[Effects of different processing methods on effective components and sulfur dioxide residue in Gastrodiae Rhizoma].

The contents of adenosine, gastrodin, 4-hydroxybenzyl alcohol, 4-hydroxybenzaldehyde, parishin and sulfur dioxide residue were compared in differently-processed Gastrodiae Rhizoma to provide the basis for a reasonable processing method of Gastrodiae Rhizoma. The analysis was performed on a Merck Purospher STAR column (4.6 mm x 250 mm, 5 µm) with a mobile phase consisting of methanol and water (containing 0.1% formic acid) under gradient elution at a flow rate of 1.0 mL x min(-1). The eluates were detected at 270 nm, and the column temperature was 35°C. The content of adenosin, gastrodin, 4-hydroxybenzyl alcohol, 4-hydroxy-benzaldehyde and parishin in processing of boiling or sulfur-fumigated were lower than that of in processing of steaming. Furthermore, the sulfur dioxide residue of sulphur-fumigated groups exceed 400 mg x kg(-1). This stable and reliable method will contribute to the quality control of different processed Gastrodiae Rhizoma.

pH-sensitive magnetic alginate-chitosan beads for albendazole delivery.

Novel magnetic alginate-chitosan beads were prepared for the controlled delivery of albendazole. The magnetic beads were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and vibrating sample magnetometry (VSM). The swelling behavior and in vitro release of albendazole from the beads has been investigated. The magnetic hydrogel beads had showed unique pH-dependent swelling behaviors and a continuous release of the entrapped albendazole occurred. From the magnetometer measurements data, the magnetic alginate-chitosan beads also had superparamagnetic property as well as fast magnetic response. The magnetic beads may be used as a magnetic drug targeting system for albendazole in the gastrointestinal tract.

A novel pH-sensitive magnetic alginate-chitosan beads for albendazole delivery.

BACKGROUND: Drug delivery system using polymer-coated magnetic carriers is considered as an effective strategy for passive targeting, which can not only increase drug utilization but also reduce the adverse reaction. With the carriers, sensitivity to physical stimuli (e.g., magnetic field, pH) has been developed and drugs were conjugated to form incorporating magnetic particles, so that drugs could be located to desire position. METHOD: Novel magnetic alginate (Alg)-chitosan (CS) beads loaded with albendazole (ABZ) were prepared and evaluated for pH sensitivity and drug release characteristics. The effects of six different factors (Alg concentration, the weight ratio of drug to polymer, the weight ratio of magnetite nanoparticles to polymer, CaCl2 concentration, CS concentration, the volume ratio of Alg to CS) were studied on the swelling ability of the magnetic beads. The magnetic beads were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, and vibrating sample magnetometry. In addition, the delivery behavior of ABZ from the magnetic beads was studied. RESULT: The magnetic Alg-CS beads had showed unique pH-dependent swelling behaviors and a continuous release of ABZ. From the magnetometer measurements data, the beads also had superparamagnetic property as well as fast magnetic response. CONCLUSION: The pH-sensitive magnetic beads may be used as a magnetic drug targeting system for ABZ in the gastrointestinal tract.