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Organoids are self-organizing, three-dimensional structures that replicate the main features of an organ. It is a fast-evolving area of research in regenerative medicine and cell biology. While the primary or stem cells are adapted for most of the organoid systems, Human Embryonic Kidney (HEK) 293T cells have been used in specialized applications within organoid systems when genetic manipulation is necessary. Unfortunately, HEK293T cells often suffer from loose adherence, which limits their applications in organoid formation. To improve cellular adhesion and proliferation, and to provide insights into the pathways involved in adhesion, HEK293T cells were cultured on a glass substrate sputtered with indium tin oxide (ITO) that is covered with a self-assembled monolayer (SAM) of 3-(mercaptopropyl) trimethoxysilane (MPS) (hereafter known as ITO-MPS SAM-coated substrate), a SAM of 3-(aminopropyl) triethoxysilane (APTES), and a SAM of 1-octadecanethiol (ODT). The ITO-MPS SAM scaffold yielded the most promising results, based on cell proliferation using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assays. Nuclear Magnetic Resonance (NMR) spectroscopy was used to analyze the metabolomics present in the media with and without ITO-MPS-SAM coated substrates for a period of 120 h. The findings from the MTT assays demonstrate improved cell adhesion and proliferation on the ITO-MPS SAM-scaffold. The confocal microscopy images are consistent with these findings and provide a visual confirmation of the enhanced cellular environment. The metabolomic analysis yielded twenty-six metabolites, including sixteen adhesion promoters and modulators. These findings provide valuable insights into optimizing substrate conditions for improving cell adhesion and proliferation in HEK293T cells, potentially enhancing 3D cell culture and organoid research. The study also highlights novel metabolomic changes associated with improved cellular adhesion, contributing to the broader field of regenerative medicine and tissue engineering. 

In recent years, rising environmental concerns have led to the focus on some of the innovative alternative technologies to produce clean burning fuels. Fischer–Tropsch (FT) synthesis is one of the alternative chemical processes to produce synthetic fuels, which has a current research focus on reactor and catalyst improvements. In this work, a cobalt nanofilm (~4.5 nm), deposited by the atomic layer deposition (ALD) technique in a silicon microchannel microreactor (2.4 cm long × 50 µm wide × 100 µm deep), was used as a catalyst for atmospheric Fischer–Tropsch (FT) synthesis. The catalyst film was characterized by XPS, TEM-EDX, and AFM studies. The data from AFM and TEM clearly showed the presence of polygranular cobalt species on the silicon wafer. The XPS studies of as-deposited and reduced cobalt nanofilm in silicon microchannels showed a shift on the binding energies of Co 2p spin splits and confirmed the presence of cobalt in the Co0 chemical state for FT synthesis. The FT studies using the microchannel microreactor were carried out at two different temperatures, 240 °C and 220 °C, with a syngas (H2:CO) molar ratio of 2:1. The highest CO conversion of 74% was observed at 220 °C with the distribution of C1–C4 hydrocarbons. The results showed no significant selectivity towards butane at the higher temperature, 240 °C. The deactivation studies were performed at 220 °C for 60 h. The catalyst exhibited long-term stability, with only ~13% drop in the CO conversion at the end of 60 h. The deactivated cobalt film in the microchannels was investigated by XPS, showing a weak carbon peak in the XPS spectra.