Preparation, pharmacokinetics and biodistribution of baicalin-loaded liposomes

Abstract

Baicalin (BA) is a major constituent of Scutellaria baicalensis Georgi , a medicinal herb. Previous pharmacokinetic studies of BA showed its low oral bioavailability. The aim of the present study was to develop a novel BA-loaded liposome (BA-LP) to enhance oral bioavailability. BA-LP, composed of BA, Tween ® 80, Phospholipon ® 90H, and citric acid at weight ratio of 96/50/96/50, respectively, was prepared by the effervescent dispersion technique and characterized in terms of morphology, size, zeta potential, encapsulation efficiency, and the in vitro release. Pharmacokinetics and biodistribution studies were carried out in rats after oral administration of BA-LP and a carboxymethyl cellulose suspension containing BA (BA-CMC) as a control. BA-LP exhibited a spherical shape by transmission electron microscopy observation. BA-LP had a mean particle size of 373±15.5 nm, zeta potential of −20.1±0.22 mV, and encapsulation efficiency of 82.7%±0.59%. The BA-LP showed a sustained-release behavior, and the in vitro drug-release kinetic model fit well with the Weibull distribution equation: lnln (1/(1−Q)) =0.609 lnt −1.230 ( r =0.995). The oral bioavailability and the peak concentration of the BA-LP was threefold and 2.82-fold that of BA-CMC, respectively. The in vivo distribution results indicated that drug concentrations were significantly increased in the liver, kidney, and lung in the case of BA-LP, which were 5.59-fold, 2.33-fold, and 1.25-fold higher than those of BA-CMC, respectively. In conclusion, the study suggested that BA-LP might be a potential oral drug delivery system to improve bioavailability of BA.

Mathematical Modeling of Release Kinetics from Supramolecular Drug Delivery Systems

“…This function was and still remains most frequently applied to the analysis of dissolution and release studies involving nanoparticulate drug systems: nano- and micro-capsules [137,138], nanosuspensions [139], nanosized zeolits [140], PLGA nanoparticles [141], inorganic nanoparticles [142,143], solid lipid nanoparticles (SLN), and nano-structured lipid carrier (NLC) [144], as well as different liposomal formulations [145,146,147,148].…”

Encapsulation of ropivacaine in a combined (donor-acceptor, ionic-gradient) liposomal system promotes extended anesthesia time

“…Among them, the zero-order model was the best fit found to describe the curves of RVC release from donor and acceptor liposomes, as shown in S2 Table . As for the combined liposomes, the best fit was achieved with the Weibull model ( S2 Table ), which has been previously used to describe the kinetic curves of other liposomal formulations [ 35 , 36 ]. In that case, the release exponent from Eq 4 (b value, S2 Table ) was greater than unity (sigmoid curve), indicating a complex release mechanism [ 37 ].…”

Regulatory Mechanisms of Baicalin in Cardiovascular Diseases: A Review

“…For example, the baicalin liposomes modified with folic acid and polyethylene glycol (PEG) can improve the cellular uptake rate and tumor targeting, as well as extend the retention time in the body (Chen et al, 2016). Baicalin liposomes are also known to strengthen oral bioavailability and tissue distribution (Wei et al, 2014). Nonetheless, to date, limited information is available relative to baicalin drug delivery systems for AS therapy.…”