betadex and tranilast

Tranilast (TL), an antiallergic agent, has been clinically used in the treatment of bronchial asthma, although its clinical use has been limited by its poor solubility in water, photodegradation and systemic side effects. In this study, we prepared a gel ointment containing TL nanoparticles (TLnano gel ointment), and investigated its usefulness. In addition, we demonstrated the preventive effects of the TLnano gel ointment on inflammation in adjuvant-induced arthritis (AA) rats. The TLnano gel ointment was prepared using Bead Smash 12 (a bead mill) and additives including sodium docusate, 2-hydroxypropyl-β-cyclodextrin, methylcellulose and Carbopol 934; the mean particle diameter of the TL nanoparticles was 71.0±25.4 nm. In in vitro skin penetration experiments, the amount of penetrated TL, the penetration rate (Jc) and the penetration coefficient through the skin (Kp) of the TLnano gel ointment were significantly higher than those of a gel ointment containing TL microparticles (TLmicro gel ointment; particle diameter 50.5±26.3 µm). The TL concentrations in the skin tissue and plasma of rats receiving the TLnano gel ointment were also higher than in rats receiving the TLmicro gel ointment. In addition, the application of the TLnano gel ointment attenuated the increase in paw edema of the hind feet of AA rats in comparison with AA rats treated with the TLmicro gel ointment. These results suggest that TL nanoparticles can be applied to the formulation of a transdermal system, and that a transdermal formulation using TL nanoparticles might be a delivery option for the clinical treatment of RA.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; Acrylates; Administration, Cutaneous; Animals; Anti-Inflammatory Agents; Arthritis, Experimental; Arthritis, Rheumatoid; beta-Cyclodextrins; Edema; Gels; Inflammation; Male; Methylcellulose; Nanoparticles; Ointments; ortho-Aminobenzoates; Particle Size; Rats; Rats, Wistar; Skin; Skin Absorption; Solubility

A synthesis of beta-cyclodextrin (beta-CD) dimer, containing two beta-CD moieties that are linked through their sides by ethylenediamine, was presented. The dimer was characterized by means of IR, (1)H NMR, (13)C NMR, and elemental analysis. The inclusion complexation behavior of beta-cyclodextrin dimer with tranilast was studied in an aqueous KH(2)PO(4)-citric acid buffer solution of pH 2.00 at room temperature by spectrofluorimetry. Based on the significant enhancement of fluorescence intensity of tranilast, a spectrofluorimetric method with high sensitivity and selectivity was developed for the determination of tranilast in bulk aqueous solution in the presence of ethylenediamine beta-CD dimer. The apparent association constant of the complex was 8.39 x 10(3) L mol(-1), and the linear range was 10.8-1.40 x 10(4) ng mL(-1) with the detection limit 3.2 ng mL(-1). There was no interference from the excipients normally used in tablets and serum constituents. The proposed method was successfully applied to the determination of tranilast in serum.

Topics: beta-Cyclodextrins; Carbon Isotopes; Cross-Linking Reagents; Dimerization; Ethylenediamines; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; Molecular Structure; ortho-Aminobenzoates; Protons; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Fluorescence; Spectrophotometry, Infrared