1. Microsponges: An Overview Hamid Husain, Divya Juyal, Archana Dhyani
Microsponge and Nanosponge delivery System was originaly developed for topical delivery of drugs can also be used or controled oral delivery of drugs using water soluble and bioerodible polymers. Microsponge delivery system (MDS) can entrap wide range of drugs and then release them onto the skin over a time by difusion mechanism to the skin. It is a unique technology for the controled release of topical agents and consists of nano or micro porous beads loaded with active agent and also use for oral delivery of drugs using bioerodible polymers.
2. Artemisinin (ART) Drug Delivery Using Mixed Non-ionic Surfactants and Evaluation of Their Eficiency in Diferent Cancer Cell Lines Elnaz Asgharkhani, Aazam Najmafshar, Mohsen Chiani
This study aims to investigate the efects of diferent non-ionic surfactants on physicochemical properties of ART niosomes. ART is a natural compound that is used as an antimalarial and chemotherapy agent in medicine. ART has low bioavailabilty, stabilty and solubilty. In order to solve these problems and enhancing the eficiency of the drug, nanotechnology was used. In the present study, several niosomal formulations of ART prepared using diferent molar ratios of Span 60 : Twen 60 : PEG-60: ART in PBS. These thre formulations were FI (1:1:0.5:0.5), FI (2:1:0.5:0.5) and FII (1:2:0.5:0.5), respectively. The encapsulation eficiency was measured by HPLC and the drug release was evaluated by dialysis method. The cytotoxicity test was determined by MTT asay. The size, zeta potential and polydispersity index of the vesicles was measured by Zeta Sizer. Stabilty study was performed within two months. The MTT asay results showed that cytotoxicity efect of these formulations on MCF-7 cel line is beter than C6 cel line and the FII had the best results for both of them. The entrapment eficiencies of the formulations I, I and II were obtained 82.2±1.8%, 75.5±0.92% and 95.5±1.23%, respectively. The results of size, zeta potential and polydispersity index indicated that he size of the vesicles is below 20 nm, their surface charge is about -35 mV and they were monodisperse. Stabilty and release study indicated that the formulation II has the best stabilty and release patern. Therefore, the use of PEGylated niosomal ART can efectively improve its therapeutic index, stabilty and solubilty.
3. Spherical Crystalization: An Overview Sumant Saini
In 1986, Kawashima developed the spherical crystalization technique for size enlargement of drugs in the field of pharmacy. Spherical crystalization is defined as “An aglomeration proces that transforms crystaline drug directly into compact spherical forms for improving the flowabilty, solubilty and compactabilty”. General methods for preparing spherical crystalization are spherical aglomeration, emulsion solvent difusion method, ammonia difusion method and neutralization method. Factors controling the proces of aglomeration include solubilty profile, mode and intensity of agitation, temperature of the system and residence time. Spherical crystals can be characterized by Optical microscopy, X-ray powder difraction, Electron scanning microscopy, Fourier Transform Infrared spectrometer (FTIR) and diferential scaning calorimeter DSC). Spherical crystalization has wide aplications in pharmaceuticals like improvement of flowabilty and compresibilty of porly compresible drugs, masking bitter taste of drugs and improving the solubilty and disolution rate of porly soluble drugs. Conclusion: Sphericaly aglomerated crystals can be directly converted into a tablet hus saving time and reducing cost