Surfactant system-based nanoparticle

The properties of a microemulsion will to a great extent depend on the nature of the surfactant. Surfactants may be non-ionic, anionic or cationic. Previous studies have shown that a suitable system for the preparation of metallic nanoparticles consists of a non-ionic surfactant such as pentaethyleneglycol-dodecylether, hexane and water (Figure 2). A water-soluble precursor can be added to the system and thus, a reasonable amount of nanosized metal particles may be obtained. In some particular cases, systems based on ionic surfactants such as AOT or cationic surfactants such as cetyltriammonium bromide (CTAB) will give a lower solubility of the metal precursor. ... 

However, an alternative to using surfactant systems is to use nanopartide-based PSPs directly. They are more compatible with mass spectrometric (MS) detection and do not hamper electrospray ionization (ESI) [49]. In that respect, nanopartides from silica [50], gold [51] and polymers [52] and even molecularly imprinted nanoparticles [53] have been used. Imprinting is based on a technique for tailor-making network polymers, where templates for a specific solute give a high separation affinity. 

PUs are often used as nanomaterial carriers, but PU-based nanoparticles have also been reported. Most of the nanoparticles have been synthesized by miniemulsion techniques [76]. Miniemulsions are stable aqueous dispersions of oil droplets, which are prepared by high shear of a system containing oil, water, surfactant, and a hydrophobe. 

One of synthetic approaches for the iron nanoparticles is based on the widely used decomposition of iron pentacarbonyl [19, 361, 362], The novelty of the approach is the surfactant system used. Studies with a number of strongly bound surfactants have resulted in decreased magnetic response, due to surface oxidation, disturbing the electronic structure of the surface atoms, or some other mechanism. With this in mind, ones chose to work with a weak surfactant, a p-diketone. P-diketones do have a history as adhesion promoters in bonds between metals and polymers [363], The limited reactivity of p-diketones is as an advantage the P-diketone is much weaker oxidizer than carboxylic acids or alcohols and will not oxidize iron, it is not as nucleophilic as phosphines, yet it is known to be capable of chelating iron. 

As shown in the Figure le, incorporation of 1 wt % of Ti02 change completely morphology generated in the thermosetting based system. UV treatment allowed to visualised well-dispersed titanium dioxide nanoparticles. Thus, confirm that LC act in this quaternary system as surfactant for TiOa nanoparticles. Additionally, LC as partially miscible with the PS-block of PSEO allowed to control dispersion of the Ti02 nanoparticles in the microphase separated PS-block-rich phase. 

Xylans from beech wood, corncobs, and the alkaline steeping liquor of the viscose process have been shown to be applicable as pharmaceutical auxiliaries [3]. Micro- and nanoparticles were prepared by a coacervation method from xylan isolated from corncobs [150]. The process is based on neutralization of an alkaline solution in the presence of surfactant, which was shown to influence both the particle size and morphology. They are aimed at applications in drug delivery systems. 

Solubility enhancement systems lipid-based systems, nanoparticles, surfactants, semisolid formulations... 

Dye-Doped Silica Nanoparticle Synthesis Using Nonionic Surfactant-Based Microemulsion Systems... 

Silica Nanoparticles. The base-catalyzed hydrolysis of silicon aikoxides in microemulsions produces nanoparticles (20-39). Aqueous ammonia has been used primarily as the base, with AOT and nonionic polyoxyethylene ethers as the main surfactants. Figure 2.2.6 presents a flow diagram for the synthesis of pure silica (23-32) the microemulsion is first prepared and then the alkoxide is added. As can be seen from Table 2.2.1, the microemulsions include the systems AOT/ isooctane/water/ammonia, AOT/toluene/water/ammonia, NP-5/cyclohexane/water/ ammonia, and NP-4/heptane/water/ammonia. Typical reaction times are l -5 days. Various modified silica nanoparticles have also been prepared, including hydropho-... 

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