A Novel Approach to Controlling CaCO₃Crystalline Assembly by Changing the Concentration of Poly(aspartic acid)

Abstract

CaCO 3 crystalline structures having novel assemblies were in situ fabricated as analogs of naturally occurring proteins and polysaccharides for biomineralization. The calcite crystal was mineralized in a poly(vinyl alcohol)-Ca 2+ complex film immersed in a Na 2 CO 3 solution containing poly(aspartic acid). The morphology and size of the CaCO 3 crystals were tuned by varying the concentration of poly(aspartic acid). The mechanisms of their nucleation orientation and formation were investigated experimentally and through molecular dynamics (MD) simulations in order to obtain a better understanding of the interactions between the polymers and the crystal at the molecular level. Both the MD results and experimental results indicate that the interaction between PVA and calcite mainly depends on the concentration of the polymer. The novel approach proposed herein for the fabrication of inorganic crystalline assembly structures can be used to fabricate precise crystalline structures.

Plasmon-Induced Photoluminescence Immunoassay for Tuberculosis Monitoring Using Gold-Nanoparticle-Decorated Graphene

“…Note that a high binding energy indicates a high adhesive or repulsive strength between the Au NPs and the graphene layer, and the ± signals in front of the numbers indicate the nature of the force, i.e., whether it is attractive (+) or repulsive (−). 23 The binding energies were calculated using the condensed-phase optimized molecular potentials for atomistic simulation studies (COMPASS) force field, and the results are listed in Table 1. From the results of the computational simulation, the graphene/graphene binding energy without an inserted Au NP layer (denoted "BL") was slightly negative; this may be a computational artifact due to the fact that the model maintained a fixed distance between the two layers, which requires a repulsive force.…”

“…Table gives the binding energies between the Au NPs and each graphene layer, which were calculated using where E graphene is the energy of the graphene layer, E AuNPs is the energy of the Au NPs, and E total is the energy of the graphene layer with Au NPs. Note that a high binding energy indicates a high adhesive or repulsive strength between the Au NPs and the graphene layer, and the ± signals in front of the numbers indicate the nature of the force, i.e., whether it is attractive (+) or repulsive (−) . The binding energies were calculated using the condensed-phase optimized molecular potentials for atomistic simulation studies (COMPASS) force field, and the results are listed in Table .…”