Naga Thirumalesh - Academia.edu (original) (raw)
Uploads
Papers by Naga Thirumalesh
The purpose of the investigation was to develop a new HPLC method for simultaneous estimation of ... more The purpose of the investigation was to develop a new HPLC method for simultaneous estimation of Metformin and
Canagliflozin in pharmaceutical dosage forms. Chromatography was carried out on an ODS 250mm x 4.6 mm, 5
particle size with a isocratic mobile phase composed of Buffer, Acetonitrile and methanol at a flow rate of 1mL/min.
The column temperature was maintained at 30°C and the detection was carried out using a PDA detector at 212
nm. Validation parameters such as system suitability, linearity, precision, accuracy, specificity, limit of detection
(LOD), limit of quantification (LOQ), Stability of sample and standard stock solutions and robustness were studied
as reported in the International Conference on Harmonization guidelines. The retention times for Metformin and
Canagliflozin and were 2.783 min and 3.781 min respectively. The percentage recoveries of Metformin and
Canagliflozin were 100.1% and 100.2% respectively. The relative standard deviation for assay of tablets found to be
less than 2%. The method is fast, accurate, precise and sensitive hence it can be employed for routine quality control
of tablets containing both drugs in quality control laboratories and pharmaceutical industries.
Nimesulide, a widely prescribed anti-inflammatory and analgesic drug belongs to class II under BC... more Nimesulide, a widely prescribed anti-inflammatory and analgesic drug belongs to class II
under BCS and exhibit low and variable oral bioavailability due to its poor aqueous solubility. As
such it needs enhancement in the dissolution rate and bioavailability to derive its maximum
therapeutic efficacy. The objective of the present study is to prepare and evaluate solid dispersions of
Nimesulide in combined carriers, a water dispersible new modified starch namely Starch 1500 and a
water soluble surfactant namely Poloxamer 188 for enhancing the dissolution rate and dissolution
efficiency of Nimesulide in a 22 factorial study. The individual and combined effects of the modified
starch, Starch 1500 and Poloxamer 188 in enhancing the dissolution rate and dissolution efficiency
of Nimesulide were evaluated in a 22 factorial study. Solid dispersions of Nimesulide in Starch 1500
(modified starch) and Poloxamer 188 (surfactant) alone and in combination were prepared as per 22
factorial design by kneading method and were evaluated for dissolution rate and dissolution
efficiency. The dissolution rate (K1) and dissolution efficiency (DE30) of Nimesulide could be
significantly enhanced by solid dispersion in Starch1500 (a water dispersible modified starch) and
Poloxamer 188 (a surfactant). A 9.42, 12.33 and 35.28 fold increase in the dissolution rate (K1) and a
7.24, 5.97 and 12.70 fold increase in the dissolution efficiency (DE30) was observed respectively
with solid dispersions NSD a , NSD b and NSDab when compared to F1 (Nimesulide pure drug).
Combination of Starch 1500 (a water dispersible modified starch) and Poloxamer 188 (a surfactant)
gave a markedly higher enhancement in the dissolution rate (K1) and dissolution efficiency (DE30)
of Nimesulide than is possible with them alone. ANOVA indicated that the individual and combined
effects of Starch 1500 (factor A) and Poloxamer 188 (factor B) in enhancing the dissolution rate (K1)
and dissolution efficiency (DE30) are highly significant (P < 0.01).Hence solid dispersion of
Nimesulide in combined carriers consisting of Starch 1500 and Poloxamer 188 is recommended to
enhance the dissolution rate and dissolution efficiency of Nimesulide, a BCS class II drug.
The purpose of the investigation was to develop a new HPLC method for simultaneous estimation of ... more The purpose of the investigation was to develop a new HPLC method for simultaneous estimation of Metformin and
Canagliflozin in pharmaceutical dosage forms. Chromatography was carried out on an ODS 250mm x 4.6 mm, 5
particle size with a isocratic mobile phase composed of Buffer, Acetonitrile and methanol at a flow rate of 1mL/min.
The column temperature was maintained at 30°C and the detection was carried out using a PDA detector at 212
nm. Validation parameters such as system suitability, linearity, precision, accuracy, specificity, limit of detection
(LOD), limit of quantification (LOQ), Stability of sample and standard stock solutions and robustness were studied
as reported in the International Conference on Harmonization guidelines. The retention times for Metformin and
Canagliflozin and were 2.783 min and 3.781 min respectively. The percentage recoveries of Metformin and
Canagliflozin were 100.1% and 100.2% respectively. The relative standard deviation for assay of tablets found to be
less than 2%. The method is fast, accurate, precise and sensitive hence it can be employed for routine quality control
of tablets containing both drugs in quality control laboratories and pharmaceutical industries.
Nimesulide, a widely prescribed anti-inflammatory and analgesic drug belongs to class II under BC... more Nimesulide, a widely prescribed anti-inflammatory and analgesic drug belongs to class II
under BCS and exhibit low and variable oral bioavailability due to its poor aqueous solubility. As
such it needs enhancement in the dissolution rate and bioavailability to derive its maximum
therapeutic efficacy. The objective of the present study is to prepare and evaluate solid dispersions of
Nimesulide in combined carriers, a water dispersible new modified starch namely Starch 1500 and a
water soluble surfactant namely Poloxamer 188 for enhancing the dissolution rate and dissolution
efficiency of Nimesulide in a 22 factorial study. The individual and combined effects of the modified
starch, Starch 1500 and Poloxamer 188 in enhancing the dissolution rate and dissolution efficiency
of Nimesulide were evaluated in a 22 factorial study. Solid dispersions of Nimesulide in Starch 1500
(modified starch) and Poloxamer 188 (surfactant) alone and in combination were prepared as per 22
factorial design by kneading method and were evaluated for dissolution rate and dissolution
efficiency. The dissolution rate (K1) and dissolution efficiency (DE30) of Nimesulide could be
significantly enhanced by solid dispersion in Starch1500 (a water dispersible modified starch) and
Poloxamer 188 (a surfactant). A 9.42, 12.33 and 35.28 fold increase in the dissolution rate (K1) and a
7.24, 5.97 and 12.70 fold increase in the dissolution efficiency (DE30) was observed respectively
with solid dispersions NSD a , NSD b and NSDab when compared to F1 (Nimesulide pure drug).
Combination of Starch 1500 (a water dispersible modified starch) and Poloxamer 188 (a surfactant)
gave a markedly higher enhancement in the dissolution rate (K1) and dissolution efficiency (DE30)
of Nimesulide than is possible with them alone. ANOVA indicated that the individual and combined
effects of Starch 1500 (factor A) and Poloxamer 188 (factor B) in enhancing the dissolution rate (K1)
and dissolution efficiency (DE30) are highly significant (P < 0.01).Hence solid dispersion of
Nimesulide in combined carriers consisting of Starch 1500 and Poloxamer 188 is recommended to
enhance the dissolution rate and dissolution efficiency of Nimesulide, a BCS class II drug.