Autoclave steaming

The British Pharmacopoeia (1993) recognizes five methods for the sterilization of pharmaceutical products. These are (i) dry heat (ii) heating in an autoclave (steam sterilization) (iii) filtration (iv) ethylene oxide gas and (v) gamma or electron radiation. In addition, other approaches involving steam and formaldehyde and ultraviolet (UV) light have evolved for use in certain situations. For each method, the possible permutations of exposure conditions are numerous, but experience and product stability... 

Autoclave steam sterilization is a well-established and widely used procedure. Normally, steam enters through the top of the chamber (Fig. 9). Being lighter than air, it remains at the top of the chamber but steadily and continuously drives the air out of the chamber through the bottom vent throughout the sterilization cycle. The velocity of steam entering the... 

Autoclave (Steam Sterilizer) Heat Penetration Study of Once in a year ... 

Sterile radiopharmaceuticals may be divided into those which are manufactured aseptically and those which are terminally sterilized. In general, it is advisable to use a terminal sterilization whenever this is possible. Terminal sterilization is defined as a process that subjects the combined product/container/closure system to a sterilization process that results in a specified assurance of sterility [7], Since sterilization of solutions normally means autoclaving (steam sterilization), one must assure that the radiopharmaceutical product does not decompose when it is heated to temperatures above 120°C. Many radiolabeled compounds are susceptible to decomposition at higher temperatures. Proteins, such as albumin, are good examples of this. Others, such as 18F-fluodeoxyglucose (FDG), can be autoclaved in some formulation but not in others. 

Shrink wrapping machine Over printing machine Trays and rack washer Autoclave (steam sterilizer)... 

Medical parts and packages are typically sterilized using ionizing radiation (e-beams. X-rays, or gamma radiation), ethylene oxide (EtO) gas exposure and autoclave steam sterilization. Each has its advantages, as well as potential damaging effects on the polymer, especially if the PO is exposed to multiple treatments. 

To meet the demands in the health care and medical device markets, new transparent PEI blends with improved hydrolysis resistance under the autoclave, steam sterilization conditirms, were developed (Sanner 2011). Based on the known superior hydrolytic stability of the sulfone resins and the published patent literature (Kailasam et al. 2009), it is very likely that these clear, hydrolysis-resistant blends are the compatibilized blends of PEI and polyphenylsulfone (PPSU). 

Steam sterilisation (heating in an autoclave) steam sterilisation or sterilisation with hot water in a closed container, minimum 15 min at 121 °C (Fo = 15). TTie humid heat denamres proteins and DNA of micro-organisms. 

Crimp. The tow is usually relaxed at this point. Relaxation is essential because it gready reduces the tendency for fibrillation and increases the dimensional stabiUty of the fiber. Relaxation also increases fiber elongation and improves dye diffusion rates. This relaxation can be done in-line on Superba equipment or in batches in an autoclave. Generally saturated steam is used because the moisture reduces the process temperatures required. Fiber shrinkage during relaxation ranges from 10 to 40% depending on the temperature used, the polymer composition used for the fiber, and the amount of prior orientation and relaxation. The amount of relaxation is also tailored to the intended apphcation of the fiber product. 

Silica and Alumina. The manufacture of Pordand cement is predicated on the reaction of lime with siUca and alumina to form tricalcium sihcate [12168-85-3] and aluminate. However, under certain ambient conditions of compaction with sustained optimum moisture content, lime reacts very slowly to form complex mono- and dicalcium siUcates, ie, cementitious compounds (9,10). If such a moist, compact mixture of lime and siUca is subjected to steam and pressure in an autoclave, the lime—silica reaction is greatiy accelerated, and when sand and aggregate is added, materials of concrete-like hardness are produced. Limestone does not react with siUca and alumina under any circumstances, unless it is first calcined to lime, as in the case of hydrauhc lime or cement manufacture. 

Most of the textured apparel and industrial yams are woven or knitted directly into fabric. The carpet BCF yams can be tufted directly off package into loop pile or velvet constmctions. For the textured saxony constmctions, the BCF and the spun staple yams must be ply-twisted and heat-set. The heat-setting temperature for nylon-6 and nylon-6,6 is 180—220°C in hot—dry atmosphere, and 120—140°C in saturated steam. The yams are twist-set in pressurized autoclaves or continuously on the Superba and Suesson machines (121). Before setting the twist, the yam is heated and relaxed for predevelopment of the bulk. 

GaUic acid is heated with about half its weight of water in a copper autoclave until the pressure reaches 1.2 MPa (12 atm) and the temperature is 175°C. Steam and carbon dioxide are released but sufficient water is retained to maintain the pyrogaHol as a Hquid. The cooled solution is decolorized with animal charcoal and is then evaporated until the volatile pyrogaHol distills into iron receivers. The sohdified material is purified by repeated distillation, sublimation, or vacuum distillation at 200°C in the presence of diaLkyl phthalates (8). 

Steam (qv) sterilization specifically means sterilization by moist heat. The process cannot be considered adequate without assurance that complete penetration of saturated steam takes place to all parts and surfaces of the load to be sterilized (Fig. 1). Steam sterilization at 100°C and atmospheric pressure is not considered effective. The process is invariably carried out under higher pressure in autoclaves using saturated steam. The temperature can be as low as 115°C, but is usually 121°C or higher. 

Great care is needed in the design of autoclaves and sterilization cycles because of the requirement for the presence of moisture. The autoclave must be loaded to allow complete steam penetration to occur in all parts of the load before timing of the sterilization cycle commences. The time required for complete penetration, the so-called heat-up time, varies with different autoclave constmction and different types of loads and packaging materials. The time may not exceed specific limits in order to guarantee reproducibility and, for porous loads, saturated steam. The volume of each container has a considerable effect on the heatup time whenever fluids are sterilized. Thermocouples led into the chamber through a special connector are often employed to determine heatup times and peak temperatures. The pressure is refleved at the end of each sterilization cycle. Either vented containers must be used or... 

The gravity-displacement-type autoclave rehes on the relative nonmiscibility of steam and air to allow the steam that enters to rise to the top of the chamber and fill it. The air is pushed out through the steam-discharge line located at the bottom of the chamber. Gravity-displacement autoclaves are utilized for the sterilization of Hquids and for unwrapped nonhoUow medical instmments at 134°C. 

The selection of an appropriate steam-sterilization cycle must be made after a carefiil study of the nature of the articles to be sterilized, the type and number of organisms present, type and size of each package, and type of packaging material used. Cycle-development studies may be conducted using fiiU autoclave loads. 

The cmde oxide is pressure-leached in a steam-heated autoclave using water or circulating mother hquor. The arsenic trioxide dissolves, leaving behind a residue containing a high concentration of heavy metal impurities and sihca. The solution is vacuum-cooled and the crystallisation is controUed so that a coarse oxide is obtained which is removed by centrifuging. The mother hquor is recycled. The oxide (at least 99% purity) is dried and packaged in a closed system. 

Although hydration under hydrothermal conditions may be rapid, metastable iatermediate phases tend to form, and final equiUbria may not be reached for months at 100—200°C, or weeks at even higher temperatures. Hence, the temperatures of formation given ia Table 6 iadicate the conditions under saturated steam pressure that may be expected to yield appreciable quantities of the compound, although it may not be the most stable phase at the given temperature. The compounds are Hsted ia order of decreasiag basicity, or lime/siHca ratio. Reaction mixtures having ratios C S = 1 yield xonotHte at 150—400°C. Intermediate phases of C—S—H (I), C—S—H (II), and crystalline tobermorite ate formed ia succession. Tobermorite (1.13 nm) appears to persist indefinitely under hydrothermal conditions at 110—140°C it is a principal part of the biader ia many autoclaved cement—silica and lime—silica products. 

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