Objective:
To
develop
three
novel
, sensitive, simple
validated
visible
spectrophotometric methods
for
the quantitative estimation
of
sulfamethoxazole
(SMZ)
and
trimethoprim
(TMP)
in bulk form
.
Method
s:
Methods were based on coupling the d
iazotized
aromatic
primary amino group of the studied drugs with
o-
phenylenediamine
(OPD
) in
an acidic medium
. The first two methods have been proposed for estimation of SMZ
and rest
for
TMP
. The resulting products were m
easured by
spectrophotometric (m
ethod I, II
and
III) tools.
The methods we
re validated as per ICH guidelines
.
Result
s:
In
method
I, the absorbance was measured at 482 and
457 nm with linearity ranges of 4.0
-40.0 and 5.0
-45.0 μg
/ml
for
SMZ
. On the other
hand, method III was
devoted to estimate
TMP
spectrophotometrically
at 457 nm with
linearity range of 5
-
30 μg
/ml
. The
r
2
Conclusio
n:
The study concludes that
visible
spectrophotometric validation method
s can be very efficien
t and economically promising technique
for
the quantitative
analysis of S
MZ
and
TMP
in bulk form
. The statistical analysis of data indicates that the
developed methods were
reproducible
and specific.
It was found that there is a good agreement between the obtained results and those obtained by the reported method
s;
moreover
they
can be
used for
the routine estimations of
SMZ and TMP
in bulk form