Alignment and patterning of neurons have great importance in some research fields, especially for regenerative medicine and for the formation of artificial neural networks. Alignment of neurons on quartz grooves and parylene cues on quartz substrate was evaluated in this work. The neurons’ alignment on quartz grooves is considered to be topographical alignment, while the neurons’ alignment on parylene cues on quartz substrate is considered to be chemical alignment. Both quartz grooves’ and parylene cues’ widths were fabricated in a range from 2 µm to 8 µm; quartz grooves’ heights were in a range from 0.25 µm to 4 µm, while parylene cues’ heights were only 0.25 µm. Neurons were dissociated hippocampal neurons from rat E18. Neurons were cultivated on test substrates for 7 days before alignment evaluation. As expected, neurons aligned according to the direction of grooves and cues; however, transversal growth direction was also observed with much smaller tendency. Chemical alignment was found to be more effective than topographical alignment. If parylene cues are thin and distanced enough, then neurons have a tendency to follow the direction of individual parylene cues; however, neurons on quartz grooves have a tendency just to follow a preferable direction than individual quartz grooves.

Nanoparticles have become popular in life sciences in the last few years. They have been produced in many variants and have recently been used in both biological experiments and in clinical applications. Due to concerns over nanomaterial risks, there has been a dramatic increase in investigations focused on safety research. The aim of this paper is to present the advanced testing of rhodamine-derived superparamagnetic maghemite nanoparticles (SAMN-R), which are used for their nontoxicity, biocompatibility, biodegradability, and magnetic properties. Recent results were expanded upon from the basic cytotoxic tests to evaluate cell proliferation and migration potential. Two cell types were used for the cell proliferation and tracking study: mouse embryonic fibroblast cells (3T3) and human mesenchymal stem cells (hMSCs). Advanced microscopic methods allowed for the precise quantification of the function of both cell types. This study has demonstrated that a dose of nanoparticles lower than 20 µg·cm⁻² per area of the dish does not negatively affect the cells’ morphology, migration, cytoskeletal function, proliferation, potential for wound healing, and single-cell migration in comparison to standard CellTracker™ Green CMFDA (5-chloromethylfluorescein diacetate). A higher dose of nanoparticles could be a potential risk for cytoskeletal folding and detachment of the cells from the solid extracellular matrix.