Preparation and characterization of non-viral gene delivery systems with pEGFP-C1 Plasmid DNA

In recent years, non-viral delivery systems for plasmid DNA have become particularly important. They can overcome the disadvantages of viral systems such as insertional mutagenesis and unpredicted immunogenicity. Some additional advantages of non-viral gene delivery systems are; good stability, low cost, targetability, delivery of a high amount of genetic materials. The aim of the study was to develop novel non-viral nanosystems suitable for gene delivery. Two formulations were developed for this purpose: water-in-oil microemulsion (ME) and solid lipid nanoparticles (SLN). The microemulsion was composed of Peceol, Tween 80, Plurol oleique, ethanol and water. The SLN was consisting of Precirol, Esterquat-1 (EQ1), Tween 80, Lecithin, ethanol and water. Characterization studies were carried out by measuring particle size, zeta potential, viscosity and pH. TEM imaging was performed on SLN formulations. Protection against DNase I degradation was examined. Cytotoxicity and transfection efficacy of selected formulations were tested on L929 mouse fibroblast cells. Particle sizes of complexes were below 100 nm and with high positive zeta potential. TEM images revealed that SLNs are spherical. The SLN:DNA complexes have low toxicity and good transfection ability. All results showed that the developed SLN formulations can be considered as suitable non-viral gene delivery systems

Kontrollü salım yapan klorheksidin glukonat formülasyonunun hazırlanması

Bacteria in the microbial dental plaque are the main cause of periodontal diseases. Conventional periodontal treatment aims at removal of plaque and calculus as well as the diseased cementum from the tooth surfaces. In certain circumstances, conventional periodontal treatment fails to treat periodontal diseases successfully or periodontal disease may recur. In such cases, adjunctive use of antimicrobial agents is accepted to be feasible. The present study has been conducted in order to prepare a controlled release system including chlorhexidine gluconate. The prepared chlorhexidine gluconate pellets have been hardened for variable time periods and their in vitro release profiles have been evaluated both in distilled water and synthetic saliva and compared with those of PerioChip;amp;reg;. The chlorhexidine gluconate pellet, which has been hardened for 24 hours exhibited similar release profile to that of PerioChip;amp;reg; in synthetic saliva. As a result, it may be concluded that the prepared pellets are promising for clinical application. However, further biodegradability studies and in vivo release tests are required before it can be used in periodontal treatment.Mikrobiyal dental plak bakterileri periodontal hastalıkların ortaya çıkmasında ana etkendir. Konvansiyonel periodontal tedavide plak ve diştaşları ile kök yüzeylerindeki hastalıklı semenim mekanik işlemlerle uzaklaştırılması hedeflenir. Ancak, bazı durumlarda konvansiyonel periodontal tedavi hastalığı durdurmada yetersiz kalabilir ya da periodontal hastalık tekrarlayabilir. Böyle olgularda, mekanik tedavi işlemlerinin antimikrobiyal maddeler ile desteklenmesinde yarar olduğu kabul edilmektedir. Bu çalışma, kontrollü salım yapan klorheksidin glukonat formülasyonunun hazırlanması amacıyla gerçekleştirilmiştir. Farklı sürelerde sertleştirilerek yapılan klorheksidin glukonat ypelletlerin hem distile suda hem de yapay tükürük ortamında in vitro salım profilleri değerlendirilmiş ve ayrıca PerioChip® ile karşılaştırılmıştır. Hazırlanmış olan klorheksidin glukonat pelletlerden 24 saat süreyle sertleştirilmiş olanın yapay tükürük ortamındaki salım profilinin PerioChip® ile benzerlik gösterdiği belirlenmiştir. Sonuç olarak, hazırlanmış olan bu pelletlerin klinik kullanım için umut vaad ettiği ancak, öncesinde biyobozunurluk çalışmalarının ve in vivo salım testlerinin gerçekleştirilmesi gerektiği görüşündeyiz

Comparison of different water/oil microemulsions containing diclofenac sodium: Preparation, characterization, release rate, and skin irritation studies

The aim of the present study was to make a comparison of the in vitro release rate of diclofenac sodium (DS) from microemulsion (M) vehicles containing soybean oil, nonionic surfactants (Brij 58 and Span 80), and different alcohols (ethanol [E], isopropyl alcohol [I], and propanol [P]) as cosurfactant. The optimum surfactant:cosurfactant (S:CoS) weight ratios and microemulsion areas were detected by the aid of phase diagrams. Three microemulsion formulations were selected, and their physicochemical properties were examined for the pH, viscosity, and conductivity. According to the release rate of DS, M prepared with P showed the significantly highest flux value (0.059±0.018 mg/cm2/h) among all formulations (P<.05). The conductivity results showed that DS-loaded microemulsions have higher conductivity values (18.8–20.2 microsiemens/cm) than unloaded formulations (16.9–17.9 microsiemens/cm), and loading DS into the formulation had no negative effect on system stability. Moreover, viscosity measurements were examined as a function of shear rate, and Newtonian fluid characterization was observed for each microemulsion system. All formulations had appropriate observed pH values varying from 6.70 to 6.85 for topical application. A skin irritation study was performed with microemulsions on human volunteers, and no visible reaction was observed with any of the formulations. In conclusion, M prepared with P may be a more appropriate formulation than the other 2 formulations studied as drug carrier for topical application