The Interaction between DNA and Three Intercalating Anthracyclines Using Electrochemical DNA Nanobiosensor Based on Metal Nanoparticles Modified Screen-Printed Electrode

The screen-printed electrodes have gained increasing importance due to their advantages, such as robustness, portability, and easy handling. The manuscript presents the investigation of the interaction between double-strand deoxyribonucleic acid (dsDNA) and three anthracyclines: epirubicin (EPI), idarubicin (IDA), and doxorubicin (DOX) by differential pulse voltammetry on metal nanoparticles modified by screen-printed electrodes. In order to investigate the interaction, the voltammetric signals of dsDNA electroactive bases were used as an indicator. The effect of various metal nanomaterials on the signals of guanine and adenine was evaluated. Moreover, dsDNA/PtNPs/AgNPs/SPE (platinum nanoparticles/silver nanoparticles/screen-printed electrodes) was designed for anthracyclines–dsDNA interaction studies since the layer-by-layer modification strategy of metal nanoparticles increases the surface area. Using the signal of multi-layer calf thymus (ct)-dsDNA, the within-day reproducibility results (RSD%) for guanine and adenine peak currents were found as 0.58% and 0.73%, respectively, and the between-day reproducibility results (RSD%) for guanine and adenine peak currents were found as 1.04% and 1.26%, respectively. The effect of binding time and concentration of three anthracyclines on voltammetric signals of dsDNA bases were also evaluated. The response was examined in the range of 0.3–1.3 ppm EPI, 0.1–1.0 ppm IDA and DOX concentration on dsDNA/PtNPs/AgNPs/SPE. Electrochemical studies proposed that the interaction mechanism between three anthracyclines and dsDNA was an intercalation mode

Quantification of FGFR4 inhibitor BLU-554 in mouse plasma and tissue homogenates using liquid chromatography-tandem mass spectrometry

BLU-554 is a potent, highly selective oral FGFR4 inhibitor. A bioanalytical assay for quantification of BLU-554 in mouse plasma and six tissue homogenates (brain, kidney, liver, lung, small intestine, and spleen) was developed and validated using liquid chromatography with tandem mass spectrometric detection and with erlotinib as internal standard. After protein precipitation with acetonitrile in a 96-well format and separation on an XBridge® Peptide BEH C18 column by gradient elution using 0.2% (v/v) ammonium hydroxide (in water) and methanol, analytes were ionized by positive electrospray and monitored in the selected reaction monitoring mode by triple quadrupole mass spectrometry. The assay was validated in a 1–1000 ng/ml concentration range using calibration in mouse plasma. Precisions (intra–day and inter–day) were in the range 2.8–10.1% and accuracies were in between 88.5 and 96.6% for all levels in all matrices. The assay was successfully applied for a pilot pharmacokinetic and tissue distribution study in wild-type mice

Quantification of FGFR4 inhibitor BLU-554 in mouse plasma and tissue homogenates using liquid chromatography-tandem mass spectrometry

BLU-554 is a potent, highly selective oral FGFR4 inhibitor. A bioanalytical assay for quantification of BLU-554 in mouse plasma and six tissue homogenates (brain, kidney, liver, lung, small intestine, and spleen) was developed and validated using liquid chromatography with tandem mass spectrometric detection and with erlotinib as internal standard. After protein precipitation with acetonitrile in a 96-well format and separation on an XBridge® Peptide BEH C18 column by gradient elution using 0.2% (v/v) ammonium hydroxide (in water) and methanol, analytes were ionized by positive electrospray and monitored in the selected reaction monitoring mode by triple quadrupole mass spectrometry. The assay was validated in a 1–1000 ng/ml concentration range using calibration in mouse plasma. Precisions (intra–day and inter–day) were in the range 2.8–10.1% and accuracies were in between 88.5 and 96.6% for all levels in all matrices. The assay was successfully applied for a pilot pharmacokinetic and tissue distribution study in wild-type mice