Penicillin streptomycin mixture pen strep

Samples were also characterized by means of infrared spectroscopy. FTIR spectra were carried out using a Shimadzu Prestige-21 spectrometer in the range 400-4000 cm -1 , using KBr pellets and resolution of 4 cm -1 .
MTT. A375 human melanoma cells were seeded onto a 96well culture plate at a cellular density of 1×10 4 cells/well and attached to the bottom of the well overnight. After 24 hours, 100 μL of new medium containing Dulbecco's Modified Eagle's Medium (DMEM; Gibco BRL, Invitrogen, Carlsbad, CA, USA) and 50 and 150 µg/ml of the tested substances (dissolved in dimethyl sulfoxide -DMSO; Sigma-Aldrich Company), were added and incubated for 72 h; the medium was supplemented with 10% foetal calf serum (FCS; PromoCell, Heidelberg, Germany) and 1% Penicillin/Streptomycin mixture (Pen/Strep, 10,000 IU/ml; PromoCell, Heidelberg, Germany). The cells were then assayed by the addition of 10 μL of 5 mg/mL MTT solution from the MTT-based in vitro toxicology assay kit (Tox-1; Sigma-Aldrich). The intact mitochondrial reductase converted and precipitated MTT as blue crystals during a 3 h contact period. The precipitated crystals were dissolved in 100 μL of lysis solution (Sigma-Aldrich). The reduced MTT was spectrophotometrically analyzed at 590 and 655 nm, using a microplate reader (Bio-Rad, Hercules, CA, USA). Stock solutions of the tested substances (10 mg/ml) were prepared in DMSO.