02207nas a2200157   4500008004100000022001400041245014700055210006900202260000900271300001600280490000700296520156900303100002601872700002301898856012801921       2021                        eng d  a2040-336400aImplication of adsorption preferences of ions and surfactants on the shape control of gold nanoparticles: a microscopic, atomistic perspective0 aImplication of adsorption preferences of ions and surfactants on  cDEC   a19549-195600 v133 aShape modulation of nanoparticles is crucial for their tailored applications; however, it depends on surfactants, ions, reactants, and other additives present in the growth solution. Here we dissect the role of surfactants, their counterions (halide ions), silver ions, and gold reactant in gold nanoparticle anisotropic growth using polarizable surfaces and nanoseed molecular dynamics simulation models. Our planar surface models predict a 14%-16% increment in cetyltrimethylammonium bromide (CTAB) coverage on Au(111) and Au(100) due to the surface polarization effect. The CTAB micelle adsorbs compactly similar to that observed on non-polarizable surfaces. The cetyltrimethylammonium chloride (CTAC) micelle remains in solution leaving the polarizable gold surfaces unprotected, similar to that observed with the non-polarizable surfaces, which favors isotropic growth. The cetyltrimethylammonium iodide (CTAI) micelle adsorbs with higher surface densities than CTAB on all the surfaces. The surface polarizable penta-twinned nanoseed model predicts the total surface coverage of the cetyltrimethylammonium cation (CTA(+)), Br- and Ag+ to be around two times higher on the side as compared to the tip of the nanoseed, leading to a 2.6 times higher initial rate of adsorption of AuCl2- on the tip than on the side. Predicted CTA(+) surface densities on the tip and the side of the nanoseed are consistent with experimental results. Our simulations explain the growth mechanism of anisotropic nanoparticles and the microscopic origin of their controlled shapes.1 aMeena, Santosh, Kumar1 aMeena, Chandrakala  uhttps://library.ncl.res.in/content/implication-adsorption-preferences-ions-and-surfactants-shape-control-gold-nanoparticles02281nas a2200181   4500008004100000022001400041245018100055210006900236260000800305300001600313490000700329520153800336100002301874700001801897700002601915700003101941856012701972       2023                        eng d  a0743-746300aInfluence of van der waals interactions between the alkyl chains of surface ligands on the size and size distribution of nanocrystals prepared by the digestive ripening process0 aInfluence of van der waals interactions between the alkyl chains  cNOV  a17733-177440 v393 a<p>
	Thermal heating of polydispersed nanocrystals (NCs) with surface-active organic ligands in a solvent leads to the formation of monodispersed NCs, and this process is known as digestive ripening (DR). Here, by performing DR on Au NCs using different-chain-length amine and thiol ligands, we evidently show that ligands with C-12 chain length result in the formation of NCs with narrow size distributions when compared to C-8, C-16, and C-20 chain length ligands. Furthermore, our findings also show that in the case of alkyl thiol, the NC size remains more or less the same, while the size distribution gets altered significantly with the chain length. On the other hand, both size and size distribution are affected significantly when the alkyl amine chain length is varied. Fourier transform infrared (FTIR) studies indicate that the van der Waals (vdW) interactions are weakest when the amine with C-12 carbon chain is used as the DR agent, while in the case of thiols, molecules with C-8 and C-12 chain lengths have nearly the same vdW interactions (with C-12 slightly weaker than C-8), which are weaker than those of C-16 and C-20. Molecular dynamics (MD) simulation results corroborate the experimental observations and suggest that due to more defects in the alkyl chain, the C-8 and C-12 (amine as well as thiol) ligands are disordered and less stable on Au(111) and Au(100) surfaces. This could result in efficient etching and redeposition, making the ligands with C-8 and C-12 chain lengths the better DR agents.</p>
1 aShimpi, Jayesh, R.1 aThomas, Rinto1 aMeena, Santosh, Kumar1 aPrasad, Bhagavatula, L. V.  uhttps://library.ncl.res.in/content/influence-van-der-waals-interactions-between-alkyl-chains-surface-ligands-size-and-size01995nas a2200169   4500008004100000022001400041245013600055210006900191260000800260300001600268490000700284520133200291100002001623700002701643700002601670856012901696       2025                        eng d  a2470-134300aInvestigating the design of ssPalmO-derived lipid nanoparticles for mRNA delivery applications using molecular dynamics simulations0 aInvestigating the design of ssPalmOderived lipid nanoparticles f  cDEC  a61256-612670 v103 a<p>
	The rational design of lipid nanoparticles (LNPs) is essential for the effective transport of drugs and genetic material, as their structural and dynamic properties are heavily influenced by lipid composition and functional group modifications. In this study, we employed molecular dynamics simulations with density functional theory (DFT) derived force fields to investigate the bilayer properties of ssPalmO lipids, their phenyl ester (ssPalmO-phe) and benzyl ester (ssPalmO-ben) derivatives, as well as their cis and trans isomers. While all systems formed stable bilayers, cis-ssPalmO deviated by adopting a flexible, nonlamellar architecture. Trans isomers of ssPalmO-phe and ssPalmO-ben exhibited greater bilayer thickness, packing density, and order parameters due to stronger intramolecular chain interactions, while their aromatic substituents reduced lateral diffusion relative to ssPalmO. Trans isomers exhibited lower electrostatic potential differences, which increased upon incorporation of helper lipids, concomitantly enhancing bilayer packing and thickness while suppressing diffusion. These results clarify how lipid functionalization, stereochemistry, and helper lipid composition modulate bilayer organization, offering molecular level guidance for rational LNP design in drug and mRNA delivery.</p>
1 aBarange, Anjana1 aLuwang, Meitram, Niraj1 aMeena, Santosh, Kumar  uhttps://library.ncl.res.in/content/investigating-design-sspalmo-derived-lipid-nanoparticles-mrna-delivery-applications-using