The metabolic and pharmacokinetic studies for HM-3 in rats based on LC-Q-TOF/MS and LC–MS/MS combing a convenient biological sample processing method

Cancer-targeted and glutathione-responsive micellar carriers for controlled delivery of cabazitaxel

Novel type of multifunctional polymeric micelles (PMs) designated as HM-PMss/CTX micelles were developed in the present study for tumor-targeted and glutathione (GSH)-responsive delivery of cabazitaxel (CTX). The surface of the vehicles was modified with piloting molecules (HM-3 peptide), which targets α _v β ₃ integrin overexpressed on cancer cells, and the micelle core was cross-linked by GSH-disintegrable disulfide linkages for controlled drug release. HM-PMss/CTX micelles were prepared using a mixture of two functionalized amphiphilic block copolymers and found to physically encapsulate CTX with excellent entrapment efficiency (93.94 ± 4.19%), drug-loading capacity (8.39 ± 2.28%), and a narrow size distribution. In vitro release profiles showed that CTX remained stably entrapped in the micelles in a release medium without GSH or with GSH of low concentration, while undergoing a rapid release in a highly reductive environment. Cellular uptake experiments showed that the conjugation of the targeting peptide, containing an arginine-glycine-aspartate sequence, enhanced the cellular uptake of HM-PMss/CTX micelles via α _v β ₃ integrin-mediated endocytosis. In vitro cell viability measurements revealed that blank micelles were biocompatible, while HM-PMss/CTX micelles, owing to their tumor-targeting ability and GSH sensitivity, effectively inhibited the proliferation of MDA-MB-231 breast cancer cells. These results indicate that HM-PMss/CTX micelles could be a promising platform for future intelligent drug delivery in cancer therapy.

Rapid profiling and pharmacokinetic studies of multiple potential bioactive triterpenoids in rat plasma using UPLC/Q-TOF-MS/MS after oral administration of Ilicis Rotundae Cortex extract

Triterpenoids, the major bioactive ingredients of Ilicis Rotundae Cortex, contributes a significant cardiovascular protection activity. Although many studies about the total saponins have been reported, the absorption triterpenoids and pharmacokinetic behaviors were unclear. Thus, the present study aims to comprehensive elucidate the absorption triterpenoids and their pharmacokinetics in rats after oral administration the crude extract using UPLC/Q-TOF-MS/MS. A total of forty-two triterpenoids were successfully characterized from the rat plasma, and thirty-two of them were validated by the reference substances, while the others were tentatively identified based on the mass spectral fragmental patterns. Furthermore, the plasma concentrations of six absorption bioactive triterpenoids (rotundinoside C, ilexoside O, pedunculoside, rotundic acid, rotundanonic acid and ilexgenin A) were simultaneously quantified by selected reaction monitoring in negative ionization mode. All analytes exhibited good linearity with correlation coefficients values greater than 0.99 and the LLOQ ranged from 1.2 to 3.2 ng/mL, and method validation for selectivity, precision, accuracy, recovery, matrix effect and stability were reckoned acceptable. The results were successfully applied for the multiple-component pharmacokinetic study of the six bioactive triterpenoids.

Simultaneous quantitative analysis of polyethylene glycol (PEG), PEGylated paclitaxel and paclitaxel in rats by MS/MSALL technique with hybrid quadrupole time-of-flight mass spectrometry

PEGylation is practically one of most important modifications of drugs including small molecules, peptides and proteins, which has been proven to dramatically improve physicochemical properties and pharmacokinetic behavior of the PEGylated drugs. However, it is a challenge currently to quantitatively analyze PEG and PEGylated drugs by various analytical methods, even mass spectrometry because of multiple parent ion distribution of PEG caused by its polydispersity of molecular weight. Here we developed a robust method with MS/MS^ALL technique using electrospray ionization (ESI) source coupled high resolution Quadrupole Time-of-Flight (Q-TOF) mass spectrometry for the quantification of PEG2K-Paclitaxel (PEG-PTX) and its two metabolites, PEG and Paclitaxel (PTX). The analysis was performed on a 300SB-C18 column with acetonitrile and 0.1% formic acid as the mobile phase. Samples were simply prepared by protein precipitation in a small quantity of plasma (50μL). Calibration curve was linear within the range of 50.0-4000ng/mL for PEG and PEG-PTX and 1.0-1000ng/mL for PTX. The intra- and inter-day precisions were 3.2-6.9% and 3.1-6.9% for PEG, 4.1-7.8% and 4.0-9.9% for PEG-PTX, and 3.3-4.8% and 3.1-6.9% for PTX, respectively. The recoveries were greater than 90% with low matrix effects. Afterwards, the newly developed method was successfully applied to support a preclinical pharmacokinetic study in six rats after single intravenous injection of PEG-PTX (51.7mg/kg).