Uv vis spectrophotometer 8453 uv vis supplies

The release kinetics of Cv from the chitosan particles were analyzed in phosphate buffered saline (PBS), the same used for the biological assays. The pellet of free and loaded nanoparticles was resuspended in 0.8 mL of PBS. The mixture was then left in gentle agitation for the required time at 25 °C. At different intervals of incubation time (0 h, 24 h, 48 h, 72 h, and 96 h), 100 µL of the sample was taken, centrifuged at 9000 rpm for 5 min at 25 °C. An equal volume of PBS was then added to the solution to restore the original volume. The amount of carvacrol released into the supernatant was calculated by UV spectrophotometer considering the maximum absorption wavelength of carvacrol (278 nm). The spectrum and concentrations of carvacrol were determined by UV-Vis Spectrophotometer (8453 UV-Vis Supplies, Agilent Technologies, Santa Clara, CA, USA) by diluting the compound in ethanol. The calculated molar extinction coefficient for carvacrol in ethanol was 2.650 M⁻¹ cm⁻¹.

Tissue homogenization and sonication were carried out by means of Wheaton^® 903475 Overhead Stirrer apparatus (Wheaton, Millville, NJ, USA) and Branson sonifer 450 (Branson Ultrasonics, Danbury, CT, USA), respectively. Total protein concentration was determined in duplicate by Bradford assay (Bio-Rad Laboratories, Hercules, CA, USA) and UV-Vis spectrophotometer (8453 UV-Vis Supplies, Agilent Technologies, Waldbronn, Germany) detector using BSA as the protein of reference. For sample centrifugation, thermostated centrifuge SL16 R (Thermo Fisher Scientific, Langenselbold, Germany) and Mini Spin (Eppendorf AG, Germany) were used as specified for sample treatment. HPLC-ESI-MS/MS analyses were performed on UltiMate 3000 RSLCnano System (Dionex, Sunnyvale, CA, USA) coupled to Orbitrap Elite MS detector with ESI or EASY-Spray nanoESI sources (Thermo Fisher Scientific), as specified elsewhere.