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Droplet-based microfluidic assisted devices have proposed an extensive interest in many applications such as lab-on-a-chip technologies as well as chemical/biological/nanomaterial preparation, chemical engineering, drug delivery, tissue engineering and biosensing. Here, a computational fluid dynamic model was developed for deep understanding of the droplet size and formation in a flow-focusing (FF) microchannel with consideration of the continuous phase (non-Newtonian fluid). The simulations presented an alternative method to achieve insights into this complicated process. In the following for the first time, the role of channel geometry, channel aspect ratio and flow rate ratio on droplet features including the mechanism of droplet formation, diameter/volume of droplet, velocity/amount of droplet formation, and final shape/size of the generated droplets were fully described. These findings could remarkably derive desirable protocols to control droplets characteristics comprising their size and shape in non-Newtonian fluids. Moreover, level set (LS) method was used for scrutinizing the droplet-breaking procedure in the microfluidic FF devices. The results showed that different droplet sizes could be prepared with changing the various parameters, demonstrating many challenges in various applications including lab-on-a-chip, cell encapsulation, drug delivery, tissue engineering, biosensing and bioimaging could be successfully addressed. Marine demosponges of the Verongiida order are considered a gold-mine for bioinspired materials science and marine pharmacology. The aim of this work was to simultaneously isolate selected bromotyrosines and unique chitinous structures from A. aerophoba and to propose these molecules and biomaterials for possible application as antibacterial and antitumor compounds and as ready-to-use scaffolds for cultivation of cardiomyocytes, respectively. Among the extracted bromotyrosines, the attention has been focused on aeroplysinin-1 that showed interesting unexpected growth inhibition properties for some Gram-negative clinical multi-resistant bacterial strains, such as A. baumannii and K. pneumoniae, and on aeroplysinin-1 and on isofistularin-3 for their anti-tumorigenic activity. For both compounds, the effects are cell line dependent, with significant growth inhibition activity on the neuroblastoma cell line SH-SY5Y by aeroplysinin-1 and on breast cancer cell line MCF-7 by isofistularin-3. In this study, we also compared the cultivation of human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) on the A. aerophoba chitinous scaffolds, in comparison to chitin structures that were pre-coated with Geltrex™, an extracellular matrix mimetic which is used to enhance iPSC-CM adhesion. The iPSC-CMs on uncoated and pure chitin structures started contracting 24 h after seeding, with comparable behaviour observed on Geltrex-coated cell culture plates, confirming the biocompatibility of the sponge biomaterial with this cell type. The advantage of A. aerophoba is that this source organism does not need to be collected in large quantities to supply the necessary amount for further pre-clinical studies before chemical synthesis of the active compounds will be available. A preliminary analysis of marine sponge bioeconomy as a perspective direction for application of biomaterials and secondary bioactive metabolites has been finally performed for the first time. Resin-based pit-and-fissure sealants (flowable resin composites) were formulated using bisphenol-A-glycerolatedimethacrylate (Bis-GMA)-triethylene glycol dimethacrylate-(TEGDMA)-diurethanedimethacrylate (UDMA) mixed monomers and multiple fillers, including synthetic strontium fluoride (SrF2) nanoparticles as a fluoride-releasing and antibacterial agent, yttria-stabilized zirconia (YSZ) nanoparticles as an auxiliary filler, and poly-ε-l-lysin (ε-PL) as an auxiliary antibacterial agent. Based on the physical, mechanical and initial antibacterial properties, the formulated nano-sealant containing 5 wt% SrF2, 5 wt% YSZ and 0.5 wt% ε-PL was selected as the optimal specimen and examined for ion release and cytotoxicity. find more The results showed an average release rate of 0.87 μg·cm-2·day-1 in the aqueous medium (pH 6.9) and 1.58 μg·cm-2·day-1 in acidic medium (pH 4.0). The maximum cytotoxicity of 20% toward human bone marrow mesenchymal stem cells (hMSCs) was observed according to the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) cytotoxicity assay and acridine orange staining test. A synergy between SrF2 nanoparticles and ε-PL exhibited a better antibacterial activity in terms of colony reduction compared to the other samples. However, the inclusion of SrF2 and ε-PL caused mechanically weakening of the sealants that was partly compensated by incorporation of YSZ nanoparticles (up to 10 wt%). Stem cells from human exfoliated deciduous teeth (SHED) are considered the best current source of human stem cells due to their ability to differentiate into multiple cell lineages. Dynamic co-culture systems can improve the culture environment, as they provide cells with signaling factors, extracellular matrixes, and cellular shear force, as well as enable the formation of heterotypic clusters. We seeded SHED in 3D silk fibroin porous scaffolds under static and dynamic cultures for 28 days, using the NIH3T3 cultivated medium as an induction agent. Many hepatospheres formed in these porous scaffolds, and cellular viability was shown to continually increase by MTT assays. Hepatic AFP and ALB gene expression, as well as glycogen storage, albumin secretion, and urea synthesis, were greater in cells in the 3D porous scaffold under a dynamic culture than in those cultured under 3D static culture and petri dish conditions. However, the 3D static culture is still superior to the traditional petri dish culture. The NIH3T3 cultivated medium can significantly induce hepatic differentiation of SHED, while the 3D dynamic culture system significantly enhances hepatic differentiation of SHED. This study provides alternative sources of hepatocytes for liver disease treatment.