Two novel microwell-based spectrophotometric methods with high throughput have been developed and validated for the determination of ciprofloxacin (CIP), a fluoroquinolone antimicrobial agent. These methods were based on the formation of colored condensation products upon reaction of CIP with each of 1,2-naphthoquinone-4-sulphonic acid sodium salt (NQS) and the oxidized pyrocatechol (OPC). These reactions were carried out in a 96-microwell plate and the absorbance of the colored-product was measured by a microwell plate absorbance reader at 460 and 510 nm for NQS and OPC, respectively. The variables affecting the reactions were carefully investigated and the conditions were optimized. The stoichiometry of the reaction was determined, and the reactions pathways were postulated. The proposed reactions were found to be highly selective for CIP among many fluoroquinolone members. Under the optimum conditions, good linear relationships were obtained between the absorbances and the concentrations of CIP in the ranges of 25–200 and 40–450 μg/mL with limits of detections of 3.66 and 8.79 mg/mL for the methods based on NQS and OPC, respectively. The robustness and ruggedness of the methods were satisfactory. The methods were successfully applied to the bulk drug and pharmaceutical dosage forms; the percentage recoveries were 98.0-101.5 (0.45 ± 1.63%). The results were compared favorably with those obtained by a pre-validated reference method; no significant difference in accuracy and precision as revealed by the accepted values of t– and F–tests, respectively.

Two novel microwell-based spectrophotometric methods with high throughput have been developed and validated for the determination of ciprofloxacin (CIP), a fluoroquinolone antimicrobial agent. These methods were based on the formation of colored condensation products upon reaction of CIP with each of 1,2-naphthoquinone-4-sulphonic acid sodium salt (NQS) and the oxidized pyrocatechol (OPC). These reactions were carried out in a 96-microwell plate and the absorbance of the colored-product was measured by a microwell plate absorbance reader at 460 and 510 nm for NQS and OPC, respectively. The variables affecting the reactions were carefully investigated and the conditions were optimized. The stoichiometry of the reaction was determined, and the reactions pathways were postulated. The proposed reactions were found to be highly selective for CIP among many fluoroquinolone members. Under the optimum conditions, good linear relationships were obtained between the absorbances and the concentrations of CIP in the ranges of 25–200 and 40–450 μg/mL with limits of detections of 3.66 and 8.79 mg/mL for the methods based on NQS and OPC, respectively. The robustness and ruggedness of the methods were satisfactory. The methods were successfully applied to the bulk drug and pharmaceutical dosage forms; the percentage recoveries were 98.0-101.5 (0.45 ± 1.63%). The results were compared favorably with those obtained by a pre-validated reference method; no significant difference in accuracy and precision as revealed by the accepted values of t– and F–tests, respectively.

The present study aims to investigate the possibility of interaction of donepezil (DP) and galantamine (GAL) as acetylcholinestrase inhibitors, on memantine (MT) hydrochloride in rat plasma by HPLC-fluorescence detection. The separation of MT was achieved within 12 min without interference of DP and GAL on the chromatogram. MT levels in rat plasma with a single administration of MT (2.5 mg/kg, i.p.) and those with a co-administration of DP (5.0 mg/kg, i.p.) and GAL (3 mg/kg, i.p.) were monitored. MT concentrations determined in rat plasma ranged from 10.0 to 245.6 ng/mL. Significant difference was observed in the behavior of MT with a co-administration of DP, while no significant difference was observed with a co-administration of GAL.

The aim of this study was to synthesize and evaluate novel biodegradable polyesters namely; poly(ethylene glycol)-Poly(glycerol adipate-co--pentadecalactone), PEG-PGA-co-PDL-PEG, and poly(ethylene glycol methyl ether)-Poly(glycerol adipate-co--pentadecalactone), PGA-co-PDL-PEGme as an alternative sustained release carrier for lung delivery compared with non-PEG containing polymer PGA-co-PDL. The co-polymers were synthesized through lipase catalysis ring opening polymerization reaction and characterized using GPC, FT-IR, 1H-NMR and surface contact angle. Furthermore, microparticles containing a model hydrophilic drug, sodium diclofenac, were prepared via spray drying from a modified single emulsion and characterized for their encapsulation efficiency, geometrical particle size, zeta potential, tapped density, primary aerodynamic diameter, amorphous nature, morphology, in vitro release and the aerosolization performance. Microparticles fabricated from mPEG-co-polymer can be targeted to the lung periphery with an optimum in vitro deposition. Furthermore, a significantly higher in vitro release (p>0.05, ANOVA/Dunnett’s) was observed with the PEG and mPEG-co-polymers compared to PGA-co-PDL. In addition, these co-polymers have a good safety profile upon testing on human bronchial epithelial, 16HBE14o- cell lines.

A simple and selective micellar electrokinetic chromatographic (MEKC) method has been developed for the analysis of five pharmaceutical binary mixtures containing three non-steroidal anti-inflammatory drugs (NSAIDs). The investigated mixtures were Ibuprofen (IP)–Paracetamol (PC), Ibuprofen (IP)–Chlorzoxazone (CZ), Ibuprofen (IP)–Methocarbamol (MC), Ketoprofen (KP)– Chlorzoxazone (CZ) and Diclofenac sodium (DS)–Lidocaine hydrochloride (LC). The separation was run for all mixtures using borate buffer (20 mM, pH 9) containing 15% (v/v) methanol and 100 mM sodium dodecyl sulphate (SDS) at 15 kV and the components were detected at 214 nm. Different factors affecting the electrophoretic mobility of the seven investigated drugs were studied and optimized. The method was validated according to international conference of harmonization (ICH) guidelines and United States pharmacopoeia (USP). The method was applied to the analysis of five pharmaceutical binary mixtures in their dosage forms. The results were compared with other reported high performance liquid chromatographic methods and no significant differences were observed.

We described the health resource utilisation (HRU) and associated direct medical costs of managing epilepsy in children and young people (CYP) using population-level data from the United Kingdom. The study cohort were CYP born between 1988 and 2004 who were newly diagnosed with epilepsy and identified using a nationally representative primary care database from the United Kingdom. Reference unit costs were applied to each element of HRU to calculate annual direct medical costs per child. We assessed whether HRU and costs differed by time from diagnosis, age, sex and socioeconomic deprivation. Of 798 CYP newly diagnosed with epilepsy, 56% were male and the mean age at diagnosis was 5.6 years. The highest burden of HRU was in the first year following diagnosis with a mean annual cost of £930 (95% confidence interval (CI) £839-1022) per child in this first year. This decreased to £461 (95%CI 368-551) in the second year which remained fairly constant each subsequent year (£413 (95% CI 282-540) in the 8th year). The highest contribution to the annual medical costs was from inpatient hospital admissions followed by the costs of AEDs. Mean annual medical costs were significantly higher in children under 6 years of age compared with older children (p 0.01), but were similar across socioeconomic groups (p = 0.62). The direct medical costs of HRU in CYP with epilepsy are higher in the first year after diagnosis compared to subsequent years, reflecting HRU related to the diagnostic process in the first year. Medical costs did not vary substantially by sex or socioeconomic deprivation indicating a similar level of consultation and care across these groups.

Abstract A rapid, sensitive and selective flow injection analysis (FIA) method was developed for the determination of some selective 1-blockers including; terazosin (TER), doxazosin (DOX), prazosin (PRZ), and alfuzosin (ALF). The method was based on enhancement of the native fluorescence of the studied drugs in the presence of sodium dodecyl sulfate (SDS). The method was optimized for the buffer type, concentration and pH, surfactant type and concentration, flow rate and detection wavelengths in order to achieve the maximum sensitivity. The results showed that the best sensitivity was obtained by using SDS (10 mM) in phosphate buffer (20 mM, pH=3), flow rate was 0.5 ml/min and the detector was set at λex= 250 and λem= 389. Under these optimum conditions there was a linear relationship between the concentration and the fluorescence intensity in the range from 5–400 ng ml−1 with correlation coefficient of more than 0.998. The detection and quantitation limits for the studied drugs by the proposed method were 3.2–11.9 ng ml−1 and 10.8–39.7 ng ml−1, respectively. The method was validated in accordance with the requirements of ICH guidelines and shown to be suitable for intended applications. Moreover, the binding constants for 1–blockers –SDS system were determined using the adduct model. The proposed method has been applied successfully for the analysis of the pure forms for studied drugs and also their pharmaceutical formulations and the results were compared with official methods.

Abstract A rapid, sensitive and selective flow injection analysis (FIA) method was developed for the determination of some selective 1-blockers including; terazosin (TER), doxazosin (DOX), prazosin (PRZ), and alfuzosin (ALF). The method was based on enhancement of the native fluorescence of the studied drugs in the presence of sodium dodecyl sulfate (SDS). The method was optimized for the buffer type, concentration and pH, surfactant type and concentration, flow rate and detection wavelengths in order to achieve the maximum sensitivity. The results showed that the best sensitivity was obtained by using SDS (10 mM) in phosphate buffer (20 mM, pH=3), flow rate was 0.5 ml/min and the detector was set at λex= 250 and λem= 389. Under these optimum conditions there was a linear relationship between the concentration and the fluorescence intensity in the range from 5–400 ng ml−1 with correlation coefficient of more than 0.998. The detection and quantitation limits for the studied drugs by the proposed method were 3.2–11.9 ng ml−1 and 10.8–39.7 ng ml−1, respectively. The method was validated in accordance with the requirements of ICH guidelines and shown to be suitable for intended applications. Moreover, the binding constants for 1–blockers –SDS system were determined using the adduct model. The proposed method has been applied successfully for the analysis of the pure forms for studied drugs and also their pharmaceutical formulations and the results were compared with official methods.

A selective and new spectrophotometric method is described for determination of five 1,4-dihydropyridine drugs (1,4- DHP); namely nifedipine (NIF), nicardipine (NIC), nimodipine (NIM), felodipine (FEL) and amlodipine (AML). The method is based on a coupling reaction between the cited drugs and vanillin reagent in acidic condition. Under optimized conditions, the red coloured products were measured at 500 nm for NIF, NIC, NIM and FEL or at 479 nm for AML. Molar absorptivities were ranged from 0.575×104 - 1.065×104 l•mol−1•cm−1, Beer’s law was obeyed at 5-70 μg/mL concentration range and the limit of detection was ranged from 0.150-1.500 μg/mL. The proposed method was successfully extended to pharmaceutical preparations tablets and capsules and comparison by Student’s t-test and variance ratio F-test showed no significant difference.

A simple, accurate and selective colorimetric method was developed and validated for determination of five of 1,4-dihydropyridine drugs (1,4-DHP) using tetrabutylammonium hydroxide reagent (TBAH). The proposed method was based on addition of TBAH to the studied drugs then the produced yellow colors were measured spectrophotometrically. Different variables which affecting the reaction conditions were carefully studied and optimized. Under the optimum conditions, Beer's law was obeyed in the concentration range of 2.50-40.0 μg/mL and the limits of detection were ranged from 0.750-1.956 μg/mL. The proposed method was successfully extended to the pharmaceutical preparations, tablets and capsules. The obtained results were comparable with that obtained by the reference methods.