The present invention provides an in vitro system for compartmentalization of mol. or cellular libraries and provides methods for selection and isolation of desired mols. or cells from the libraries. The library includes a plurality of distinct mols. or cells encapsulated within a water-in-oil-in-water emulsion. The emulsion includes a continuous external aq. phase and a discontinuous dispersion of water-in-oil droplets. The internal aq. phase of a plurality of such droplets comprises a specific mol. or cell that is within the plurality of distinct mols. or cells of the library. Thus, for example, mutants with improved β-galactosidase activity can be selected from a random mutagenesis library of evolved β-galactosidase lacZ gene using a double emulsion selection system. [on SciFinder(R)]

The invention relates to an ink-jet ink compn. for printing on a ceramic substrate comprising: (a) a liq. vehicle; (b) sub-micron particles of binding compn. having a m.p. below 6000C; and (c) sub-micron particles causing an etch-like effect, said sub-micron particles are selected from metal oxide particles, high m.p. frit particles, and a combination thereof, said sub-micron particles causing an etch-like effect have a m.p. of at least 500C above the m.p. of said sub-micron particles of binding compn. The invention further relates to a printing process using such ink and to a ceramic substrate printed with a pattern or image having an etch-like effect, by means of the printing process. [on SciFinder(R)]

A review. Current approaches to the prepn. of nanoparticles in confined structures are described. The prepn. of inorg. and org. nanoparticles in nanometric confined structures, such as reverse micelles, water-in-oil and oil-in-water microemulsions, water-in-supercrit. liq. microemulsions, micelles of amphiphilic block copolymers, miniemulsions, dendrimers, polymeric capsules, pore channels of mesoporous solids, and nanoporous membranes, and liq. crystals are discussed. Examples of practical applications of the nanoparticles obtained are presented. [on SciFinder(R)]

We describe a new method for the prepn. of org. nanoparticles from nanoemulsions which were prepd. by the phase inversion temp. (PIT) method. This is a low-energy technique which does not require any special equipment such as high pressure homogenizers. In this work, the method is demonstrated for prepn. of nanoparticles of poly-lauryl acrylate contg., in some cases, a crosslinker (trimethylolpropane triacrylate-TMPTA) and pyrene as microviscosity and micropolarity probes, resp. The nanoemulsions were prepd. by using a poly(oxyethylene) nonionic surfactant, Brij 96V (POE (10) oleyl alc.), and combinations of Brij 96V and Brij 92V (POE (2) oleyl alc.), with acrylate monomers which form the oil phase in the oil-in-water (O/W) emulsions. The nanodroplets were polymd., yielding nanoparticles having an av. diam. between 50 and 120 nm with a narrow size distribution, using a water-sol. thermal initiator (ammonium persulfate) and activated by ferrous ions, Fe+2. The emission colors of the pyrene-embedded nanoemulsions changed from blue to violet after polymn., due to the absence of excimers. This method may be applied for the prepn. of a variety of polymeric nanoparticles, in which functional mols. are embedded within the particles. [on SciFinder(R)]

A new method for the prepn. of nanoparticles from nano-emulsions using a low-energy emulsification method based on phase inversion at const. temp. (catastrophic inversion) is described. This method does not require any special equipment such as high-pressure homogenizers. The method is demonstrated for the prepn. of Et cellulose nanoparticles contg. pyrene (a microviscosity and micropolarity probe) as a hydrophobic model mol. The nano-emulsions were prepd. using a combination of non-ionic surfactants: Polyglycerol fatty acid ester (decaglycerol mono laurate) and sorbitan ester (Span 20), volatile org. solvent (toluene) and Et cellulose. Toluene was evapd. from the nano-emulsions, resulting in Et cellulose nanoparticles 50-120 nm in size. The emission colors of the pyrene-embedded nano-emulsions changed from blue to violet after the evapn. of the toluene because of the absence of excimers. This method may be applied for the prepn. of a variety of polymeric nanoparticles in which functional mols. are embedded within the particles. [on SciFinder(R)]

The efficient amplification of genomic libraries, cDNA libraries and other complex mixts. of genes by PCR is impeded by two phenomena: firstly, short fragments tend to be amplified in preference to larger ones; and, secondly, artifactual fragments are generated by recombination between homologous regions of DNA. Recombination in this case occurs when a primer is partially extended on one template during one cycle of PCR and further extended on another template during a later cycle. Thus, chimeric mols. are generated, the short ones of which are then preferentially amplified. A variety of PCR protocols have been proposed to minimize these problems, most of which rely on high template concns. and low nos. of PCR cycles. Clearly, however, such an approach is not viable if little template DNA is available. Here we describe a protocol for amplifying complex DNA mixts., based on the compartmentalization of genes in a water-in-oil (w/o) emulsion. Template fragments are segregated in the minute aq. droplets of the emulsion and amplified by PCR in isolation. This approach alleviates the problems described above while enabling the use of small amts. of template DNA and high nos. of PCR cycles. Box 1 described an alternative method for generating very stable emulsions for emulsion PCR using the surfactant ABIL EM 90. [on SciFinder(R)]

The invention relates to a method for prepg. an aq.-based dispersion of metal nanoparticles comprising: (a) pre-reducing a metal salt suspension by a H2O sol. polymer capable of metal redn. to form a metal nuclei; and (b) adding a chem. reducer to form metal nanoparticles in dispersion. The invention further relates to aq.-based dispersions of metal nanoparticles, and to compns. such as inks comprising such dispersions. [on SciFinder(R)]

Organoleptically acceptable chewing gums (composed of a gum base, at least one edible acid, and optionally other ingredients) are characterized by high adherence to plaque bacteria. Thus, a ratio between gum base and malic acid of 60:1.8 may be used. A method for prepg. the chewing gum includes triturating a coloring agent (e.g., carmoisine). A method for com. producing and marketing the chewing gums includes testing the chewing gums for adhesion to bacteria, such as plaque bacteria. [on SciFinder(R)]

The goal of in vitro compartmentalization (IVC) is to divide a large reaction between many microscopic compartments. This technique was first developed to generate "artificial cells" for the directed evolution of proteins. Typically, an aq. soln. of genes and an in vitro transcription-translation system is stirred (or homogenized) into an oil-surfactant mixt. to create a water-in-oil (w/o) emulsion with -1010 aq. droplets per mol of emulsion. The majority of droplets contain no more that a single gene along with all of the mol. machinery needed to express that gene. The expressed proteins and the products of their catalytic activities cannot leave the droplets, and so genotype is coupled to phenotype in vitro, making it possible to select very large libraries of genes (108-1011 genes). We describe the advantages and applications of IVC. A protocol for performing a directed evolution expt. by IVC makes use of one or more w/o emulsions. This procedure involves the generation of a gene library, the performance of a selection, and the subsequent recovery of the selected genes by PCR. We also describe two procedures for converting w/o emulsions to water-in-oil-in-water (w/o/w) emulsions for high-throughput screening using a fluorescence-activated cell sorter (FACS). Finally, we describe two methods for delivering substrates, regulators and other compds. to the preformed aq. droplets of w/o emulsion. [on SciFinder(R)]

The present invention provides an in vitro system for compartmentalization of large mol. libraries and provides methods for selection and isolation of mols. having desired activities from such libraries. The present invention provides novel and inventive applications of IVC for the selection of mols. being capable of modulating a particular activity of a known biol. active moiety, including, but not limited to an enzyme. The inventors of the present invention utilize a micelle delivery system that enables the transport of various solutes, including metal ions, into the emulsion droplets thereby inducing a desired activity of the known biol. active moiety or of the gene product. The present invention is based ion part on the unexpected finding that an IVC system can be used for directed evolution of nuclease inhibitors. In vitro compartmentalization (IVC) uses water-in-oil emulsions to create artificial cell-like compartments in which genes can be individually transcribed and translated. Here, the inventors present a new application of IVC for the selection of DNA-nuclease inhibitors. They developed a nano-droplets delivery system that allows the transport of various solutes, including metal ions, into the emulsion droplets. This transport mechanism was used to regulate the activity of colicin nucleases that were co-compartmentalized with the genes, so that the nucleases were activated by nickel or cobalt ions only after the potential inhibitor genes have been translated. They demonstrated its utility by selecting libraries of the gene encoding the cognate inhibitor of colicin E9 (immunity protein 9, or Im9) for inhibition of another colicin (ColE7). The in vitro evolved inhibitors show significant inhibition of ColE7 both in vitro and in vivo. These Im9 variants carry mutations into residues that det. the selectivity of the natural counterpart (Im7) while completely retaining the residues that are conserved throughout the family of immunity protein inhibitors. [on SciFinder(R)]

Pure magnetite nanoparticles (Fe3O4) have been synthesized in water by copptn. using two different approaches (from ferrous sulfate and a mixt. of ferrous and ferric chlorides). All materials aggregated in aq. suspension, but their subsequent dispersion on treatment with a variety of agents was obsd. to be different. Magnetite produced using ferrous sulfate could not be disaggregated, whereas magnetite produced from a mixt. of ferrous and ferric chlorides could be disaggregated to a quasi-monodispersed form. The dispersing agents were tetra-Me ammonium hydroxide, Disperbyk 190 and polyacrylic acid. The finding has potentially important implications for the surface activation of superparamagnetic magnetite nanoparticles and their ability to be used in bio/life science applications. [on SciFinder(R)]

Ink jet printable compns. that include nano metal powders in a liq. carrier are described for printing elec. conductor patterns. These compns. have high metal nanopowder concns. and low viscosities. [on SciFinder(R)]

Nanoparticles of metals having high elec. cond. offer new scope for direct digital printing of conductive patterns. Stable aq. silver nanoparticle dispersions were synthesized by chem. redn. These were suitable for inkjet printing, with the dried inks sintering at temps. as low as 160°. However, the resistance remained much higher than that of metallic silver. [on SciFinder(R)]

A nanoemulsion useful for improving light-fastness of water-based inks comprises nanodroplets of UV stabilizer in water, wherein the nanodroplets comprise (a) water-immiscible liq. phase, which is a UV stabilizer or a mixt. of UV stabilizers, (b) submicron solid particles of at least one UV stabilizer dispersed within said nanodroplets, and wherein the av. size of the droplets is < 350 nm. The nanoemulsion may further comprise one or more light fastness agents selected from UV absorbers, UV blockers, antioxidants, singlet oxygen quenchers, super oxide anion quenchers, ozone quenchers, visible light absorbers, or IR absorbers. [on SciFinder(R)]

The present invention relates to biocompatible polymeric beads and to biocompatible delivery systems comprising same for controlled or sustained release of bioactive mols. In particular, the invention relates to polymeric beads having a two-phase core and shell structure and to polymeric delivery systems comprising same that provide sustained release of the bioactive compd. A method of prepg. the biocompatible polymeric beads, comprises: (1) mixing an aq. soln. or suspension of the bioactive compd. in an oily phase to form a water-in-oil emulsion, in the presence of at least one surface active agent; (2) homogenizing the mixt.; (3) applying a polymeric shell around small droplets of the emulsion by means of core/shell extrusion; and (4) solidifying the shell to form two phase core-and-shell-structured polymeric beads. For example, both emulsion and suspension bead expts. were conducted with micronized halofuginone·HBr (I). A water-in-oil emulsion was prepd., in which the internal phase contained I and the oil was sunflower oil. Beads were formed by a core-shell double nozzle using a shell soln. contg. Na alginate and a crosslinking agent contg. CaCl2. [on SciFinder(R)]

The present invention relates to biocompatible polymeric delivery systems for controlled or sustained release of quinazolinone derivs.(I; n = 1-2; R1 = H, halo, NO2, benzo, alkyl, Ph, alkoxy; R2 = OH, acetoxy, alkoxy; R3 = H, alkenoxy carbonyl), including the compd. halofuginone. In particular the invention relates to a polymeric delivery system comprising biocompatible polymeric beads having a two-phase core and shell structure, or polymeric films, beads or complexes that provide local sustained release of the pharmacol. agent. For example, polymeric emulsion beads with core/shell structure were prepd. for controlled release of halofuginone. A water-in-oil emulsion was prepd., in which the 20% wt. internal phase contained 50 mg halofuginone HBr/mL and the oil was sunflower oil. The emulsion was prepd. by adding the aq. halofuginone soln. in to the oil which contains 2.7% wt. span 80, and homogenized. Beads were formed by a core-shell double nozzle Innotek. The shell soln. was 2.5% sodium alginate and 2.5% silica in aq. soln. [on SciFinder(R)]

In vitro compartmentalization (IVC) uses water-in-oil emulsions to create artificial cell-like compartments in which genes can be individually transcribed and translated. Here, we present a new application of IVC for the selection of DNA-nuclease inhibitors. We developed a nano-droplets delivery system that allows the transport of various solutes, including metal ions, into the emulsion droplets. This transport mechanism was used to regulate the activity of colicin nucleases that were co-compartmentalized with the genes, so that the nucleases were activated by nickel or cobalt ions only after the potential inhibitor genes have been translated. Thus, genes encoding nuclease inhibitors survived the digestion and were subsequently amplified and isolated. Selection is therefore directly for inhibition, and not for binding of the nuclease. The stringency of selection can be easily modulated to give high enrichments (100-500-fold) and recoveries. We demonstrated its utility by selecting libraries of the gene encoding the cognate inhibitor of colicin E9 (immunity protein 9, or Im9) for inhibition of another colicin (ColE7). The in vitro evolved inhibitors show significant inhibition of ColE7 both in vitro and in vivo. These Im9 variants carry mutations into residues that det. the selectivity of the natural counterpart (Im7) while completely retaining the residues that are conserved throughout the family of immunity protein inhibitors. The in vitro evolution process confirms earlier hypotheses regarding the "dual recognition" binding mechanism and the way in which new colicin-immunity pairs diverged from existing ones. [on SciFinder(R)]

{The present invention provides a drug delivery system comprising nanoparticles or microparticles of a water poorly sol. drug dispersed in a polymeric bead contg. essentially only of hydrophilic polymers (i.e., without hydrophobic polymers). The present invention further provides a method of producing the drug delivery system of the invention. Thus, a 4% sodium alginate soln. was prepd. by mixing 16 g of sodium alginate and 400 g water together with 0.4 g of Bronopol (preservative) at about 37° until complete dissoln. A crosslinking agent was prepd. by dissolving 14.8 g of calcium chloride dihydrate in 1000 g water. An oil-in-water emulsion (20% oil phase, 80% aq. phase) was prepd. contg. 3% surfactant (mixt. of Tween 20 and Span 20