Studies Of Quality Standards, Pharmacokinetics And Tissue Distribution Of Paclitaxel Loaded Human Serum Albumin Nanoparticles

Paclitaxel is extracted from the bark of the western yew diterpenoid natural hydrophobic substances, due to its ablility of promoting tubulin polymerization,which leads cell division mitosis staying in G2-M junction and inducing apoptosis,Paclitaxel plays the anti-apoptotic tumor effect. Taxol has a broad spectrum of anti-tumor effect, but is insoluble in water, conventional paclitaxel injection needed polyoxyethylene castor oil and ethanol to dissolve, prone to hypersensitivity, which limits the clinical use of paclitaxel. Paclitaxel Loaded Human Serum Albumin Nanoparticles(PTX-HSA NPs)drug a drug binded human serum albumin and of Hydrophilic, has good biocompatibility, can reduce toxicity, with better security, so in this paper laboratory-made PTX-HSA NPs quality standard and evaluation in vivo were carried out.Firstly, We analyzed the quality standards of the laboratory made PTX-HSA NPs according to the Chinese Pharmacopoeia(2010 edition) and imported drug registration standards.The results showed that PH of PTX-HSA NPs was approximately 6.51 ± 0.05, the average particle diameter was 128.24 ± 14.67 nm, we carried out method validation experiments both of albumin and paclitaxel, precision(RSD) were 0.10% and 0.24% reproducibility(RSD) were 0.29% and 1.70%,recovery were 97.60% and 98.81%, stability(RSD) were 0.36% and 1.17%,respectively. the drug ratio of paclitaxel to albumin was about 1: 9 of PTX-HSA NPs.This paper established a rapid, sensitive and simple UPLC-MS/MS method for quantitative analysis of lower paclitaxel concentrations in plasma and tissue of rats.Column was Waters BEH-C18 column(2.1 mm ×50 mm, 1.7 μm), mobile phase were acetonitrile and water(0.1% formic acid) with gradient elution,positive electrospray ionization mode(ESI+) was used under multiple reaction monitoring1(MRM) and ion pair of paclitaxel was m/z 854.66→286.22,ion pair of internal standard norethindrone was m/z 299.33→109.05.Combing protein precipitation with liquid-liquid extraction method to prepare plasma and tissue sample.The protein precipitant was acetonitrile and chloroform was uesed as extraction agent.we carried out method validation experiments of UPLC-MS/MS method in plasma,1the results showed that the linear range of paclitaxel plasma standard curve was 3.00~500.00 ng/mL(R2> 0.99), the lowest limit of quantification was 3.00 ng/mL,the recovery was 81.06±6.52%, the matrix effect was 105.51±6.67%, intra-day accuracy(RE) is in the range of-3.98~3.92%, intra-day precision(RSD) was in the range of 3.56~7.26% and the stability(RSD) was in the range of 2.65~8.68%,which were in accordance with the provisions of SDFA.The pharmacokinetic results of PTX-HSA NPs administered to rats showed that compared with paclitaxel Active Pharmaceutical Ingredient(PTX-API), plasma concentration(Cmax) of PTX-HSA NPs group was lower. The area under the curve(AUC0-∞), drug half-life(T1/2), mean residence time(MRT) were 2.13~2.85,1.36~2.45 and 2.46~3.33 times of PTX-API group, respectively. The plasma clearance(CL) was about 35.41%~47.95% of PTX-API group.we carried out method validation experiments of UPLC-MS/MS method in heart,liver, spleen, lung, kidney and brain tissue, the results showed that the linear range of paclitaxel plasma standard curve were 3.00~500.00 ng/mL(R2>0.99), the lowest limit of quantification were 3.00 ng/mL, recoveries were more than 80%, matrix effects were around 100%, intra-day precision(RSD) were in the range of 2.08~8.24%2,intra-day accuracy(RE) were in the range-4.80~3.62%, and the stability(RSD) were in the range of 0.51~10.25% in various tissues, which were in accordance with the provisions of SDFA. The tissue distribution results of PTX-HSA NPs administered to rats showed that the PTX-HSA NPs administration group had higher paclitaxel concentration than PTX-API group in the liver, spleen, lung and kidney tissue significantly in the early stages of administration, tending to the tissue of higher blood flow, with concentration decreased rapidly and slower decreased after 10 h,to maintain a certain concentration.The quality standards of laboratory made PTX-HSA NPs was in accordance with Pharmacopoeia and the imported drug registration standards, pharmacokinetic results showed that PTX-HSA NPs can maintain a certain blood concentration over a longer period of time,and some sustained release, tissue distribution results showed thatcompared with the PTX-API group, PTX-HSA NPs group can distribute more drugs into the tissue, thus PTX-HSA NPs exhibits greater advantage.