Loratadine Tablets
Loratadine Tablets contains not less than 95.0 per cent and not more than 105.0 per cent of C22H23ClN2O2.
Usual strengths. 5 mg;10 mg.
Identification
Extract a quantity of the powdered containing 50 mg of loratadine with 20 ml of acetone, filter and evaporate the filter to dryness. The residue complies with the following test. Deterimine by infrared absorption spectrophotometry (2.4.6). Compare the spectrum with that obtained with loratadine RS or with the reference spectrum of loratadine.
Tests
Impurity H. Determine by gas chromatography (2.4.13).
Internal standard solution. A 0.002 per cent w/v solution of isoamyl benzoate in dichloromethane.
Test solution. Shake a quantity of powdered tablets containing 20 mg of loratadine with 5.0 ml of dichloromethane and filter. To the filtrate add 1.0 ml of the internal standard solution and 1 ml of reference solution (a) and dilute to 10.0 ml with dichloromethane.
Reference solution (a). A 0.002 per cent w/v solution of loratadine impurity H RS (ethyl 4-oxopiperidine-1-carboxylate) in dichloromethane.
Reference solution (b). To 1.0 ml of internal standard solution add 1.0 ml of the reference solution (a) and dilute to 10.0 ml with dichloromethane.
Chromatographic system
– a fused silica capillary column 25 m x 0.32 mm, packed with poly(dimethyl) siloxane (film thickness 0.52 µm) (such as HP1),
– temperature:
column time temperature
(min.) (º)
0 80
0®1 80
1®23 80®300
33 300
– inlet port 260° and detector at 300°,
– split ratio. 1:30,
– flame ionization detector,
– flow rate: 1.0 ml per minute, using helium as the carrier gas,
– injection volume: 1 µl.
Inject reference solution (b). The test is not valid unless the resolution between the peaks due to impurity H and isoamyl benzoate is not less than 2.0. Calculate the ratio of the area of the peak due to impurity H to the area of the of the peak due to isoamyl benzoate from the chromatogram obtained with reference solution (b).
Inject reference solution (b) and the test solution. In the chromatogram obtained with the test solution the area of the peak due to impurity H to the area of the peak due to isoamyl benzoate is not more than twice the ratio of the peaks obtained with reference solution (b) (0.1 per cent).
Related substances. Determine by liquid chromatography (2.4.14).
Test solution (a). Disperse a quantity of powdered tablets containing 20 mg of loratadine with 10.0 ml of methanol and filter. Dilute 1.0 ml of the filtrate to 2.0 ml with the mobile phase.
Test solution (b). Dilute 1.0 ml of test solution (a) to 100.0 ml and further dilute 1.0 ml to 5.0 ml with the mobile phase.
Reference solution. A 0.1 per cent w/v solution of loratadine impurity standard RS in the mobile phase.
Chromatographic system
– a stainless steel column 25 cm x 4.6 mm, packed with end-capped octadecylsilane bonded to porous silica (5 µm) (such as ODS-3V),
– column temperature: 40°,
– mobile phase: a mixture of 30 volumes of methanol, 35 volumes of 0.05M potassium dihydrogen orthophosphate, adjusted to pH 2.8 with orthophosphoric acid and 40 volumes of acetonitrile,
– flow rate: 1.5 ml per minute,
– spectrophotometer set at 220 nm,
– injection volume: 20 µl.
Name Correction
factor
impurity A1 1.7
impurity E2 1.9
impurity F3 1.6
1 ethyl 4-[(11RS)-8-chloro-11-hydroxy-6,11-dihydro-5H-benzo[5,6]cyclohepta[1,2-b]pyridin-11-yl]piperidine-1-carboxylate,
2 ethyl 4-[(11RS)-8-chloro-6,11-dihydro-5H-benzo[5,6]cyclohepta[1,2-b]pyridin-11-yl]-3,6-dihydropyridine-1(2H)-carboxylate,
3 ethyl 4-[(11RS)-8-chloro-11-fluoro-6,11-dihydro-5H-benzo[5,6]cyclohepta[1,2-b]pyridin-11-yl]piperidine-1-carboxylate.
Inject reference solution. The test is not valid unless the resolution between the peaks due to impurity E and loratadine is not less than 1.5.
Identify any peak corresponding to impurity A, impurity E and impurity F using reference solution and the supplied with loratadine impurity standard RS.
Inject the test solution (a) and (b). In the chromatogram obtained with the test solution (a), the area of any other secondary peak is not more than the area of the principal peak in the chromatogram obtained with test solution (b) (0.2 per cent) and the sum of the areas of all the secondary peaks is not more than 2.5 times the area of the peak in the chromatogram obtained with the test solution (b) (0.5 per cent). Ignore any peak with an area less than 0.25 times the area of the principal peak in the chromatogram obtained with the test solution (b) (0.05 per cent).
Uniformity of content. Complies with the test stated under Tablets.
Determine by liquid chromatography (2.4.14), using the chromatographic conditions and reference solution (a) described in the Assay.
Test solution. Disperse one tablet in sufficient quantity of methanol and dilute with mobile phase to obtain a solution containing 0.01 per cent w/v of loratadine and filter.
Calculate the content of C22H23ClN2O2 in the tablet.
Other tests. Comply with the tests stated under Tablets.
Assay. Determine by liquid chromatography (2.4.14).
Test solution (a). Weigh and powder 20 tablets. Disperse a quantity of powdered tablets containing 20 mg of Loratadine with 20.0 ml of methanol and filter. Dilute 1.0 ml of the filtrate to 10.0 ml with the mobile phase.
Reference solution(a). A 0.01 per cent w/v solution of loratadine RS in the mobile phase.
Reference solution (b). A 0.1 per cent w/v solution of loratadine impurity standard RS in the mobile phase.
Use chromatographic system as described under Related substances.
Inject reference solution (b). The test is not valid unless the resolution between the peaks due to loratadine and impurity E is not less than 1.5.
Inject reference solution (a) and the test solution.
Calculate the content of C22H23ClN2O2 in the tablets.