A Supramolecular Photosensitizer System Based on Nano-Cu/ZIF-8 Capped with Water-Soluble Pillar[6]arene and Methylene Blue Host-Guest Complexations.

Photodynamic therapy (PDT) as a safe, non-invasive modality for cancer therapy, in which the low oxygen and high glutathione in the tumor microenvironment reduces therapeutic efficiency. In order to overcome these problems, we prepared a supramolecular photosensitive system of O2-Cu/ZIF-8@ZIF-8@WP6-MB (OCZWM), which was loaded with oxygen to increase the oxygen concentration in the tumor microenvironment, and the Cu2+ in the system reacted with glutathione (GSH) to reduce the GSH concentration to generate Cu+. It is worth noting that the generated Cu+ can produce the Fenton reaction, thus realizing the combination therapy of PDT and chemodynamic therapy (CDT) to achieve the purpose of significantly improving the anti-cancer efficiency.

Development of a novel and quick UPLC-MS/MS method for the pharmacokinetic analysis of duvelisib in beagle dogs.

Duvelisib, a new oral phosphoinositide-3-kinase (PI3K)-δ and PI3K-γ inhibitor, was recently approved in the USA as the therapeutic drug for patients with the diseases of relapsed or refractory chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). In the present study of our research, a quick and simple bioanalytical method based on ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) technique was fully explored and established for the quantification of plasma duvelisib concentrations from beagle dog in which gilteritinib was used as the internal standard (IS). After a simple and quick protein precipitation treated with acetonitrile, the chromatographic separation of the analyte was carried out on an Acquity BEH C18 column (2.1 mm × 50 mm, 1.7 µm) conducted in a gradient elution procedure where acetonitrile (solvent A) and 0.1 % formic acid in water (solvent B) consisted as the mobile phase. The measurements of the analyte and IS were explored using a XEVO TQS triple quadrupole tandem mass spectrometer, which was comprised with electrospray ionization (ESI) source in positive ion mode. Selected reaction monitoring (SRM) mode was employed to detect the parent-to-daughter ion transitions as follows: m/z 416.88 → 281.88 for duvelisib, and m/z 553.09 → 436.01 for IS, respectively. The assay was successfully established in the calibration range from 0.5 to 3000 ng/mL for duvelisib, where the lower limit of quantification (LLOQ) was set at 0.5 ng/mL. The precisions of intra-day and inter-day for duvelisib were all below 12.6 %, and the accuracies were from -2.5% to 14.1%. Both matrix effect and mean recovery of the analyte and IS were all acceptable, and the analyte was stable during the assay and storage in dog plasma samples. The novel established bioanalytical method based on UPLC-MS/MS technique was effectively employed to the investigation of the pharmacokinetic profile of duvelisib in beagle dogs following a 1.34 mg/kg single dose of oral administration.

Liquid chromatography-tandem mass spectrometric method for the quantification of eliglustat in rat plasma and the application in a pre-clinical study.

Eliglustat is an oral substrate reduction therapy drug and has been approved as a first-line treatment for adults with Gaucher disease type 1 (GD 1). In the present study, we aimed to develop and establish an accurate and simple ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the measurement of eliglustat concentration in rat plasma. The goal of chromatographic separation of eliglustat and the internal standard (bosutinib) was finished on an Acquity BEH C18 (2.1 mm × 50 mm, 1.7 µm) column. Acetonitrile and 0.1% formic acid in water were employed as the mobile phase in a mode of gradient elution with the 0.40 mL/min flow rate. The detection was carried out on a XEVO TQ-S triple quadrupole tandem mass spectrometer coupled with electrospray ionization (ESI) interface in the positive-ion mode. Multiple reaction monitoring (MRM) was used to monitor the precursor-to-product ion transitions of m/z 405.4 → 84.1 for eliglustat and m/z 530.2 → 141.2 for bosutinib (IS), respectively. It was found that the linearity of the method in the range of 1-500 ng/mL was good for eliglustat. The values of intra- and inter-day accuracy and precision were all within the acceptance limits, and no matrix effect was found in this method. The current developed method was further performed to support in vivo pharmacokinetic study of eliglustat after oral treatment with 10 mg/kg eliglustat to rats.

In vivo Pharmacokinetic Drug-Drug Interaction Studies Between Fedratinib and Antifungal Agents Based on a Newly Developed and Validated UPLC/MS-MS Method.

In the current research experiment, a sensitive, precise and rapid bioanalytical approach involving the detection of fedratinib concentrations in rat plasma by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) technique was optimized and established, and it was employed to describe the changes of fedratinib concentrations after oral treatment with various antifungal drugs (isavuconazole, posaconazole, fluconazole and itraconazole). An Acquity UPLC BEH reverse-phase C18 column (2.1 mm × 50 mm, 1.7 µm) was used for chromatographic separation of fedratinib and bosutinib (as internal standard (IS) in our study) under a linear gradient elution of the mobile phase, which was composed of solution A (acetonitrile) and solution B (water with 0.1% formic acid), along with 0.40 ml/min flow rate. The analyte and internal standard were measured with electrospray ion source in positive ion mode on a XEVO TQS triple quadrupole tandem mass spectrometer. The newly developed UPLC-MS/MS assay displayed enough linearity within the concentration range of 0.5-500 ng/ml for calibration curve. The intra- and inter-day of precision and accuracy were evaluated and validated to meet the requirements for the guidelines of bioanalytical assay. In addition, the findings of matrix effect, recovery, and stability were all within the acceptable limits. The new UPLC-MS/MS method was also successfully applied to characterize the pharmacokinetic changes of fedratinib in rats in the present of different antifungal drugs (such as isavuconazole, posaconazole, fluconazole and itraconazole). It turned out that fluconazole resulted in a prominent inhibitory effect on fedratinib metabolism in rats, followed by treatment with itraconazole and isavuconazole. Therefore, the toxicity of fedratinib should be avoided when the concurrent use of fedratinib with CYP3A4 inhibitors may occur.

Effects of capsicine on rat cytochrome P450 isoforms CYP1A2, CYP2C19, and CYP3A4.

Due to the frequent consumption of capsaicin (CAP) and its current therapeutic application, the correct assessment of this compound is important from a public health standpoint. The purpose of this study was to find out whether CAP affects rat cytochrome P450 (CYP) enzymes (CYP1A2, CYP2C19, and CYP3A4) by using cocktail probe drugs in vivo. A cocktail solution at a dose of 5 mL/kg, which contained phenacetin (15 mg/kg), omeprazole (15 mg/kg), and midazolam (10 mg/kg), was given orally to rats treated for 7 d with oral administration of CAP. Blood samples were collected at a series of time-points and the concentrations of probe drugs in plasma were determined by HPLC-MS. The results showed that treatment with multiple doses of CAP had no significant effect on rat CYP1A2. However, CAP had a significant inhibitory effect on CYP2C19 and an inductive effect on CYP3A4. Therefore, caution is needed when CAP is co-administered with some CYP substrates clinically because of potential drug-CAP interactions.

A novel ionic liquid stabilized molecularly imprinted optosensing material based on quantum dots and graphene oxide for specific recognition of vitamin E.

This work prepared a novel ionic liquid stabilized molecularly imprinted optosensing material based on quantum dots (QDs) and graphene oxide (GO) composites using a one-step polymerization for highly selective and sensitive specific recognition of vitamin E (VE). Here, GO was first introduced to the molecularly imprinted polymer (MIP) because of its ultra-high specific surface area which increases the rate of mass-transfer relative to that of traditional bulk MIP. The ionic liquid was used to provide the desired surface binding groups between the QDs and the GO, but also to improve their fluorescence stability by virtue of its high thermal and chemical stability. Under optimal conditions, the relative fluorescence intensity of MIP decreased linearly with the increasing concentration of VE in the range of 2.30×10(-2)-9.20×10(2)µM with a detection limit of 3.5nM and the precision for five replicate detections of 92µM VE was 1.67% (relative standard deviation). At three concentration levels, the recoveries for two samples achieved were 93.00-100.14% and 92.00-102.00%, respectively.