STERILIZATION The complete destruction of all living organisms and their spores or their complete removal from the formulation. All parenterals, as well as otic, nasal, ophthalmic solutions, must be sterile, includes packaging materials methods steam dry-heat filtration gas ionizing radiation B. Amsden CHEE 440

Viruses B. Amsden CHEE 440

Bacteria B. Amsden CHEE 440

Bacterial Endospores B. Amsden CHEE 440

Yeast and Mould aspergillus penicillium B. Amsden CHEE 440

Sterilization Methods steam sterilization conducted in an autoclave method of choice 121 C, 20 minutes dry heat less effective than moist heat 170 C, > 2 hours used to sterilize equipment B. Amsden CHEE 440

Heat Resistances method determined by nature of micro-organism and formulation ingredients protocols are developed based on reference organisms of known sterilization resistance micro-organisms possess different resistances to heat B. Amsden CHEE 440

Steam Sterilization Determination of steam sterilization protocol first select a reference organism determine its D value under defined conditions establish initial bioburden calculate time of exposure at 121 ºC B. Amsden CHEE 440

Sterilization Methods Filtration used for heat sensitive solutions pore sizes range from 14 to 0.025 mm Gas sterilization used in hospitals and industry for thermolabile materials ethylene oxide, propylene oxide used 500-1000 mg/L, 4 - 16 hours at 55 ºC, 50-60 %RH need to remove absorbed gas after sterilization Ionization use of gamma rays limited application B. Amsden CHEE 440

Kinetics of Cell Inactivation death rate follows first order kinetics B. Amsden CHEE 440

D value decimal reduction time time required for 90% reduction in cell count B. Amsden CHEE 440

Z value degrees of temperature/dose change required to achieve a tenfold decrease in D B. Amsden CHEE 440

Example Using G. stearothermophilus as a reference organism (D121 = 1.5 min), and an initial bioburden of 1000 spores, determine the sterilization time required to achieve a 1 in 1,000,000 chance of a spore surviving using a steam autoclave. B. Amsden CHEE 440

De-pyrogenation Emphasis is placed on prevention of introduction of pyrogens Removal glassware, metals 250 ºC for 45 minutes water oxidation to nonvolatile solvents using potassium permanganate, then distill reverse osmosis plastics protect against contamination B. Amsden CHEE 440