Coaxial electrospinning with acetic acid for preparing ferulic acid/zein composite fibers with improved drug release profiles.

This study investigated drug/zein composite fibers prepared using a modified coaxial electrospinning process. With unspinnable acetic acid as sheath liquid and an electrospinnable co-dissolving solution of zein and ferulic acid (FA) as core fluid, the modified coaxial process could run smoothly and continuously without any clogging. Compared with those from the single-fluid electrospinning process, the FA-loaded zein fibers from the modified process were rounder and possessed higher quality in terms of diameter and distribution, as verified by scanning electron microscopic observations of their surface and cross-section. Differential scanning calorimetry and X-ray diffraction showed that fibers from both processes similarly formed a composite with the FA present in the zein matrix in an amorphous state. The driving force of encapsulation of FA into zein fibers was hydrogen bonding, as evidenced by the attenuated total reflectance Fourier transform infrared spectra. However, in vitro dissolution tests demonstrated that the fibers from the coaxial process exhibited better sustained-release profiles with a smaller initial burst effect and less tailing-off release compared with those from the single process. The modified coaxial electrospinning process is a useful tool for generating nanofibers with higher quality and improved functional performance.

[Comparative study on trace elements in natural colored cotton and white cotton].

A method was studied for simultaneous determination of multi-elements in natural colored cotton by microwave digestion and ICP-AES. The contents of Ca, Mg, Fe, Cu, Ba, Zn, Al, Sr, Mn and Si in colored and white cotton were determined by this method. The recovery ratio obtained by standard addition method ranged between 93% and 111%, and the relative standard deviation was below 4% (n = 5). The results showed that the contents of Ca, Cu, Zn, Al, Fe, Sr and Si in green and brown cotton are higher than those in white cotton. The data from the study gives some references for further researches on the colored cotton.

The brain targeting efficiency following nasally applied MPEG-PLA nanoparticles in rats.

The aim of this study was to encapsulate nimodipine (NM) within methoxy poly(ethylene glycol)-poly(lactic acid) (MPEG-PLA) nanoparticles and to investigate its brain targeting efficiency following intranasal administration. NM-loaded nanoparticles, prepared through an emulsion/solvent evaporation technique, were characterized in terms of size, zeta potential, NM loading and in vitro release. The nanoparticles were administered intranasally to rats, and the concentrations of NM in blood, cerebrospinal fluid (CSF) and brain tissues were monitored. The contribution of the olfactory pathway to the uptake of NM in the brain was determined by calculating the brain/plasma concentration ratios and "brain drug direct transport percentage (DTP)" following intranasal administration of the nanoparticles and the solution formulation. The results showed that MPEG-PLA nanoparticles had a mean particle size of 76.5 +/- 7.4 nm, a negative surface charge and a 5.2% NM loading. In vitro release was moderate under sink conditions. The intranasal administration of nanoparticles resulted in a low but constant NM level in plasma. The ratio of AUC values of the nanoparticles to the solution was 1.56 in CSF. The olfactory bulb/plasma and CSF/plasma concentration ratios were significantly higher (P < 0.05) after application of nanoparticles than those of the nasal solution, except the ratio in olfactory bulb at 5 min. Furthermore, nasally administered nanoparticles yielded 1.6-3.3-fold greater DTP values in CSF, olfactory bulb and other brain tissues compared to nasal solution. Thus, MPEG-PLA nanoparticles demonstrated its potential on improving the efficacy of the direct nose-brain transport for drugs.