Design of Cationic Lipids with Acetal Linkers: Conformational Preferences,Hydrolytic Stability,and High Drug-Loading Abilities

Lipids are key constituents of numerous biomedical drug delivery technologies. Here, we present the design, synthesis and biophysical characterizations of a library of cationic lipids containing an acetal residue in their linker region. These cationic acetal lipids (CALs) were conveniently prepared through a trans-acetalization protocol from commercially available precursors. NMR studies highlighted the conformational rigidity at the acetal residue and the high hydrolytic stability of these CALs. Fluorescence anisotropy studies revealed that the CAL with a pyridinium headgroup (CAL1) formed highly cohesive vesicular aggregates in water. These structural and self-assembly features of the CAL1 allowed up to 196 % w/w loading of curcumin (Cur) as a representative hydrophobic drug. A reconstitutable formulation of Cur was obtained as a result, which could deliver the drug inside mammalian cells with very high efficiency. The hemocompatibility and cytocompatibility of CAL1 was significantly enhanced by creating a coating of polydopamine (PDA) onto its vesicular assemblies to produce hybrid lipid-polymer nanocapsules. This work demonstrates rapid access to the useful synthetic lipid formulations with high potential in drug and gene delivery applications.     

Impact of Different Gate Dielectric Materials on Analog/RF Performance of Dielectric-Pocket Double Gate-All-Around (DP − DGAA) MOSFETs

Silicon - This paper investigates the performance analysis of Dielectric Pocket (DP)-Double Gate All Around (DGAA) with three different gate dielectric materials and analyzes its performance. The...     

Design framework for dimethyl ether (DME) production from coal and biomass-derived syngas via simulation approach

A comprehensive thermodynamic study was conducted to evaluate the comparative efficacy of methanol and dimethyl ether (DME) synthesis using CO₂ rich syngas feed. The first part of our study included assessing the relative performances of the methanol synthesis system, two step DME synthesis system, and one step DME synthesis system in terms of the CO_x conversion and product yield (methanol/DME) based on the Gibbs free energy minimization approach. The wide range of composition of CO₂-enriched syngas feed produced by the coal and biomass gasification was simulated using Aspen Plus and the following evaluation parameters were analyzed for a broad parameter range: reaction temperature (180–280°C), reaction pressure (10–80 bar), stoichiometry number (SN) (0–11), and CO₂/(CO₂ + CO) molar feed ratio (0–1) for isothermal as well as adiabatic conditions. Based on the equilibrium yield, one-step DME synthesis was discovered as the most viable process to utilize the co-gasification derived syngas effectively. In the second part of our study, the overall process efficiency was inspected through the process design of 1 tonnes per day (TPD) DME plant inclusive of heat integration, resulting in significant CO₂ abatement and DME production with high product purity and minimum energy consumption. Consequently, one-step DME production via CO₂-enriched syngas obtained through the coal or biomass gasification process is identified as the leading technology based on energy utilization and CO₂ abatement.     

Impact of Temperature Variation on Analog,Hot-Carrier Injection and Linearity Parameters of Nanotube Junctionless Double-Gate-All-Around (NJL-DGAA) MOSFETs

Silicon - Silicon-based Nanotube Junction-less Double-Gate-All-Around (NJL-DGAA) MOSFETs has become a promising solution to high-speed ULSI chip design. However, the change in surrounding...