Sterile surfaces

Viscous fluids Sterilized surface required Polished surface required Future expansion required Space restrictions Barrier coolant services Slurry applications... 

Filtered air may be used to purge a complete room, or it m be confined to a specific area and incorporate the principle of laminar flow, which permits operations to be carried out in a gentle current of sterile air. The direction of the airflow may be horizontal or vertical, depending upon the type of equipment being nsed, the type of operation and the material being handled. It is important that there is no obstruction between the air supply and the exposed product, since this may resnlt in the deflection of microorganisms or particulate matter fiom a non-sterile surface and canse contamination. Airflow gauges are essential to monitor that the correct flow rate is obtained in laminar flow units and in complete suites to ensure that a positive pressure fiom clean to less clean areas is always maintained. 

Lewis, K. and Klibanov, A.M. (2005) Surpassing nature rational design of sterile-surface materials. Trends in Biotechnology, 23, 343—348. 

Process simulation units shall not be required to be inverted at some point during the incubation period. All hlled units shall be sufficiently manipulated to assure the contact of all sterile surfaces by the growth media prior to incubation. Momentary inversion of test units shall be surfaces of the container/closure system. Reconciliation requirements of process simulation units shall be equivalent to the requirement for production. The target will be 100% reconciliation/accountability of all hlled units. Any excursion must be investigated and documented however, a variance is not an automatic invalidation of a process simulation test. Process simulation testing shall simulate normal production as closely as possible because its purpose is to assess the potential of contamination in units representative of normal production. 

Abstract In this review, the general principles of antimicrobial surfaces will be discussed in detail. Because many common products that keep microbes off surfaces have been banned in the past decade, the search for alternatives is in full run. In recent research, numerous new ways to produce so-called self-sterilizing surfaces have been introduced. These technologies are discussed with respect to their mechanism, particularly focusing on the distinction between biocide-releasing and non-releasing contact-active systems. New developments in the catalytic formation of biocides and their advantages and limitations are also covered. The combination of several mechanisms in one surface modification has considerable benefits, and will be discussed. 

Once the materials have been sterilized, interventions near either the formulation or product contact surfaces/parts should be minimized. Direct handling of these materials should only be done with sterilized tools or implements nonsterile objects, such as operator gloves, should never directly contact a sterilized surface. Sampling, filter integrity testing, process connection, and other activities should all be designed to eliminate the need for personnel exposure to sterile items. 

Patent Number US 6080490 A1 20000627 ACTIVELY STERILE SURFACES Burrell R E Rosenfeld A M Westaim Technologies Inc. 

The ability of this medical micro-plasma system to sterilize surface has been demonstrated by Misynetal. (2000). Staphylococcus culture in liquid media ( 2 10 cfu/ml) have been treated by the air plasma plume of 3 mm diameter, incubated for 24 h, and counted (see Table 12-8). A 6-log reduction in viable bacteria is achieved in 25 s of treatment however the sterilization efficiency drops off with increasing volume of liquid which inhibits UV penetration and diffusion of active species generated in plasma. Nevertheless, the microplasma system should be a good solution for treatment of living human and animal skin as the bacteria are normally at much lower concentrations on skin (< 10 cfu/cm ). 

The modification of polymers and fibrous surfaces to alter the porosity, wettability and other characteristics of polymeric substrates, will enable the prodnction of implants and biomedical devices which exhibit greater resistance to microbial adhesion and biofilm formation. A nnmber of polymers have been developed that can be incorporated into cellulose and other materials, which will provide significant advances in many fields snch as food packaging, textiles, wound dressings, coating of catheter tnbes and sterile surfaces. 

Plasma treatment of microfluidic surfaces can be used to improve microdevice functionality, to build devices through bonding processes, and to activate and sterilize surfaces. Future directions for this technology include improved modeling of techniques with respect to parameter and surface plasma interaction. The development of refined experimental methods, theoretical models, and experimental studies is required to have more control over plasma treatment within microchannels. 

Modified scratch-free surface coatings are used in the automotive industry. Selfcleaning or self-sterilizing surfaces or windows with important applications are used in food industry and health care. 

Liquid phase properties Chemical composition, temperature, pH/ionic strength, viscosity, toxicity, volatility, flammability, sterility, surface tension, value... 

Plasma processing can sterilize surfaces and can be scaled up for a variety of industrial production applications relatively mote easily. 

Another common disinfectant used in a wine laboratory is 70% v/v ethanol. Ethanol is typically used to sterilize surfaces as well as utensils (forceps, scalpels, hockey sticks, etc.) that are repeatedly used during the... 

In addition to adding surface functional groups, plasma can be used to remove organic contaminants and sterilize surfaces. In this process, plasma radicals break the covalent bonds and oxidize the surface contaminants, which are then cleared by the vacuum. Here, we will outline the basic methodology of gas plasma modification in microchannels, including theory, experimental methods, pertinent process parameters and characterization methods. Additionally, key research findings will be discussed. 

Lerouge S, Tabrizian M, Wertheimer MR, Marchand R, Yahia L. Safety of plasma-based sterilization surface modifications of polymeric medical devices induced by Sterrad and Plazlyte processes. Biomed Mater Eng 2002 12 3. 

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