Confocal microscopy is an essential technique in the field of life sciences, commonly used to study molecules in a variety of preparations, ranging from cells and tissues to entire organisms. In the field of neuroscience, it is a widely utilized tool for both anatomical-structural and functional studies. However, a lesser-known application of this microscopy method is confocal reflectance microscopy, which involves image acquisition based on reflected light from the sample. In this study, we present the use of spectral confocal reflectance microscopy (SCoRe) to explore multiple structures in the rat brain, without the use of any dyes or immunolabeling. Our results demonstrate that this technique allows for the distinction between different brain structures with high spatial resolution, enabling the observation of fibers in the cerebral cortex, corpus callosum, hippocampus, cerebellum, and other regions. These findings highlight the ability of SCoRe to provide detailed anatomical insights that are comparable to those obtained through conventional methods. Additionally, we have shown that SCoRe is compatible with samples prepared using traditional techniques, such as histochemical staining and immunofluorescence. This research emphasizes the value of SCoRe as a cost-effective and label-free method for high-resolution brain imaging, which can improve neuroscience studies and reduce long-term expenses.

Fused deposition modeling (FDM) is an emerging trend for producing nerve guidance conduits (NGCs). This technique allows distinct designs and dimensions to mimic peripheral nerve architecture and promote nerve regeneration. In this study, commercially available TPU 90A and 95A filaments were used for the fabrication of hollow simple wall (non-porous), grooved and gyroid multichannel conduits. The segmented polyurethanes were identified as PBA-MDI-BO-based polyurethanes by ¹H NMR, FTIR and Raman spectroscopy. Thermal analyses, such as DSC and TGA, demonstrated that both TPUs possess sufficient thermal stability to be processed safely under the printing conditions employed. Tensile mechanical tests accounted for their differences in hard segment content in agreement with the Shore A hardness. The measured elastic modulus, in particular, was within a range that may be advantageous for peripheral nerve repair. The gyroid multichannel design showed enhanced resistance to radial compression and highly interconnected internal structure that supported primary neural cell viability and preserved cellular functionality. Therefore, polyurethane-based nerve guidance conduits can be manufactured by FDM, rendering high printability, favorable mechanical performance without compromising biocompatibility.