Safe lock tubes 1.5 ml

The peripheral blood samples (6 mL) obtained from nine prostate cancer patients before the first fraction of their treatment were drawn in heparinized tubes, and informed consent was obtained for each donor. The study was approved by the institutional Ethics Committee of the National and Kapodistrian University of Athens. Blood samples were transferred from the heparinized tubes to the Eppendorf safe-lock tubes 1.5 mL (colorless) and were located in a dedicated recess into a solid plate phantom. The same procedure was followed for subpopulations derived from the PC3 human prostate cancer cell line that was karyotypically tested. PC3 cell line was used in this study since it represents a good preclinical model of prostate tumor tissues.

In order to evaluate a possible variation in skin hydration during the study, the content of NMFs was measured, as NMFs are hydrophilic markers of stratum corneum [28 (link)]. Skin surface samples were taken for NMFs analysis on D0, D0 + 4 h, D7, D14 and D24 by rubbing a 5-cm line on the skin with two swabs (Dryswab^® MWE, Medical Wire & Equipment, Wiltshire, UK) previously soaked in an aqueous non-ionic surfactant solution (QIMA, Labège, France—proprietary method), using a standardised, previously validated, sampling technique (unpublished data). The swab heads were then removed, placed in dry Eppendorf tubes (Safe-Lock Tubes 1.5 mL, Eppendorf AG, Hamburg, Germany) and frozen at −20 °C until analysis.
NMFs of interest (urocanic acid (cis/trans-UCA), pyrrolidone carboxylic acid (PCA) and serine were extracted using an aqueous solution, then analysed by a LC/MS system (UltiMate 3000 liquid chromatography system (ThermoScientific, Sunnyvale, CA, USA) coupled with a MSQ Plus Mass detector (ThermoScientific, Sunnyvale, CA, USA). Results are expressed in µg per sample.