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This work is to study the relationship between the exposure conditions and the quality of cell imaging with soft X-ray contact microscopy (SXCM). It is a crucial step in the efficient visualization of cell structures. Three different human cell lines: DU145 prostate carcinoma cells, HCC38 breast cancer cells, and Poietics mesenchymal stem cells were used to establish the optimal exposure conditions in SXCM. The image quality depended on the soft X-ray (SXR) absorbed energy and photoresist development conditions. At lower SXR energy (200 or 400 SXR pulses), sharp cell edges, membrane projections, and cell–cell connections were visible. In contrast, higher energy (600 or 800 SXR pulses) allowed observation of the cytoskeleton and the nucleus in a cell type-dependent manner (the influence of cell thickness and internal complexity was noted).

The rheological characterization of soft suspended bodies, such as cells, organoids, or synthetic microstructures, is particularly challenging, even with state-of-the-art methods (e.g. atomic force microscopy, AFM). Providing well-defined boundary conditions...

Atomic force microscopy (AFM) has been used to study the mechanical properties of cells, in particular, malignant cells. Softening of various cancer cells compared to their nonmalignant counterparts has been reported for various cell types. However, in most AFM studies, the pericellular layer was ignored. As was shown, it could substantially change the measured cell rigidity and miss important information on the physical properties of the pericellular layer. Here we take into account the pericellular layer by using the brush model to do the AFM indentation study of bladder epithelial bladder nonmalignant (HCV29) and cancerous (TCCSUP) cells. It allows us to measure not only the quasistatic Young’s modulus of the cell body but also the physical properties of the pericellular layer (the equilibrium length and grafting density). We found that the inner pericellular brush was longer for cancer cells, but its grafting density was similar to that found for nonmalignant cells. The outer brush was much shorter and less dense for cancer cells. Furthermore, we demonstrate a method to convert the obtained physical properties of the pericellular layer into biochemical language better known to the cell biology community. It is done by using heparinase I and neuraminidase enzymatic treatments that remove specific molecular parts of the pericellular layer. The presented here approach can also be used to decipher the molecular composition of not only pericellular but also other molecular layers.