microbiology different tests are performed like Microbial
limit tests (MLT), Sterility tests,
Bacterial endotoxin testing (BET), viable monitoring,
Growth promotion tests and LBPC etc. In these tests some are qualitative, some are
quantitative and some are semi quantitative tests.
Qualitative tests:
·
Qualitative
tests are given either pass or fail / present or absent.
·
Qualitative
results are typically reported as positive or negative / detected or not
detected.
·
This
type tests provide yes or no answer about sample.
·
In
these type of tests results are not given in form of counting or calculations.
·
Sterility
test is one of the best example of qualitative test because in sterility test,
results would be either pass or fail.
·
In
sterility testing we could check either contamination is present or absent in
the sample.
Quantitative tests:
· Quantitative
tests are given the results numerical (results are like 1,2,3,4 …..etc) information about sample.
· Quantitative
tests are those tests in which results are given in form of counting
or calculations.
· MLT
is one of the example of quantitative test in which results are given
in form of number of cfu's for total aerobic microbial count or total yeast and
mold count.
· But
when we perform pathogen testing in MLT, that pathogen identification part is
qualitative
testing because in pathogen testing we couldn't determine number of cfu's of pathogens but we give the results in form of
pass or fail whether pathogens are present or absent.
·
Colony
counting is another example of quantitative testing in which results are given
in form
of number of cfu's.
Semi quantitative tests:
·
Semi
quantitative tests are given the results less than or grater than results. (ex
: <5 cfu )
·
BET
is one of the example of semi-quantitative test.
·
In
BET if it is performed by gel clot method then it is semi quantitative because
by this method we could either give results in form of less than or greater
than the specified limits.
·
For
example if product Cefotaxime is having BET limit of not more than 0.20 EU/mg
then results would be either less than 0.20 EU/mg or greater than 0.20 EU/mg.
·
In
this, less than 0.20 EU/mg would be pass result and more than 0.20 EU/mg would
be fail result.
·
That's
why it is called semi quantitative test.
Quantitative Tests
|
MLT (Total Aerobic Microbial Count and Total yeast
and mould count)
Viable monitoning,
All Colony counter testing,
LBPC tesing,
All Bioburden testing,
Visual insfection
Media GPT like SCDA, SDA and agar media.
|
Qualitative Tests
|
Sterility Test,
Specified organism Tests (Pathogen test),
Media GPT like SCDM, SDB and liquid medium.
|
Semi quantitative Tests
|
BET,
Dillution Tests (MPN)
|
