The chemistry of nanomaterial and nanobiomaterial

Nanomaterials and nanobiomaterials are materials which are currently subject to intense research while at the same time their usage in development of various technological applications is also moving at a very swift pace. Advances in this area of research are consequent to the realization that nanomaterials and nanobiomaterials have profound influence on improvement of various aspects of life quality as well as other industrial aspects. Layered two dimensional inorganic materials, especially layered double hydroxides (LDH) have versatile properties due to its intercalation and deintercalation characters. By hybridization of LDH with beneficial functional active agents, various new host-guest nanohybrids with tailor made properties can be generated. If the guest is a biomaterial such as DNA or plasmid, then the nanohybrid can be used as vector for plasmid transfaction. On the other hand, if a drug is encapsulated into the LDH interlamellae, then the nanohybrid can be used as a controlled release formulation. On the other hand, if active agents such as herbicides, plant growth regulators, etc. are used, then a new generation of agrochemicals which is safer, user- and environmentally-friendly can be generated. LDH composed of nickel calcined at high temperature of around 800 oC is suitable to be used as the catalyst precursor for carbon nanotubes preparation. This is due to the better dispersion of the nickel nanoparticles used for the formation of multiwalled carbon nanotubes. This work provides understanding of some important fundamental considerations necessary for the design and formation of new functional materials especially nanomaterials and nanobiomaterials of nanohybrid type. The materials can be used to store beneficial agents in the nanolayered interlamellae, transport it to the target and subsequent controlled release. In addition, using biomaterial such as bacteria as biotemplating agents coupled with the hydrothermal method to generate new nanostructured materials open up new methods of synthesis by the green chemistry route. These offer avenues for a new class of nanomaterials with physical and chemical properties that can be tailor made

Gallate-Zn-Al-layered double hydroxide as an intercalated compound with new controlled release formulation of anticarcinogenic agent.

A new organic-clay material, in which the organic moiety is intercalated into the inorganic interlayer, was prepared using gallate anion (GA) as a guest, and Zn–Al-layered double hydroxide, as clay host. The ion-exchange technique was found to be effective for the intercalation process in the formation of the compound. Although the basal spacings of the LDH and its intercalated product were fairly similar, FTIR, CHNS and TGA/DTG results indicated that the GA was actually intercalated into the interlayer of the host in parallel orientation. The resulting nanostructure material possessed a well ordered layered structure with 42.2% GA loading (w/w). The release of the anion from the interlayer of the intercalated compound was found to be of controlled manner, governed by the first order kinetic and it was also concentration dependent. The material has potential as a nano-storage of anticarcenogenic agent with controlled delivery capability

Controlled release study of an anti-carcinogenic agent, gallate from the surface of magnetite nanoparticles.

Immobilization of gallate anion, an anti-carcinogenic, anti-mutagenic, and anti-microbial agent on the surface of magnetite nanoparticles was accomplished by adsorption technique for the formation of a core–shell nanocomposite. A simple co-precipitation technique in the presence of poly vinyl pyrrolidone was successfully applied for the preparation of magnetite nanoparticles as core beads with narrow size distribution. The powders were characterized by X-ray diffraction, particle size analysis, magnetic measurements, atomic force microscope and also infrared spectroscopy. FTIR and CHNS results indicated that the gallate anion was actually adsorbed onto the surface of the magnetite nanoparticles. The release of the anion from the surface of the nanocomposite was found to be controllable by the selection of the release media

Synthesis of Glutamate-Zinc-Aluminium-Layered Double Hydroxide Nanobiocomposites and Cell Viability Study

A layered compound of zinc-aluminium layered double hydroxide (LDH) to be used as a host for a guest amino acid, glutamate was synthesized. Different parameters were used and optimized to form amino acid-intercalated pure phase materials. The resulting Bio-Inorganic Nanohybrid (BINH) was chosen for further characterization. BINH exhibits the glutamate to be in vertical or perpendicular orientation to the inorganic layer. Cytotoxicty test indicates that the IC50 value was observed at 3.125 μg/ml. Results from this study will be used in the development of a new delivery system for therapeutic agents comprising amino acids or peptides

Cathodic electrodeposition of SnS thin films from aqueous solution

SnS thin films were prepared by cathodic electrodeposition on ITO/glass and Ti substrates from a solution containing SnCl2 and thiosulphate ions. Cyclic voltammetry experiments were performed to elucidate the electrodic processes occurred when potentials were applied and to determine the optimum potential for electrodeposition. The photoactivity of the deposited films and their conduction types were evaluated using the photoelectrochemical technique. The bandgap energy and type of optical transitions were determined from optical absorbance data. Structural and compositional analysis were accomplished using X-ray diffractometry, electron dispersive analysis of X-ray, and X-ray photoelectron spectroscopy. The morphology of the films were examined using scanning electron microscopy

Kitar voltametri pengelektroenapan timah dan timah sulfida di atas titanium dalam larutan akueous

Cyclic voltammetry showed that Sn can be deposited on Ti electrode from aqueous solution containing SnCl2 at overpotential of at least 0.06 V. SnS can also be electrodeposited from the mixture of aqueous solution of SnCl2 and thiosulphate at potential greater than -0.5V vs SCE. The existence of small stripping peak marked Sn element content in the deposit. The stoichiometry of the deposit may be approached by controlling the deposition potential and solution composition

Controlled Release Compound Based on Metanilate-Layered Double Hydroxide Nanohybrid

Metanilate-layered double hydroxide nanohybrid compound was synthesized for controlled release purposes through co-precipitation method of the metal cations and organic anion. The effect of various divalent metal cations (M2+), namely Zn2+, Mg2+ and Ca2+ on the formation of metanilate-LDH nanohybrids, in which metanilate anion was intercalated into three different layered double hydroxide (LDH) systems; Zn-Al, Mg-Al and Ca-Al were investigated. The syntheses were carried out with M2+ to Al3+ initial molar ratio, R of 4. The pH of the mother liquor was maintained at pH 7.5 and 10 during the synthesis, and the resulting mixture was aged at around 70 °C for about 18 h. The intercalation of metanilate anion into the host was found to be strongly influenced by the M2+ that formed the inorganic metal hydroxide layers. Under our experimental condition, the formation of the nanohybrid materials was found to be more feasible for the Zn-Al than for the other two systems, in which the former showed well-ordered layered organic-inorganic nanohybrid structure with good crystallinity. Intercalation is confirmed by the expansion of the interlayer spacing to about 15-17 Å when metanilate was introduced into the interlamellae of Zn-Al LDHs. In addition, CHNS and FTIR analyses also support that metanilate anion has been successfully intercalated into the interlamellae of the inorganic LDH. Apart from M2+, this study also shows that the initial pH of the mother liquor plays an important role in determining the physicochemical properties of the resulting nanohybrids, especially the mole fraction of the Zn2+ substituted by the Al3+ ion in the LDH inorganic sheets which in turn controlled the loading percentage of the organic anion, surface properties and the true density. Preliminary study shows that LDH can be used to host beneficial guests, active agent with controlled release capability of the guests. Generally the overall process is governed by pseudo second order kinetic but for the first 180 min, the release process can be slightly better described by parabolic diffusion than the other models

Preparation of RF/Brij 58 mesoporous carbon film as supercapacitor electrode

Mesoporous carbon (MC) film was prepared using carbon precursor of resorcinol and formaldehyde via self-assembly soft templating method for supercapacitor application with high electrochemical performance. A neutral surfactant of Brij 58 was used as structure directing agent for the pore structure geometry tuning while preparing the MCs. It was then carbonized to obtain the ordered mesoporous carbon (OMC) films or namely as RF/Brij58 film. The mesostructure was characterized by X-ray diffraction patterns (XRD) and electrochemical analysis. The carbonized RF/Brij58 film show excellent electrochemical property for supercapacitor application and the specific capacitance up to 10.57 mFcm-1 at 5 mV s−1 scan rate was obtained

Adsorption of methylene blue onto treated activated carbon

The potential feasibility of treated and untreated activated carbon for removal of methylene blue from aqueous solution was investigated. The effects of various experimental parameters such as contact time, solution pH and adsorbent dosage were investigated. The extent of methylene blue removal increased with the increased in contact time, solution pH and amount of adsorbent used. Adsorption data was better fitted to the Langmuir isotherm. The results in this study indicated that the treated activated carbon was an attractive candidate for removing organic dye of methylene blue which shows great reduction of colour while reducing the time contact to achieve equilibrium