Authors:H. Mahgoub, A. Hanafy, F. Bamane, and A. Radwan
A sensitive and reproducible high-performance liquid chromatographic (HPLC) method for determination of talinolol (TAL) in rat plasma was developed and validated using pindolol (PIN) as an internal standard. Both TAL and PIN were separated on a Zorbax Eclipse XDB C18 column by gradient elution with 0.1% aqueous formic acid and acetonitrile as the mobile phase. Detection was performed using fluorescence measurement at λex 249 nm and λem 333 nm. The method was validated and found to be linear in the range of 10–2000 ng mL−1. The limit of quantification was 10 ng mL−1 based on 100 μL of plasma. The variations for intra- and inter-day precision were less than 10%, and the accuracy values were between 92% and 102.9%. The extraction recoveries were more than 82%. The assay was successfully applied to an in-vivo pharmacokinetic study of TAL in rats that were administered a single oral dose of 10 mg kg−1 TAL. The maximum concentration (Cmax) and the area under the plasma concentration-time curve (AUC0–12) were 0.369 ± 0.024 μg mL−1 and 1.429 ± 0.027 μg h mL−1, respectively. The modulatory effect of apricot juice on P-glycoprotein-related efflux carriers was also investigated. Co-administration of apricot juice resulted in a significant increase of the amount of TAL in plasma (Cmax and AUC0–12 were 0.679 ± 0.021 and 2.357 ± 0.079, respectively; p < 0.05).
Authors:Carlos Florindo, Cinthia Alves Barroco, Inês Silvestre, Vera Damião, João Paulo Gomes, Barbara Spellerberg, Ilda Santos-Sanches, and Maria José Borrego
-iT PicoGreen was added to an equal volume of each supernatant, previously diluted in 1× Tris–EDTA (TE) buffer. After 5 min of incubation at room temperature, in the dark, we proceeded to the fluorescencemeasurement (Fluorimeter – Anthos Zenith 3100) in 96-well
assay reagents on a glass chip followed by fluorescencemeasurements across the gradient. They validated the assay using known BACE1 inhibitors, determining IC 50 values using the flow bioassay and traditional well plate-based assays, demonstrating very