Data for "Evaluation of the bone glycocalyx mechanical properties by AFM nanoindentation"

Pre-processed data obtained by AFM nano-indentation of MLO-A5 pre-osteocyte cells. The data pre-processing consisted in contact point fitting, tip-sample separation correction and drift correction of raw data, all performed in MATLAB (v2016a).The experimental methodology and data processing are described in the author's thesis (Chapter 4).Methods* AFM cantilever preparationSpherical tipped cantilevers were prepared. To increase the possibility of sensing the glycocalyx, softer cantilevers were chosen with nominal spring constant equal to 0.01 N/m (Windsor Scientific) and silica beads of different sizes were tested (D = 1; 2:5; 6 μm, Bangs Laboratories).* AFM set-upA NanoWizard 3 atomic force microscope (JPK Instruments AG) coupled to an Eclipse Ti-S optical inverted microscope (Nikon Instruments) was used for all the experiments.The cells were washed in phosphate buffer solution (PBS) and fresh medium was added. Samples were positioned on the heated sample holder to allow for testing at 37◦C. Single cells were located through the coupled optical microscope and images of cell shape were recorded for morphological analysis. The cantilever was centred over the location of interest and a grid of 5 points spaced 3 μm within each other was set. Force spectroscopy measurements were obtained on the 5-point grid for 3 times to collect a total of 15 data on each location. The relative set point and the approach velocity were set to 10 nN and 4 μm/s respectively.

本数据集为由原子力显微镜（AFM）对MLO-A5前期成骨细胞进行的纳米压痕实验所获得的预处理数据。数据预处理过程包括接触点拟合、尖端与样品分离的校正以及原始数据的漂移校正，所有操作均在MATLAB（v2016a）软件中完成。实验方法及数据处理方法详见作者论文（第四章）。

方法：
* AFM 锋针制备：采用球形尖端锋针，为提高检测糖萼的可能性，选择弹簧常数标称值为0.01 N/m（Windsor Scientific）的较软锋针，并测试了不同尺寸的二氧化硅微球（D = 1；2:5；6 μm，Bangs Laboratories）。
* AFM 设备配置：使用配备有Eclipse Ti-S光学倒置显微镜（Nikon Instruments）的NanoWizard 3原子力显微镜（JPK Instruments AG）进行所有实验。细胞用磷酸盐缓冲溶液（PBS）清洗，并添加新鲜培养基。样品放置在加热样品台上，以便在37◦C下进行测试。通过耦合光学显微镜定位单个细胞，并记录细胞形态图像以进行形态学分析。将锋针置于兴趣点的中心，设置间距为3 μm的5点网格。在5点网格上进行了3次力谱测量，以收集每个位置的15个数据点。相对设定点和接近速度分别设置为10 nN和4 μm/s。