bacteria 5,6 Flashcards
when does microbial contamination occur
during manufacturing process and products escape quality assurance checks
what are the impacts of microbial contamination
medicine unfit for use, potential litigation, financial loss, limits supply to patients, health hazards, infections, endoxins
what medicine components/pharmaceutical ingredients are at risk of microbial attacks
active drugs- metabolised to less potent/chemically inactive forms
non/anionic surfactants- alkyl/alkylbenzene sulphonates are readily metabolised
organic polymers (thickening agents)- microbial depolymerisation
humectants- readily metabolised in low amounts
fats/oils- attacked when dispersed in aqueous formulations
sweeteners/flavourings/colouring agents- substrates for bacteria, high conc are resistant to degradation
how to resist microbial contamination
use preservatives
what are visible signs of contamination
unpleasant smell, sour taste, appearance change, texture/viscosity changes, sedimentation, production of bubbles, cracking, change in efficacy
what causes viscosity and textures to change when a medicine component is contaminated
metabolism of thickening agents or sugar polymerisation
what are preservatives used for
resist microbial contamination
factors that affect/cause microbial contamination of a pharmaceutical product
type/size of inoculum, nutritional factors, moisture content (greater solute conc=lower water activity), redox potential, storage temp, pH, packaging design protection of microorganisms in pharmaceutical products
list some non-antibiotic antimicrobials available
antiseptics, disinfectants, preservatives, creams/ointments, disinfectant sprays, biocides, alcohol based gel scrubs
describe how the non-antibiotic antimicrobial, antiseptics, work
destruction/inhibition of microorganisms on living tissue, against sepsis, prevents systemic infection, non toxic to host, ex vivo use (wounds, mouth)
what is ex vivo
outside living body
what is sepsis
body doesnt respond properly to an infection
describe how the non-antibiotic antimicrobial, disinfectants, work
removes microorganisms from inanimate objects/surfaces, kills/reduce numbers to a level that is acceptable for defined purpose, most are too toxic to use on body tissue
describe how the non-antibiotic antimicrobial, preservatives, work
added to pharmaceutical,cosmetics,foods to prevent microbial contamination, non toxic, lower activity level than antiseptics and disinfectants
what trait must a preservative have to be considered efficient
effective against two bacterias, a yeast and a mould
a chemical exhibits antimicrobial activity if…
it interacts and enters a host cell
how do non-antibiotic antimicrobials initially interact with the cell wall/membrane
electrostatic or hydrophobic interactions