ORIGINAL RESEARCH ARTICLE Supramolecular Complex of Ibuprofen with Larch Polysaccharide Arabinogalactan: Studies on Bioavailability and Pharmacokinetics Mikhail V. Khvostov 1 • Sergey A. Borisov 1 • Tatjana G. Tolstikova 1,4 • Alexander V. Dushkin 2 • Biligma D. Tsyrenova 2 • Yulia S. Chistyachenko 2 • Nikolay E. Polyakov 3 • Galina G. Dultseva 3,4 • Andrey A. Onischuk 3,4 • Sergey V. An’kov 1 Ó Springer International Publishing Switzerland 2016 Abstract Background and Objectives In the present work, pharma- cological and pharmacokinetic properties of the supramolecular complex of non-steroid anti-inflammatory drug ibuprofen (IBU) with natural polysaccharide arabino- galactan (AG) were studied. The main goals of such com- plexation were the increase of ibuprofen’s bioavailability and decrease its effective dose after oral administration. Methods The complex with mass ratio as IBU:AG 1:10 was obtained by mechanochemical synthesis and charac- terized by water solubility, electron microscopy, differen- tial scanning calorimetry, X-ray powder diffraction analysis and 1 H-nuclear magnetic resonance spectroscopy. Different animal models of pain and inflammation was used to investigate IBU:AG biological effects. Plasma concentration of IBU and its pharmacokinetic parameters were evaluated after oral introduction. Results It was found that ibuprofen’s effective analgesic and anti-inflammatory dose decreased twofold after its intro- duction as a complex with AG. The reason of this difference is due to the increase of ibuprofen concentration in rats’ plasma: C max of IBU at doses of 20 and 40 mg/kg was found as 0.088 and 0.132 lg/ml, whereas C max of IBU in the complex form was 0.103 and 0.160 lg/ml, respectively. Conclusions Thus, we have shown that complexation of the IBU with AG results in its bioavailability increase, reduction of the effective dose and should decrease toxic side effects. Key Points Using mechanochemical synthesis the supramolecular complex of IBU with AG was synthesized. Complexation of the IBU with AG results in IBU’s effective oral dose reduction. Blood concentration of the IBU after oral introduction in AG complex is higher than in free form. 1 Introduction Oral drug delivery is the most popular route because of the low expenses and long-term compliance. In addition, oral drug delivery increases the therapeutic value of the drugs [1]. However, this introduction route has some limitations for drug molecules. One of them is the water solubility. It is well known that more than 40 % of all drugs are poorly soluble or insoluble in water [2]. Most prominent water Electronic supplementary material The online version of this article (doi:10.1007/s13318-016-0357-y) contains supplementary material, which is available to authorized users. & Mikhail V. Khvostov mihail.hvostov@gmail.com 1 Laboratory of Pharmacological Research, N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 9, Lavrentjeva Prospect, 630090 Novosibirsk, Russia 2 Institute of Solid State Chemistry and Mechanochemistry SB RAS, Novosibirsk 630090, Russia 3 Voevodsky Institute of Chemical Kinetics and Combustion, SB RAS, Novosibirsk 630090, Russia 4 Novosibirsk State University, Novosibirsk 630090, Russia Eur J Drug Metab Pharmacokinet DOI 10.1007/s13318-016-0357-y