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Engineered Lipid Coronas for Gold Nanoparticle-Based Bioorthogonal Catalysis
No full textBioorthogonal catalysis provides a powerful biomedical tool for controlled ‘turn-on’ activation of prodrugs and pro-dyes. Gold-based catalysts are highly selective and nontoxic; however, they are susceptible to deactivation by serum proteins and biogenic thiols. We present here a strategy that protects gold nanoparticle (AuNP) catalysts with a lipid corona, enabling bioorthogonal catalysis in biological environments. The modular nature of the lipid corona enables tuning of the surface charge, membrane fluidity, and PEG content. The stability and activity of these lipid-coated AuNPs was demonstrated by successfully converting inactive propargylated doxorubicin to the active drug in cancer cells
Imprints of extra dimensions in eccentric EMRI gravitational waveforms
No full textStudies regarding extra-dimensions have been of great interest in modern theoretical physics, including their observational consequences from future gravitational wave (GW) observatories. In this direction, extreme mass-ratio inspirals (EMRI), attracting considerable interest in GW astronomy and fundamental physics, can potentially provide a useful platform for the search of extra dimensions. In this paper, we examine a rotating braneworld black hole in the context of equatorial eccentric EMRI and attempt to provide an order of magnitude analysis for the extra-dimensional parameter termed "tidal charge". We estimate GW fluxes for the dominant mode and determine the impact of the tidal charge parameter on the orbital evolution. We further evaluate the prospects of detecting such a parameter through mismatch computation. We observe a significant enhancement in the mismatch as the value of orbital eccentricity or tidal charge parameter increases; the phenomenon becomes more obvious for rapidly rotating massive black holes. Thus, the study suggests that eccentric EMRI can potentially probe the existence of extra dimensions with future low-frequency detectors such as the Laser Interferometer Space Antenna (LISA)
Recent advances in clinical applications of targeted nanomaterials
No full textTargeted nanomaterials are at the forefront of advancements in nanomedicine due to their unique and versatile properties. These include nanoscale size, shape, surface chemistry, mechanical flexibility, fluorescence, optical behaviour, magnetic, and electronic characteristics as well as biocompatibility and biodegradability. These attributes enable their application across diverse fields such as drug delivery, bioimaging, sensing, disease diagnostics, tissue engineering, cosmetics, and electronics. This review explores the fundamental characteristics of nanomaterials and emphasize their importance into clinical applications. It further delves into methodologies for nanoparticles programming alongside discussions on clinical trials and case studies. We discussed some of promising nanomaterials such as polymeric nanoparticles, carbon-based nanoparticles and metallic nanoparticles with their role in biomedical applications. The review underscores significant advancements in translating nanomaterials into clinical applications and highlight the potential of these innovative approaches in revolutionizing the medical field
Programmable soft DNA hydrogels stimulate cellular endocytic pathways and proliferation
No full textHydrogels are pivotal in tissue engineering, regenerative medicine, and drug delivery applications. Existing hydrogel platforms are not easily customizable and often lack precise programmability, making them less suited for 3D tissue culture and programming of cells. DNA molecules stand out among other promising biomaterials due to their unparalleled precision, programmability, and customization. In this study, we introduced a palette of novel cellular scaffolding platforms made of pure DNA-based hydrogel systems while improving the shortcomings of the existing platforms. We showed a quick and easy one step synthesis of DNA hydrogels using thermal annealing based on sequence specific hybridization strategy. We also demonstrated the formation of multi-armed branched supramolecular scaffolds with custom mechanical stiffness, porosity, and network density by increasing or decreasing the number of branching arms. These mechanically tuneable DNA hydrogels proved to be a suitable suitable platform for modulating the physiological processes of retinal pigment epithelial cells (RPE1). In-vitro studies showed dynamic changes at multiple levels, ranging from a change in morphology to protein expression patterns, enhanced membrane traffic, and proliferation. The soft DNA hydrogels explored here are mechanically compliant and pliable, thus excellently suited for applications in cellular programming and reprogramming. This research lays the groundwork for developing a DNA hydrogel system with a higher dynamic range of stiffness, which will open exciting avenues for tissue engineering and beyond
Characterisation and experimental study of micro-second laser-induced surface colourisation of Ti6Al4V
No full textExperimental Investigation on the Effect of Cr and Mn in High Temperature Oxidation of Cantor Alloy
No full textHigh entropy alloys have emerged recently as promising candidates for high-temperature applications. This study explores the detailed oxidation behavior of CoCrFeMnNi alloy by using a combination of in-situ, short-duration and long-duration high-temperature exposure up to 1000 ⁰C. The study reveals Cr and Mn played a significant role in the oxidation/passivation of the alloy. It was found that Cr enhanced the oxidation resistance, especially by limiting oxygen diffusion and was quite effective up to 600 ⁰C. However, at higher temperatures, Mn continuously diffuses towards the surface and forms a poorly adherering oxide scale. Study on CoCrFeNi and CoFeMnNi alloys to investigate the roles of Cr and Mn individually revealed that under similar conditions, CoCrFeNi had a relatively continuous and less spalled oxide layer with better adherence to the alloy compared to cantor alloy. However, compared to Cr-containing alloys, the CoFeMnNi alloy did not have a continuous, well-adhering, non-protective oxide layer making the alloy prone to severe and faster oxidation. Same was apparent from significant internal oxidation, the appearance of massive cracks, and voids. Before and after the oxidation, CoCrFeMnNi and CoCrFeNi were single-phase fcc structures while CoFeMnNi decomposed into a two-phase alloy due to significant uptake of oxygen. Prolonged oxidation and molten-state studies revealed that the oxidation behaviour of HEAs is a thermodynamic-driven process, and CoCrFeMnNi is expected to gradually lose Mn to surface oxide followed by migration of Co, Ni and Fe, which otherwise hardly migrated or participated in the oxidation process. High-temperature heat treatment in vacuum confirmed that the migration to the surface was driven by its oxidation at the surface
How individual vs shared coordination governs the degree of correlation in rotational vs residence times in a high-viscosity lithium electrolyte
No full textCommercially used carbonate-based electrolytes in lithium-ion batteries are susceptible to many challenges, including flammability, volatility, and lower thermal stability. Solvated ionic liquids of LiTFSI salt (lithium bis(trifluoromethylsulfonyl)-amide) and glyme-based solvents are potential alternative candidates for commonly used electrolytes. We perform classical molecular dynamics (MD) simulations study the effect of concentration and temperature on the translational and rotational dynamics. The radial distribution function shows stronger coordination of Li^+ ions with tetraglyme(G4), as shown in earlier studies, and forms a stable [Li(G4)]^+ cation complex. The self-diffusion coefficients are lower than the values experimentally observed but show better improvement over other classical force fields. An increase in the salt concentrations leads to a higher viscosity of the system and reduces the overall ionic mobility of Li^{+} ions. Diluting the system with a larger number of glyme molecules leads to shorter rotational relaxation times for both TFSI and tetraglyme. Ion-residence times show that Li^+ ions form stable and long-lasting complexes with G4 molecules than TFSI anions. The residence time of [Li(G4)]^+ complex increases at higher salt concentrations due to the availability of fewer G4 molecules to coordinate with a Li^+ ion. G4 is also seen to form polydentate complexes with Li^+ without a shared coordination, allowing rotation without breaking coordination, unlike TFSI, which requires coordination disruption for rotation. This distinction explains the poor correlation between rotation and residence time for G4 and the strong correlation for TFSI