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S. A. Pauline
phosphate ceramics and the CDHA with desired Ca/P ratio can be synthesized
by mechanochemical synthesis method by varying the reaction conditions. Nano
size crystals of hydroxyapatite of size around 20 nm and controlled Ca/P ratio was
reported to be produced by this method [33].
2.5 Microemulsion Method
Micelles are formed by self-assembly of surfactants or block copolymers when they
are present above a critical concentration in air or aqueous solution. The synthesis
of nanoceramics takes place inside the confined space in the micelle or microemulsion. A microemulsion is produced by dispersing an organic solution in an aqueous
solution in the form of fine liquid droplets. The reactants are dissolved and are
present in the organic droplets. The reaction happens at the interface between the
organic and aqueous part [19]. The reaction will continue and nanoceramic will be
produced till reactants are available inside the micelle. This method enables control of
particle size, morphology, shape and surface area of the nanoceramic. Mesoporous
HAp was prepared by microemulsion technique using hecadecyltrimethyl ammonium bromide (CTAB), cyclohexane and n-octyl alcohol. The HAp powders had
well-ordered and uniform morphology with broader pore size distribution. The HAp
powders had good biocompatibility at low concentrations and low toxicity at high
concentrations and hence are suitable for bone tissue grafts, drug delivery and also
for coating material [34]. Iron oxide nanoparticles are produced using the copolymer,
poly(styrene-block-allyl alcohol) by microemulsion method. Hydrophobic nanoparticles are encapsulated into the iron oxide nanoparticles to obtain multi-functional
nanocomposite. Fluorescent dye and anti-cancer drug molecules are loaded into them
and it was observed that the nanocomposite enabled imaging-guided and magnetic
targeted drug delivery [35].
2.6 Wet Chemical Deposition
Wet chemical deposition method represents chemical reactions occurring in the solution phase using appropriate precursors and experimental conditions. Many wet
chemical synthesis methods are known such as solvothermal synthesis, template
synthesis, self-assembly, hot-injection, metal-organic decomposition, etc., by which
nanomaterials can be effectively produced [36]. HAp nanostructures were synthesized by wet chemical synthesis method at different pH values and sintering temperatures. The rod and flake-like HAp structures that have formed have an enhanced
Ca/P ratio of 1.83 and an increased crystallite size from 20 to 56 nm. Stable and
porous Hap powders were synthesized by this method [37]. Needle-like and platelike Mg-substituted Hap particles containing different amounts of Mg were prepared
S. A. Pauline
phosphate ceramics and the CDHA with desired Ca/P ratio can be synthesized
by mechanochemical synthesis method by varying the reaction conditions. Nano
size crystals of hydroxyapatite of size around 20 nm and controlled Ca/P ratio was
reported to be produced by this method [33].
2.5 Microemulsion Method
Micelles are formed by self-assembly of surfactants or block copolymers when they
are present above a critical concentration in air or aqueous solution. The synthesis
of nanoceramics takes place inside the confined space in the micelle or microemulsion. A microemulsion is produced by dispersing an organic solution in an aqueous
solution in the form of fine liquid droplets. The reactants are dissolved and are
present in the organic droplets. The reaction happens at the interface between the
organic and aqueous part [19]. The reaction will continue and nanoceramic will be
produced till reactants are available inside the micelle. This method enables control of
particle size, morphology, shape and surface area of the nanoceramic. Mesoporous
HAp was prepared by microemulsion technique using hecadecyltrimethyl ammonium bromide (CTAB), cyclohexane and n-octyl alcohol. The HAp powders had
well-ordered and uniform morphology with broader pore size distribution. The HAp
powders had good biocompatibility at low concentrations and low toxicity at high
concentrations and hence are suitable for bone tissue grafts, drug delivery and also
for coating material [34]. Iron oxide nanoparticles are produced using the copolymer,
poly(styrene-block-allyl alcohol) by microemulsion method. Hydrophobic nanoparticles are encapsulated into the iron oxide nanoparticles to obtain multi-functional
nanocomposite. Fluorescent dye and anti-cancer drug molecules are loaded into them
and it was observed that the nanocomposite enabled imaging-guided and magnetic
targeted drug delivery [35].
2.6 Wet Chemical Deposition
Wet chemical deposition method represents chemical reactions occurring in the solution phase using appropriate precursors and experimental conditions. Many wet
chemical synthesis methods are known such as solvothermal synthesis, template
synthesis, self-assembly, hot-injection, metal-organic decomposition, etc., by which
nanomaterials can be effectively produced [36]. HAp nanostructures were synthesized by wet chemical synthesis method at different pH values and sintering temperatures. The rod and flake-like HAp structures that have formed have an enhanced
Ca/P ratio of 1.83 and an increased crystallite size from 20 to 56 nm. Stable and
porous Hap powders were synthesized by this method [37]. Needle-like and platelike Mg-substituted Hap particles containing different amounts of Mg were prepared