Nucleocounter nc 200 automatic cell counter

In vitro studies were performed using two models: the Normal Human Dermal Fibroblast (NHDF) cell line (Lonza Group, Basel, Switzerland) and L929 cells, (Sigma-Aldrich, Merck Group, Darmstadt, Germany) (The European Collection of Authenticated Cell Cultures-ECACC). Cells were cultured under standard conditions at 37 °C, 5% CO₂, 95% humidity, in a CO₂ incubator. Cells were always cultured for a minimum of 2 weeks after thawing before starting a series of experiments. Cell cultures were passaged with trypsin/EDTA solution. Cells were counted using a NucleoCounter^® NC-200 automatic cell counter (ChemoMetec A/S, Allerod, Denmark). Cells were cultured in Dulbecco’s modified Eagle medium (DMEM), 10% fetal bovine serum (FBS), penicillin (10,000 U/mL), streptomycin (10 mg/mL), and L-glutamine (200 mM). All culture reagents were purchased from Biological Industries (Biological Industries, Kibbutz Beit-Haemek, Israel).

Two cell types were used in the study: primary gingival fibroblasts; normal, human, adult (HGF) from ATCC (Manassas, VA, USA); and CHO cells purchased from Sigma-Aldrich (The European Collection of Authenticated Cell Cultures—ECACC). Cell cultures were carried out in an incubator at 37 °C, in a 5% CO₂ atmosphere, at 95% humidity. Cells, after thawing, were cultured for at least 2 weeks prior to testing. During culturing, confluence measurement was performed using a Juli Br microscope (NanoEntek, Seoul, Republic of Korea). Cell cultures were passaged once a week with trypsin/EDTA solution. Cells for the assay were counted using a NucleoCounter^® NC-200 automatic cell counter (ChemoMetec A/S, Allerod, Denmark). Cells were cultured in Dulbecco’s modified eagle medium (DMEM) without phenol red or F-12K medium (Kaighn’s modification of Ham’s F-12 medium) supplemented with 10% fetal bovine serum (FBS), antibiotics, and L-glutamine (200 mM). Culture reagents were purchased from Biological Industries (Beit-Haemek, Israel). Detailed methodology for the assessment of cell vitality is presented by Hadzik et al. concerning experimental implant surfaces [16 (link)].