2.13: Effectiveness of chemical germicides Flashcards
Chemical germicides are substances designed to:
-reduce the number of pathogens on a surface, in a liquid, or on/in living tissue.
Disinfectants:
-germicides designed for use on surfaces or in liquids (nonliving objects)
Antiseptics:
-germicides designed for use on/in living tissue
Use-dilution test:
-a standard procedure used to measure the effectiveness of disinfectants specifically against pathogenic bacteria
Describe the use dilution test that was done in lab:
-glass beads were coated with living bacteria
-then they were exposed to varying concentrations of test germicides and then transferred to a growth medium
-after some time in the incubation, the medium is examined for growth.
If a solution is sufficient to prevent microbial growth at least ??% of the time is considered a useable dilution of that germicide for a specific population
-95%
What germicides were used?
-bleach
-hydrogen peroxide
-simple green
-isopropyl alcohol
What media was used?
-nutrient broth
What bacteria’s were used?
-E.coli
-Staphylococcus epidermidis
At what temp. and for how long are the test tubes incubated?
-35+2C for 48 hours
what test is used as a standard procedure to measure the effectiveness of disinfectants specifically against pathogenic bacteria:
-use dilution test
What is the difference between a disinfectant and an antiseptic?
-Antiseptics are used on people whereas disinfectants are used on objects
Germicides designed for use on or in living tissue are specifically called:
-antiseptics
TRUE OR FALSE:
If 75% Bleach is effective reducing the number of Staphylococcus aureus you can assume it must also be effective reducing the number of Pseudomonas aeruginosa.
-false
TRUE OR FALSE:
The Use-Dilution Test, glass beads or stainless steel cylinders coated with dead bacteria are exposed to varying concentrations of germicides and then transferred to a growth medium
-FALSE
-bacteria is ALIVE
In the chemical germicides: disinfectant and antiseptics experiment, what is the purpose of control #4?
-To demonstrate that the beads being used were sterile.
Substance used on surfaces (floors, tables, sinks, countertops, surgical instruments, etc.) or in liquids is a:
-disinfectant
Control #1 purpose was:
-to show that broth was sterile
Control #2 was to show that:
-broth was alive
CLEAR BROTH=
TURITY BROTH=
-germicide was strong enough to prevent growth
-germicide was not strong enough to kill microbes, there is growth
