Polymeric films composed of mixture of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) are prepared from casting combined solvent (methylene chloride and methanol in 1:1 ratio) containing 8% weight/volume of both polymers (EC to HPC in 1:3 weight ratio). The structural and optical studies of the films are carried out by X-ray diffraction and UV–vis spectrophotometer. The films are polycrystalline structure with an average grain size from 23.15 to 10.79 nm. The possible optical transition in these films is found to be allowed direct transition. The optical band gap energy (Eg) is estimated to be 5.02 eV for HPC–EC plain film and then decreases with increasing the filler content reaching to 4.24 eV for the film filled with maximum Se80Te14Sn6 content of 1 w%. This suggests that Se80Te14Sn6, as filler, is a good choice to control the optical properties of HPC–EC blend film.

Polymeric films composed of mixture of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) are prepared from casting combined solvent (methylene chloride and methanol in 1:1 ratio) containing 8% weight/volume of both polymers (EC to HPC in 1:3 weight ratio). The structural and optical studies of the films are carried out by X-ray diffraction and UV–vis spectrophotometer. The films are polycrystalline structure with an average grain size from 23.15 to 10.79 nm. The possible optical transition in these films is found to be allowed direct transition. The optical band gap energy (Eg) is estimated to be 5.02 eV for HPC–EC plain film and then decreases with increasing the filler content reaching to 4.24 eV for the film filled with maximum Se80Te14Sn6 content of 1 w%. This suggests that Se80Te14Sn6, as filler, is a good choice to control the optical properties of HPC–EC blend film.

Polymeric films composed of mixture of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) are prepared from casting combined solvent (methylene chloride and methanol in 1:1 ratio) containing 8% weight/volume of both polymers (EC to HPC in 1:3 weight ratio). The structural and optical studies of the films are carried out by X-ray diffraction and UV–vis spectrophotometer. The films are polycrystalline structure with an average grain size from 23.15 to 10.79 nm. The possible optical transition in these films is found to be allowed direct transition. The optical band gap energy (Eg) is estimated to be 5.02 eV for HPC–EC plain film and then decreases with increasing the filler content reaching to 4.24 eV for the film filled with maximum Se80Te14Sn6 content of 1 w%. This suggests that Se80Te14Sn6, as filler, is a good choice to control the optical properties of HPC–EC blend film.

The determination of sodium cromoglicate (SCG) and fluorometholone (FLU) in ophthalmic solution was developed by simple, sensitive and precise methods. Three spectrophotometric methods were applied: absorptivity factor (a-Factor method), absorption factor (AFM) and mean centering of ratio spectra (MCR). The linearity ranges of SCG were found to be (2.5–35 µg/mL) for (a-Factor method) and (MCR); while for (AFM), it was found to be (7.5–50 µg/mL). The linearity ranges of FLU were found to be (4–16 µg/mL) for (a-Factor method) and (AFM); while for (MCR), it was found to be (2–16 µg/mL). The mean percentage recoveries/RSD for SCG were found to be 100.31/0.90, 100.23/0.57 and 100.43/1.21; while for FLU, they were found to be 100.11/0.56, 99.97/0.35 and 99.94/0.88 using (a-Factor method), (AFM) and (MCR), respectively. A TLC-spectrodensitometric method was developed by separation of SCG and FLU on silica gel 60 F254 using chloroform : methanol : toluene : triethylamine in the ratio of (5:2:4:1 v/v/v/v) as developing system, followed by spectrodensitometric measurement of the bands at 241 nm. The linearity ranges and the mean percentage recoveries/RSD were found to be (0.4–4.4 µg/band), 100.24/1.44 and (0.2–1.6 µg/band), 99.95/1.50 for SCG and FLU, respectively. A comparative study was conducted between the proposed methods to discuss the advantage of each method. The suggested methods were validated in compliance with the ICH guidelines and were successfully applied for the determination of SCG and FLU in their laboratory prepared mixtures and commercial ophthalmic solution in the presence of benzalkonium chloride as a preservative. These methods could be an alternative to different HPLC techniques in quality control laboratories lacking the required facilities for those expensive techniques.

Three simple, sensitive, and specific methods were developed for simultaneous determination of amlodipine besylate (AML) and Perindopril Erbumine (PER) without previous separation. The first method was dependent on the first derivative of the ratio spectra by measuring the amplitudes at 348 nm for amlodipine using 50 µg mL1 of perindopril as a divisor and at 227 nm for perindopril using 30 µg mL1 of amlodipine as a divisor. The second method was based on ion-pair RP-HPLC. Satisfactory resolution was achieved using RP-C18 chromatographic column Zorbax Extend column and a mobile phase consists of potassium dihydrogen phosphate buffer (0.05 M, pH 3.00.02 adjusted by orthophosphoric acid): acetonitrile 30:70 v/v at a flow rate 1 mL/min using 0.002 M sodium heptanesulfonate in the aqueous phase. UV detection was performed at 215 nm. The third method was based on TLC; the separation was carried out on Fluka TLC aluminum sheets silica gel 60 F254, using n-butanol : water : glacial acetic acid (4:5:1, v/v/v) as the mobile phase. The validation of the proposed methods was applied according to ICH guidelines and LOD and LOQ were calculated. The suggested methods were successfully applied for the determination of the cited drugs in bulk powder and commercial tablets.

Aim: To conduct a comparative study between the smart novel ratio difference spectrophotometric method (RDSM) versus four spectrophotometric methods: first derivative spectrophotometry (D1), first derivative of the ratio spectra (1DD), isoabsorpative point (Aiso), ratio subtraction (RS), and two chemometric techniques based on principal component regression (PCR) and partial least-squares (PLS-1) for the determination of a binary mixture of Ofloxacin (OFX) and Dexamethasone (DXM). Study Design: The results obtained from the proposed methods were statistically compared to the reported HPLC method using student’s t-test, F-test and One way ANOVA. Methodology: (OFX) was determined by the application of direct spectrophotometry, by measuring its zero-order (D0) absorption spectra at its λmax = 296.6 nm. (DXM) was determined by (D1) at 227.1 nm. By applying (1DD), (DXM) was determined at 237.3. The total concentration of both (OFX + DXM) was determined at their isoabsorpative point λiso= 238.3 nm, then the concentration of (DXM) in mixtures were calculated by subtraction. (DXM) was determined using the (RS) method at its λmax = 239 nm. (DXM) was determined using (RDSM) by measuring amplitude difference at two selected wavelengths (248.4 and 290 nm). A concentration of 10 μg.mL1 of OFX was used as a divisor. The linearity range was found to be (1-10 μg.mL1) and (2-14 μg.mL1) for OFX and DXM respectively. Results: The recovery percentage for OFX was found to be 100.07 ± 0.65 and for DXM was found to be 100.41 ± 0.84, 100.15 ± 0.97, 100.14 ± 0.91, 100.54 ± 0.75 and 100.11 ± 0.66 for the five methods, respectively. Conclusion: The novel method showed advantages over the other proposed methods regarding simplicity, minimal data manipulation and maximum reproducibility and robustness; which enabled the analysis of binary mixtures with overlapped spectra for routine quality control testing with quite satisfactory and in lower cost.

Aims: Topical drug delivery of fluconazole, an antifungal drug, in gel form was formulated to avoid the side effect of the oral route. Study Design: In this study I prepare different formulation from different polymers and select the best formulation to undergo further antifungal and stability studies. Place and Duration of Study: Faculty of Pharmacy, Department of Pharmaceutics, Assiut University, between May 2010 and July 2011. Methodology: Different polymers; Sodium carboxymethyl cellulose, Sodium alginate, Carbopol 934P, Hydroxypropylmethyl cellulose, Pluronic F-127 and hydroxypropyl cellulose, were used. The compatibility of fluconazole and different gelling polymer was assessed through differential scanning calorimetry and infrared absorption spectroscopy. The influence of polymer type and concentration on fluconazole release from the prepared gels were studied. The prepared gel formulations were evaluated for pH, drug content, rheology, spreadability and in vitro drug release. Results: The rheological behavior of all the prepared gels showed a pseudoplastic flow (shear thinning) which is a good characteristic in the pharmaceutical gels. With the increase of the polymer concentration in the formulation, viscosity increased and in vitro release of fluconazole decreased. Among all the prepared formulations, 0.5% Carbopol 934P gel showed desired properties and exhibited the best fluconazole in vitro release that reaches 77% over a 3-hr period. This gel showed a good inhibition to the fungal growth against Candida albicans and Trichophyton mentagrophyte using cup plate method and also, showed good stability. Conclusion: 0.5% Carbopol 934P / Fluconazole gel is a promising dosage form for the treatment of superficial fungal infections and could be used for further clinical studies.

Aims: Topical drug delivery of fluconazole, an antifungal drug, in gel form was formulated to avoid the side effect of the oral route. Study Design: In this study I prepare different formulation from different polymers and select the best formulation to undergo further antifungal and stability studies. Place and Duration of Study: Faculty of Pharmacy, Department of Pharmaceutics, Assiut University, between May 2010 and July 2011. Methodology: Different polymers; Sodium carboxymethyl cellulose, Sodium alginate, Carbopol 934P, Hydroxypropylmethyl cellulose, Pluronic F-127 and hydroxypropyl cellulose, were used. The compatibility of fluconazole and different gelling polymer was assessed through differential scanning calorimetry and infrared absorption spectroscopy. The influence of polymer type and concentration on fluconazole release from the prepared gels were studied. The prepared gel formulations were evaluated for pH, drug content, rheology, spreadability and in vitro drug release. Results: The rheological behavior of all the prepared gels showed a pseudoplastic flow (shear thinning) which is a good characteristic in the pharmaceutical gels. With the increase of the polymer concentration in the formulation, viscosity increased and in vitro release of fluconazole decreased. Among all the prepared formulations, 0.5% Carbopol 934P gel showed desired properties and exhibited the best fluconazole in vitro release that reaches 77% over a 3-hr period. This gel showed a good inhibition to the fungal growth against Candida albicans and Trichophyton mentagrophyte using cup plate method and also, showed good stability. Conclusion: 0.5% Carbopol 934P / Fluconazole gel is a promising dosage form for the treatment of superficial fungal infections and could be used for further clinical studies.