, without con-tamirrating orgarrisms. 

One of the most potent routes for transmission of bacterial disease is via the air. Cross-infeetion in hospital wards, infeetion in operating theatres, the transmission of disease in elosed spaces such as cinemas and other places of assembly, in the ward rooms and erew s quarters of ships and in submarines are all well known. Of equal importance is the provision of a bacteria-fiee environment for aseptic manipulations generally. Clearly, the disinfeetion of atmospheres is a worthwhile field of study and to this end much research has been done. It is equally clearly important to be able to evaluate preparations claimed to be air disinfeetants. 

The greatest risk of contamination of a pharmaceutical product comes from its immediate environment. Additional protection from particulate and microbial contamination is therefore essential in both the filling area of the clean room and in the aseptic unit. This can be provided by a protective work station supplied with a unidirectional flow of filtered sterile air. Such a facility is known as a laminar airflow unit in which the displacement of air is either horizontal (i.e. from back to front) or vertical (i.e. from top to bottom) with a minimum homogenous airflow rate of 0.45 ms" at the working position. Thus, airborne contamination is not added to the work space and any generated by manipulations within that area is swept away by the laminar air currents. 

Articles which are to he discharged from the clean room (or elsewhere) to the aseptic area must he sterilized. To achieve this they should be transferred via a double-ended sterilizer (i.e. with a door at each end). If it is not possible, or required, that they be discharged directly to the aseptic area, they should be (i) double-wrapped before sterilization (ii) transferred immediately after sterilization to a clean environment until required and (iii) transferred from this clean environment via a double-doored hatch (where the outer wrapping is removed) to the aseptic area (where the inner wrapper is removed at the workbench). Hatchways and sterilizers should be arranged so that only one side of the entry into an aseptic area may be opened at any one time. Solutions manufactured in the clean room may be brought into the aseptic area through a sterile 0.22-/im bacteria-proof membrane filter. 

Sample Preparation. Liquid crystalline phases, i.e. cubic and lamellar phases, were prepared by weighing the components in stoppered test tubes or into glass ampoules (which were flame-sealed). Water soluble substances were added to the system as water solutions. The hydrophobic substances were dissolved in ethanol together with MO, and the ethanol was then removed under reduced pressure. The mixing of water and MO solutions were made at about 40 C, by adding the MO solution dropwise. The samples for the in vivo study were made under aseptic conditions. The tubes and ampoules were allowed to equilibrate for typically five days in the dark at room temperature. The phases formed were examined by visual inspection using crossed polarizers. The compositions for all the samples used in this work are given in Tables II and III. 

People are the principal source of contamination in clean room operations. All personnel involved throughout the development and production of a parenteral product must be aware of the factors that influence the overall quality of a product as well as the factors on which they directly impinge. It is of particular importance that production personnel be properly trained so that human error is minimized. They should be made aware of the use of the products with which they are involved and the importance of following all procedures, especially proper aseptic techniques. Procedures must be set up to verify that the product is being manufactured as intended. After manufacture of a batch, production tickets must be carefully checked, sterilization charts examined, and labels verified for correctness and count. 

A laminar flow enclosure provides a means for environmental control of a confined area for aseptic use. Laminar flow units utilize HEPA filters, with the uniform movement of air along parallel lines. The air movement may be in a horizontal or vertical direction and may involve a confined area, such as a workbench, or an entire room. Laminar flow modules are suspended above filling lines, vial- and stopper-washing equipment, and other processes to provide an aseptic and particulate-free environment. 

The main advantage of this polymerization is that it can be carried out at room temperature without an energy input. PACA nanoparticles have been prepared reproducibly at a semi-industrial level and can be made aseptically [57]. 

As already stated, for aseptic BFS, the container is filled in a localized air shower provided with sterile filtered air. However, there is a short period of time between container formation and filling, when the open container is transferred from the par-ison formation position to the filling position and exposed to the clean room environment. During this shuttling period, there is a possibility for contaminants from the room environment to enter the container. The air used to form the parison (parison support air) is typically sterile filtered air. If this is not the case, it is also possible for nonsterile air to enter the parison during parison formation. 

Routes of air-borne eontamination into BFS containers have been investigated during a study using sulfur hexafluoride (SFg) tracer gas [3]. During this experiment, the tracer gas was released into a elean room, housing an aseptic BFS machine, at a known concentration. Levels of the traeer gas were measured within subsequently filled BFS units. The study coneluded that the container was effeetively protected by the localized air shower. Although not necessarily representative of deposition of microbial contaminants, there was also eonclusive evidence of some room air within... 

The equipment needed is determined by the type and extent of the services chosen to provide. Hospitals already utilize laminar flow hoods for aseptic compounding of sterile solutions. The same hoods can be used to compound other sterile products such as eye drops. A balance, preferably electronic, is essential. Ointment slabs (pill tiles), along with spatulas of different types and materials, should be on hand. A few mortars and pestles (both of glass, ceramic, and/or plastic) should be obtained and some glassware. It may not be necessary to buy a roomful of equipment, but one should purchase what is needed to start the service, and build it up as the service grows and expands to different arenas. 

Aseptic techniques are used to avoid the possibility of infection of the animals or ceU cultures. These include the preparation of the vaccines and spleens under aseptic conditions in a class 100 clean room equipped with a laminar airfiow hood, sterilization of instruments, and treatment of work surfaces with disinfectant before and after use, washing of the investigator s hands with an antiseptic surgical scrub preparation, and wearing of sterile gloves, face mask, and eyeglasses. 

Figure 3.3. Operator wearing clean room clothing suitable for working under aseptic conditions. Note that his entire body is covered. This precludes the possibility of the operator shedding skin, microorganisms or other particulate matter into the product. Photo courtesy of SmithKline Beecham Biological Services s.a., Belgium...

Downstream processing is normally undertaken under clean room conditions, with the final steps (e.g. sterile filtration and aseptic filling into final product containers) being undertaken under Grade A laminar flow conditions (Figure 3.18). 

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