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.

The objectives of the current study are (i) to maximize the ocular bioavailability of dorzolamide hydrochloride (DZD) through; (a) enhancement of the DZD corneal transport using various concentrations of selected natural terpene-4-ol enhancers, (b) increasing the contact time of the drug with the absorbing tissues of the eye using selected carbopol-934 (C-934) as mucoadhesive to reduce the extensive pre-corneal loss of the installed dose due to the physiologically normal fast tear-washout, and (ii) to assess the in vivo intraocular pressure (IOP) lowering effects of the gel test formulations using normotensive New Zealand albino rabbits. In this study, DZD was formulated as 2% formulations ophthalmic gels containing different concentrations of C-934 as mucoadhesive, as well as, with various concentrations of terpene-4-ol as a natural corneal penetration enhancers. The transport of DZD from the gel formulations was quantitatively determined using in vitro diffusion experiments. The permeability parameters of DZD were calculated employing the most appropriate mathematical equations. Further, the in vivo IOP lowering effects of the test formulations were also assessed using the TONO-PEN®XL applanation tonometer in normotensive New Zealand albino rabbits. The overall results revealed that there is a direct correlation between both the in vitro permeability parameters and the contact period with the ocular tissues and the in vivo ΔIOP. In such case, the in vitro permeability parameters of DZD could be used as a determinant for the in vivo IOP measurements. The magnitude of the DZD-IOP lowering effects as well as the durations of actions for the test formulations has been found to be greatly dependent upon (a) the concentration of the terpene-4-ol corneal penetration enhancer and (b) the duration of contact period with the ocular tissues, which was found to be a single-valued function of the C-943 mucoadhesive concentration.

The purpose of this study was to develop a cell-based screening assay for identification of small molecules for the treatment of asthma. Eosinophils are leukocytes that contribute to the pathology of asthma. Lidocaine inhibits interleukin-5 (IL-5)-mediated survival and activation of human eosinophils, and it is able to replace inhaled glucocorticoids for the treatment of asthma; however, lidocaine has many side effects, including anesthesia. Therefore, a collection of commercial and novel, synthesized lidocaine analogues were investigated for inhibitory activity of the IL-5-stimulated proliferation of TF-1 cells, a CD34+, cytokine-dependent, erythroleukemic cell line model for eosinophil growth. Among 74 investigated compounds, 10 were more potent inhibitors of cell proliferation than lidocaine (average IC50 = 223 µM), with IC50 values ranging within 1-119 µM. This cell-based assay is an effective method for screening chemical compounds and has revealed promising lead compounds for the treatment of asthma.

A combinatorial library composed of eleven hydrazides A-K and eleven indolin-1,2-dione derivatives 1-11 has been designed to formally generate sublibraries of 22 mixtures, M1-M22 comprising of 121 Schiff bases, A-K(1-11). The designed library has been synthesized by the solution-phase method and microwave-assisted synthetic techniques. The formation of individual compounds of each mixture was confirmed by Direct Analysis in Real Time (DART) as ionization technique connected to an Ion Trap as a mass detector. The synthesized mixtures were evaluated for their antimycobacterial activity against four Mycobacterium strains; M. intercellulari, M. xenopi, M. cheleneoi and M. smegmatis. Variable antimycobacterial activity was revealed with the investigated mixtures and maximum activity was shown by M8, M10, M11, and M15 with MIC values of 1.5, 3.1, 6.2 and 0.09 μg/mL, respectively. Application of the indexed method of analysis on these active mixtures revealed that compounds D8, D10 and D11 may contribute to the activity of the tested mixtures.

A facile and efficient method for synthesis of fenamic acid hydrazides from their acids in one-step reaction under microwave irradiation and solvent-free conditions was developed. Compared with the two-step conventional heating method, the process was simple, the reaction time was very short and the yields were almost quantitative.

In the title compound, C17H16N6O2S, an intramolecular N—H…O interaction generates an S(6) ring. The pyridine ring makes a dihedral angle of 71.38 (11)° with the thiophene ring. In the crystal, molecules are linked by a pair of N—H…N hydrogen bonds, forming an inversion dimer. The dimers are stacked in columns along the b axis through weak intermolecular C—H…N hydrogen bonds.