Time-engineeringed biphasic drug release by electrospun nanofiber meshes.

A drug-loaded nanofiber mesh which could achieve time-engineeringed biphasic release was fabricated through sequential electrospinning. The drug to polymer ratio of each single mesh was allocated and designed before the tri-layered meshes were created. The resultant meshes had the following construction: (i) the first drug-loaded mesh (top side), (ii) the second drug-loaded mesh (second side), and (iii) the third drug-loaded mesh (bottom side). The drug release speed and duration were controlled by designing morphological features of the electrospun meshes such as the fiber diameter and mesh thickness. An in vitro release experiment revealed that the tri-layered construction with distinct morphological features of each component mesh can provide biphasic drug release. The time-engineeringed dual release system using the multilayered electrospun nanofiber meshes was proved to be a useful formulation when achieving controlled drug release at different times.

Oral fast-dissolving drug delivery membranes prepared from electrospun polyvinylpyrrolidone ultrafine fibers.

Oral fast-dissolving drug delivery membranes (FDMs) for poorly water-soluble drugs were prepared via electrospinning technology with ibuprofen as the model drug and polyvinylpyrrolidone (PVP) K30 as the filament-forming polymer and drug carrier. Results from differential scanning calorimetry, x-ray diffraction, and morphological observations demonstrated that ibuprofen was distributed in the ultrafine fibers in the form of nanosolid dispersions and the physical status of drug was an amorphous or molecular form, different from that of the pure drug and a physical mixture of PVP and ibuprofen. Fourier-transform infrared spectroscopy results illustrated that the main interactions between PVP and ibuprofen were mediated through hydrogen bonding. Pharmacotechnical tests showed that FDMs with different drug contents had almost the same wetting and disintegrating times, about 15 and 8 s, respectively, but significantly different drug dissolution rates due to the different physical status of the drug and the different drug-release-controlled mechanisms. 84.9% and 58.7% of ibuprofen was released in the first 20 s for FDMs with a drug-to-PVP ratio of 1:4 and 1:2, respectively. Electrospun ultrafine fibers have the potential to be used as solid dispersions to improve the dissolution profiles of poorly water-soluble drugs or as oral fast disintegrating drug delivery systems.

Novel oral fast-disintegrating drug delivery devices with predefined inner structure fabricated by Three-Dimensional Printing.

OBJECTIVES: Novel fast-disintegrating drug delivery devices with special inner structure characteristics were designed and fabricated using Three-Dimensional Printing. METHODS: Based on computer-aided design models, fast-disintegrating drug delivery devices containing loose powders were prepared automatically using the Three-Dimensional Printing system. The inner powder regions were prepared by depositing the binder solutions onto selected regions during the layer-printing process. RESULTS: The devices showed acceptable pharmacotechnical properties and fine hardness (63.4 N/cm(2)) due to the synergistic action of several binding mechanisms, but unsatisfactory friability, with 3.55% total mass loss during the friability tests. Scanning electron microscope images clearly showed that the printed regions were well bound, and that the drug particle size was reduced or individual particles could no longer be distinguished. In contrast, the unprinted regions were uncompacted, with cracks and fissures among the loose mixed powder. All the drug delivery devices disintegrated and wetted rapidly in in-vitro tests. The average disintegration and wetting times were 23.4 s and 67.6 s, respectively. Dissolution tests showed that 98.5% of the drug was released within 2 min. CONCLUSIONS: Three-Dimensional Printing offers strategies for the development of novel oral fast-disintegrating drug delivery devices.

[The improvement of poorly water-soluble drug solubility through electrospun drug-loaded nanofibers].

The improving effect of electrospun drug-loaded nanofibers on the solubility of poorly water-soluble drug was investigated in the present research. Drug-loaded nanofibers were successfully prepared using electrospinning process with helicid as the poorly water-soluble model drug and polyvinylpyrrolidone K60 (PVP K60) as the filament-forming matrix. Scanning electron microscopy observation demonstrated that the nanofibers had a three-dimensional continuous web structure, and had well smooth surface and a diameter between 400-600 nm. X-ray diffraction results suggested that helicid lost its original crystal structure but highly distributed into the nanofibers in an amorphous state, resulting from the hydrogen bonding interactions between the carboxylic group of PVP K60 and the hydroxyl groups of helicid. The drug-loaded nanofibers obviously improved helicid's solubility, and were able to completely release the whole drug in 60 s. Electrospun drug-loaded nanofibers can improve the solubility and release profiles of poorly water-soluble drug.