Diclofenac is a synthetic, non-steroidal anti-inflammatory and analgesic compound. It is used topically to treat many inflammatory ocular conditions. However, the poor aqueous solubility of its acidic undissociated form, Diclofenac acid (DA), limits its use. As a result, it is used in the form of eye drops containing its salt form, diclofenac sodium (DNa), which has a short duration of action due to its solubility in tears which leads to its rapid drainage from the eye and the patient has to administer it frequently. In light of this, the objective of the present study was to design microemulsion systems for ophthalmic delivery of water insoluble drug, DA. DA-loaded microemulsion was prepared using isopropyl myristate (oil phase), Tween 80 (surfactant), glycerin (co-surfactant) and Sörensen isotonic phosphate buffer pH 7.4 (aqueous phase). Characterization of the prepared formulations including viscosity, pH, particle size analysis, and stability studies were also performed. The pH of the formulations varied within the range of 6.8 and 7.4. The mean droplet size for all formulations of microemulsion was found in the range of 220-480 nm. The formulations showed a sustained release of DA up to 24 h.

Phytochemical investigation of the aerial parts of Sanchezia nobilis Hook. family Acanthaceae has yielded matsutake alcohol (1-octen-3-ol) (1) and four matsutake alcohol glycosides identified as 3-O--glucopyranosyl-1-octen-3-ol (2), 3-O--glucopyranosyl-(16)--glucopyranosyl-1-octen-3-ol (3), 3-O--arabino-pyranosyl-(16)--glucopyran-osyl-1-octen-3-ol (4), and 3-O--arabino-pyranosyl-(16)--glucopyranosyl-(16)--glucopyranosyl-1-octen-3-ol (5). The structures of the isolated compounds were assigned on the basis of different techniques of NMR spectral analysis. Compounds 1–4 have been isolated here for the first time from the family Acanthaceae, while compound 5 is isolated here for the first time from a natural source.

Montelukast (MKST) is a leukotriene receptor antagonist that has been concomitantly used with inhaled corticosteroids (ICS) for its steroid-sparing effect in the long-term management of asthma. However, the simultaneous determination of MKST, when used as ICS tapering therapy, with ICS in human plasma has not yet been reported. A fast and efficient reversed phase monolith HPLC method was developed for simultaneous determination of MKST with some ICS in plasma of asthmatic patients. The separation was achieved on monolith reversed phase column by isocratic mode at a flow rate of 1.0 ml min−1 using a mobile phase consisted of a mixture of acetonitrile and 10 mM phosphate buffer adjusted to pH 3.5 (40:60, v/v) and detected at 240 nm. Betamethasone dipropionate (BDP) was used as the internal standard. All the studied ICS and MKST were efficiently separated within less than 6 min. The obtained linearity range for the developed HPLC method was 0.03-10 µg ml−1 with correlation coefficients > 0.9995 and the detection limits were 0.009-0.016 µg ml−1 in plasma for all the studied drugs. The method was validated in agreement with the requirements of US-FDA guideline and was recommended for the target applications. The method is valuable for investigations concerned with the effective tapering of ICS therapy with MKST in patients with chronic asthma in clinical practice without loss of asthma control.

Montelukast (MKST) is a leukotriene receptor antagonist that has been concomitantly used with inhaled corticosteroids (ICS) for its steroid-sparing effect in the long-term management of asthma. However, the simultaneous determination of MKST, when used as ICS tapering therapy, with ICS in human plasma has not yet been reported. A fast and efficient reversed phase monolith HPLC method was developed for simultaneous determination of MKST with some ICS in plasma of asthmatic patients. The separation was achieved on monolith reversed phase column by isocratic mode at a flow rate of 1.0 ml min−1 using a mobile phase consisted of a mixture of acetonitrile and 10 mM phosphate buffer adjusted to pH 3.5 (40:60, v/v) and detected at 240 nm. Betamethasone dipropionate (BDP) was used as the internal standard. All the studied ICS and MKST were efficiently separated within less than 6 min. The obtained linearity range for the developed HPLC method was 0.03-10 µg ml−1 with correlation coefficients > 0.9995 and the detection limits were 0.009-0.016 µg ml−1 in plasma for all the studied drugs. The method was validated in agreement with the requirements of US-FDA guideline and was recommended for the target applications. The method is valuable for investigations concerned with the effective tapering of ICS therapy with MKST in patients with chronic asthma in clinical practice without loss of asthma control.

Vitamin K homologues are highly lipophilic compounds that require long separation times on chromatographic analysis which does not meet the demand of higher sample throughputs in quality control laboratories. Therefore, this study aimed to develop a new validated high-throughput high-performance thin-layer chromatographic (HPTLC) method to quantify vitamin K homologues including phylloquinone (PK, vitamin K1), menaquinone-4 (MK-4, vitamin K2), and menaquinone-7 (MK-7, vitamin K2). The densitometric analysis was carried out using HPTLC silica gel G 60 F254 plates as the stationary phase. The plates were developed with methanol-ethanol-isopropanol-water (75:5:5:15, v/v/v/v) in the absorbance mode at 254 nm. The retention factors of MK-4, PK, and MK-7 were 0.56, 0.43, and 0.23, respectively. Linearity was found to be in the range of 1-200 ng band1 for PK and MK-4 and 2-200 ng band1 for MK-7 with correlation coefficient of 0.9990 or more. The limits of detection and quantitation were 0.19-0.85 and 0.76-2.5 ng band1, respectively. The method was validated in accordance ICH guidelines. The method was applied for determination of vitamin K homologues in pharmaceutical formulations and food samples after extraction without prior clean-up procedures. The developed HPTLC method provides a useful tool for rapid and efficient high-throughput analysis of vitamin K homologues.

Vitamin K homologues are highly lipophilic compounds that require long separation times on chromatographic analysis which does not meet the demand of higher sample throughputs in quality control laboratories. Therefore, this study aimed to develop a new validated high-throughput high-performance thin-layer chromatographic (HPTLC) method to quantify vitamin K homologues including phylloquinone (PK, vitamin K1), menaquinone-4 (MK-4, vitamin K2), and menaquinone-7 (MK-7, vitamin K2). The densitometric analysis was carried out using HPTLC silica gel G 60 F254 plates as the stationary phase. The plates were developed with methanol-ethanol-isopropanol-water (75:5:5:15, v/v/v/v) in the absorbance mode at 254 nm. The retention factors of MK-4, PK, and MK-7 were 0.56, 0.43, and 0.23, respectively. Linearity was found to be in the range of 1-200 ng band1 for PK and MK-4 and 2-200 ng band1 for MK-7 with correlation coefficient of 0.9990 or more. The limits of detection and quantitation were 0.19-0.85 and 0.76-2.5 ng band1, respectively. The method was validated in accordance ICH guidelines. The method was applied for determination of vitamin K homologues in pharmaceutical formulations and food samples after extraction without prior clean-up procedures. The developed HPTLC method provides a useful tool for rapid and efficient high-throughput analysis of vitamin K homologues.

Ocular Conjunctivitis is one of the main causes of red eye syndrome. The present work focuses on the treatment of ocular conjunctivitis by using combined mechanisms: (1) Formulation of ocular inserts to provide prolonged and sustained release system of the drug. (2) Use of therapeutic agent, as ciprofloxacin hydrochloride in combination with the polymers used. The selected polymers were methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), hydroxypropylcellulose (HPC), and Eudragit RS100 (ERS 100). The developed ocular inserts were evaluated for physic-chemical, mechanical, drug release, drug permeability, and In-vivo characteristics. The ocular inserts showed desired delivery of the drug to the ocular tissue of the rabbit’s eye. In-vivo studies showed that ciprofloxacin hydrochloride had a significant effect on reduction of induced ocular conjunctivitis.

A high performance thin layer chromatography (HPTLC) method was developed and validated for determination of two anti-asthmatic drugs, salmeterol xinafoate and fluticasone propionate in co-formulations. Study was performed on pre-coated silica gel HPTLC plates using n-hexane:ethyl acetate:acetic acid (5:10:0.2) as a mobile phase. A TLC scanner set at 250 nm was used for direct evaluation of the chromatograms in reflectance/absorbance mode. Method was validated according to ICH guidelines. Determination coefficients of calibration curves were found 0.9977 and 0.9936 in the ranges 100–1000 and 200–2000 ng band1 for salmeterol and fluticasone, respectively. Method had an accuracy of 99.5% for salmeterol and 102.01% for fluticasone. Method had the potential to determine these drugs simultaneously from dosage forms without any interference.

A selective and simple kinetic spectrophotometric has been developed, for the first time, for the determination of gatifloxacin (GAT) in its dosage forms. The method was based on the formation of a colored N-vinyl chlorobenzoquinone derivative of GAT by its reaction with 2,3,5,6-tetrachloro-1,4-benzoquinone in presence of acetaldehyde. The formation of the colored product was monitored spectrophotometrically by measuring the absorbances at 655 nm. The factors affecting the reaction were studied and optimized. The stoichiometry of the reaction was determined, and the reaction pathway was postulated. Under the optimized conditions, the initial rate and fixed time (at 5 min) methods were utilized for constructing the calibration graphs. The graphs were linear in the concentration ranges of 2-100 and 10-140 microg ml(-1) with limits of detection of 0.84 and 3.5 microg ml(-1) for the initial rate and fixed time methods, respectively. The analytical performance of both methods was fully validated, and the results were satisfactory. The proposed methods were successfully applied to the determination of GAT in its commercial dosage forms. The label claim percentages were 99.7-100.5 and 98.2-99.5% for the initial rate and fixed time methods, respectively. Statistical comparison of the results with those of the reference method showed excellent agreement and proved that there was no significant difference in the accuracy and precision between the reference and the proposed methods. The proposed methods are superior to all the previously reported spectrophotometric methods in terms of the procedure simplicity and assay selectivity.

A simple and sensitive kinetic spectrophotometric method has been developed and validated for the determination of ciprofloxacin (CIP) and lomefloxacin (LOM) in their pharmaceutical dosage forms. The method was based on the oxidation of CIP and LOM with alkaline potassium permanganate to give a green colored reaction product. The reaction was monitored spectrophotometrically by measuring the absorbance of the reaction product at 610 nm. The factors affecting the reaction was studied and optimized. The stoichiometries of the reaction were determined and the reaction pathway was postulated. The activation energy of the reaction was calculated and found to be 4.48 and 4.17 KJ mole–1 for CIP and LOM, respectively. The initial rate and fixed time (at 5 min) methods were utilized for constructing the calibration graphs. The analytical performance of both methods was fully validated, and the results were satisfactory. The proposed methods were successfully applied to the determination of both CIP and LOM in their commercial pharmaceutical dosage forms. The label claim percentages were 99.4–100.2  1.15–1.81%. Statistical comparison of the results with those obtained by a reference method showed excellent agreement between the accuracy and precision of the two methods. The proposed method has a great value in its application to the analysis of CIP and LOM in quality control laboratories.