and M. Rafiee-Tehrani 4

Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Polymeric delivery systems based on nanoparticles have emerged as a promising approach for peroral insulin delivery. The aim of the present study was to investigate the release of insulin nanoparticulate systems and ex vivo studies. The nanoparticles were prepared by the ion gelation method. Particle size distribution, zeta potential, and polydispersity index of the nanoparticles were determined. It was found that the nanoparticles carried positive charges and showed a size distribution in the range of 170–200 nm. The electrostatic interactions between the positively charged group of chitosan and negatively charged groups of Arabic gum play an important role in the association efficiency of insulin in nanoparticles. In vitro insulin release studies showed an initial burst followed by a slow release of insulin. The mucoadhesion of the nanosystem was evaluated using excised rat jejunum. Ex vivo studies have shown a significant increase in absorption of insulin in the presence of chitosan nanoparticles in comparison with free insulin. 1

doi:10.5402/2011/805983 Research Article Pharmacogenetics and Gender Association with Psychotic Episodes on Nortriptyline Lower Doses: Patient Cases

License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The variation in individual responses to psychotropic drug treatment remains a critical problem in the management of psychotic disorders. Although most patients will experience remission, some patients may develop drug-induced adverse effects that may range from troublesome to life threatening. Antidepressants are freely prescribed by general practitioners, and there should be constant awareness in the medical community about possible serious side effects. We describe two cases of adverse drug reactions on low dosage treatment that led to extreme psychotic episodes as examples of the potential for dangerous side effects. The patients developed adverse reactions on the normal recommended dosage of nortriptyline, a tricyclics antidepressant (TCA). Both were females, with no history of antidepressant treatment, unsocial behaviour, nor any family history of psychosis, but both experienced severe psychiatric symptoms. Pharmacogenetic tests can easily be performed and interpreted according to the likelihood of adverse reactions and should be included in toxicity interpretation. 1

Research Article Development and Validation of a HPLC and an UV Spectrophotometric Methods for Determination of Dexibuprofen in Pharmaceutical Preparations

doi:10.5402/2011/94831

Research Article Separation and Quantification of Eight Antidiabetic Drugs on A High-Performance Liquid Chromatography: Its Application to Human Plasma Assay

License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. An analytical method based on isocratic reverse phase high-performance liquid chromatography was developed and validated for the separation and quantification of eight antidiabetic drugs: rosiglitazone, pioglitazone, glipizide, gliclazide, repaglinide, nateglinide, glibenclamide, and glimepiride for their application in human plasma assay. Metformin is used as internal standard. Analysis was done on Onyx monolithic C18 column (100 × 4.6 mm, i.d., 5 μm) using a mixture of 0.05 % formic acid in water and methanol in the ratio of 42: 58 (v/v) fixed at a flow rate of 0.5 mL/min, and they were monitored at 234 nm. Separation was achieved in less than 20 min. The calibration curves were linear in the range of 50–2000 ng/mL. The method was validated for its recovery, intra- and interday precision, stability, specificity, and selectivity. Plasma samples were prepared using solid-phase extraction of analytes. Hence, the developed method was found to be suitable for the routine analysis of selected antidiabetic drugs in biological matrices. 1

doi:10.5402/2011/627623 Research Article Formulation and Optimization of Sustained Release Stavudine Microspheres Using Response Surface Methodology

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The aim of the current study was to formulate and optimize the formulation on the basis of in vitro performance of microsphere. A3 2 full factorial design was employed to study the effect of independent variables, polymer-to-drug ratio (X1) and stirring speed (X2), on dependent variables, encapsulation efficiency, particle size, and time to 80 % drug release. The best batch exhibited a high entrapment efficiency of 70 % and mean particle size 290 µm. The drug release was also sustained for more than 12 hours. The study helped in finding the optimum formulation with excellent sustained drug release. 1

doi:10.5402/2012/636743 Research Article Development and Stability Studies of Novel Liposomal Vancomycin Formulations

Copyright © 2012 Krishna Muppidi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A promising strategy to improve the therapeutic efficiency of antimicrobial agents is targeted therapy. Although vancomycin has been considered a gold standard for the therapy of MRSA pneumonia, clinical failure rates have also been reported owing to its slow, time-dependent bactericidal activity, variable lung tissue penetration and poor intracellular penetration into macrophages. Liposomal encapsulation has been established as an alternative for antimicrobial delivery to infected tissue macrophages and offers enhanced pharmacodynamics, pharmacokinetics and decreased toxicity compared to standard preparations. The aim of the present work is to prepare vancomycin in two different liposomal formulations, conventional and PEGylated liposomes using different methods. The prepared formulations were optimized for their particle size, encapsulation efficiency and physical stability. The dehydration-rehydration was found to be the best preparation method. Both the conventional and PEGylated liposomal formulations were successfully formulated with a narrow particle size and size distribution and % encapsulation efficiency of 9 ± 2 and 12 ± 3, respectively. Both the formulations were stable at 4 ◦ C for 3 months. These formulations were successfully used t

doi:10.5402/2011/246162 Research Article Preparation and Characterisation of Highly Loaded Fluorescent

License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Chitosan (CS) nanoparticles have been developed as a versatile drug delivery system to transport drugs, genes, proteins, and peptides into target sites. Demands on fluorescent nanoparticles have increased recently due to various applications in medical and stem-cell-based researches. In this study, fluorescent CS nanoparticles were prepared by a mild method, namely, complex coacervation. Entrapment efficiency of sulforhodamine (SR101) loaded into CS nanoparticles was investigated to evaluate their capacity in incorporating fluorescent molecule. Particle size of produced fluorescent nanoparticles was in the range of 600–700 nm, and their particle size was highly dependent on the CS molecular weight as well as concentration. A high entrapment efficiency of SR101 into CS nanoparticles could also be obtained when it was dissolved in methanol. In conclusion, highly loaded fluorescent CS nanoparticles could be easily prepared using complex coacervation method and therefore can be applied in various medical researches. 1

doi:10.5402/2012/764510 Research Article Development of Film Dosage Form Containing Allopurinol for Prevention and Treatment of Oral Mucositis

Copyright © 2012 Yoshifumi Murata et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Film dosage forms (FDs) containing allopurinol (AP) were prepared using a casting method with water-soluble polysaccharides, such as sodium alginate (ALG), and the release profile of AP from FDs was investigated in limited dissolution medium. Some ALGs were able to form FDs incorporating AP, and the thickness was about 50 μm. All FDs were easy to handle, though the rheological properties varied with ALG species. AP was homogenously present throughout the FDs and was released with disintegration in 10 mL of physiological saline. These results confirmed that FDs are useful for preventing or treating localized problems in the oral cavity, such as mucositis. FDs are also useful for administering drugs to cancer patients receiving chemotherapy and/or radiotherapy. 1

doi:10.5402/2011/852619 Research Article Two New Cytotoxic Candidaspongiolides from an Indonesian Sponge

Copyright © 2011 Agus Trianto et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Marine sponges have been recognized as potentially rich sources of various bioactive molecules. In our continuing search for new secondary metabolites from Indonesian marine invertebrates, we collected a sponge, whose extract showed cytotoxicity against cultured cells at 0.1 μg/mL. Purification of the extract yielded two new macrolides 2 and 3 along with known candidaspongiolide (1). The structures for compounds 2 and 3 were elucidated by spectral analysis ( 1 H, 13 C, COSY, HMQC, HMBC) and by comparison of their NMR data with those of 1. Compounds 2 and 3 exhibited a little more potent cytotoxicity (IC50 4.7 and 19 ng/mL) than that (IC50 37 ng/mL) of candidaspongiolide (1) against NBT-T2 cells. 1

doi:10.5402/2011/168539 Research Article Synthesis, Characterization, and Antibacterial Studies of Mixed Ligand Dioxouranium Complexes with 8-Hydroxyquinoline and Some Amino Acids

Copyright © 2011 Sunil S. Patil et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Mixed ligand complexes of dioxouranium (VI) of the type [UO2(Q)(L)·2H2O] have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and amino acids (HL) such as L-threonine, L-tryptophan, and L-isoleucine as secondary ligands. The metal complexes have been characterized by elemental analysis, electrical conductance, magnetic susceptibility measurements, and spectral and thermal studies. The electrical conductance studies of the complexes indicate their nonelectrolytic nature. Magnetic susceptibility measurements revealed diamagnetic nature of the complexes. Electronic absorption spectra of the complexes show intraligand and charge transfer transitions, respectively. Bonding of the metal ion through N- and O-donor atoms of the ligands is revealed by IR studies, and the chemical environment of the protons is confirmed by NMR studies. The thermal analysis data of the complexes indicate the presence of coordinated water molecules. The agar cup and tube dilution methods have been used to study the antibacterial activity of the complexes against the pathogenic bacteria S. aureus, C. diphtheriae, S. typhi, and E. coli. 1