A rapid and efficient approach for the preparation and modification of a versatile class of functional polymer nanoparticles has been developed, for which the entire engineering process from small molecules to polymers to nanoparticles bypasses typical slow and inefficient procedures and rather employs a series of steps that capture fully the “click” chemistry concepts that have greatly facilitated the preparation of complex polymer materials over the past decade. The construction of various nanoparticles with functional complexity from a versatile platform is a challenging aim to provide materials for fundamental studies and also optimization toward a diverse range of applications. In this paper, we demonstrate the rapid and facile preparation of a family of nanoparticles with different surface charges and functionalities based on a biodegradable polyphosphoester block copolymer system. From a retrosynthetic point of view, the nonionic, anionic, cationic, and zwitterionic micelles with hydrodynamic diameters between 13 and 21 nm and great size uniformity were quickly formed by suspending, independently, four amphiphilic diblock polyphosphoesters into water, which were functionalized from the same parental hydrophobic-functional AB diblock polyphosphoester by click-type thiol-yne reactions. The well-defined (PDI 1.2) hydrophobic-functional AB diblock polyphosphoester was synthesized by an ultrafast (5 min) organocatalyzed ring-opening polymerization in a two-step, one-pot manner with the quantitative conversions of two kinds of cyclic phospholane monomers. The whole programmable process starting from small molecules to nanoparticles could be completed within 6 h, as the most rapid approach for the anionic and nonionic nanoparticles, although the cationic and zwitterionic nanoparticles required ca. 2 days due to purification by dialysis. The micelles showed high biocompatibility, with even the cationic micelles exhibiting a 6-fold lower cytotoxicity toward RAW 264.7 mouse macrophage cells, as compared to the commercial transfection agent Lipofectamine.

Poor solubililty of drugs is the major obstacle associated with formulation development. Application of nanotechnology in the formulation development of poorly soluble drugs as nanosuspensions offers the opportunity to address many of the deficiencies associated with these compounds. Therefore, the aim of present study was to develop and evaluate nanosuspensions of albendazole in order to enhance its dissolution, which in turn will ehnace its oral bioavailability. Different nanosuspensions of albendazole were prepared using high pressure homogenization and ultrasonic homogenization techniques. The preliminary study showed that smaller particle sizes of drug were obtained by increasing stirring rate, stirring time, ultrasound intensity and number of cycles. Three different stabilizers (poloxamer 188, polyvinyl alcohol [PVA] and polyvinyl pyrrolidone [PVP]) were investigated either alone or in combination to produce nanoususpensions. Prepared nanoparticles were characterized physically using scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and X-ray diffraction. Prepared formulations were also subjected to in vitro dissolution studies in 0.1 N HCl. The results revealed that poloxamer 188 produces nanoparticles with significantly larger particle size than PVA and PVP. However, combination of PVA and PVP produces nanoparticles with significantly smaller size than other formulations. DSC and X-ray diffraction showed that the crystallinity of the drug was decreased. The dissolution rate of the drug in 0.1 N HCl was significantly higher due to the reduction of the particle size of different formulations and the presence of the hydrophilic stabilizers.

A novel potentiometric sensor was prepared, characterized and utilized for static and continuous determination of cefazolin sodium (CFZN). Several metal-ion complexes and anion exchangers were tested as electroactive materials in plasticized polymeric membranes for selective detection of CFZN. Among different electroactive species tridodecyl methyl ammonium chloride (TDMAC) doped membrane electrode was found to exhibit optimal response characteristics. The optimized membrane sensor exhibited near-Nernstian responses (-55.64 mV decade-1) over CFZN concentration range of 0.41–10 mM as measured in 50 mM acetate buffer, pH 5.5. The proposed sensor offers the advantage selectivity, does not require pre-treatment and possible interfacing with computerized and automated systems. It is worth noting that the developed membrane electrode exhibited good selectivity toward CFZN over other cephalosporins such as; cefradine, ceftazidime, cefadroxil, cefaclor and cefoperazone, as well as some additives encountered in the pharmaceutical preparations and so these sensors were successfully used for determination of CFZN. A tubular-type detector incorporating a TDMAC based membrane sensor was prepared and used under hydrodynamic mode of operation for continuous CFZN quantification. The tubular-type detector exhibited a concentration range from 0.5-10 mM with a near-Nernstian response (-53.91 mV decade-1). Continuous monitoring of CFZN offers the advantages of simple design, ease of construction and possible applications to small volumes of drug solutions without pre-treatment. The developed sensor was utilized successfully in static and continuous modes of operation for the determination of CFZN in dosage forms. The results obtained were in good agreement with the standard method of CFZN analysis.

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.