Notice of RetractionA Novel Processing Process for Preparing Solid Dispersions of Acyclovir

Notice of Retraction

After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE´s Publication Principles.

We hereby retract the content of this paper. Reasonable effort should be made to remove all past references to this paper.

The presenting author of this paper has the option to appeal this decision by contacting TPII@ieee.org.

In the present study, a novel processing process was successfully developed for preparing solid dispersions (SD) of acyclovir (ACY). During the process, the drug and the hydrophilic polymer polyvinylpyrrolidone were co-dissolved to form aqueous solutions at an evaluated temperature, then the solutions were frozen using liquid nitrogen, following by vacuum freeze drying to prepare the SD. The solubility measurements of ACY under different conditions and the polarization microscope observations gave the warrants for the novel process. The improvement of wettability of the drug in the SD membrane and most of the ACY presented in the amorphous physical status, which were demonstrated by contact angle measurement and X-ray diffraction, obviously facilitated the dissolution process of ACY in the SD membrane. In vitro dissolution tests showed that 84.3% of ACY was released out in first 5 minutes, only 20.6% and 4.29% of ACY could be free into the dissolution media for compressed tablets and pure ACY particles at the same time period. This novel process is useful for preparing SD to improve the dissolution properties of a type of poorly water-soluble drug and free of organic solvents.