Effect of dietary supplementation of Bacillus subtilis TLRI 211-1 on laying performance, egg quality and blood characteristics of Leghorn layers.

Objective: TLRI 211-1 is a novel Bacillus subtilis strain. This experiment was to investigate dietary supplementation of TLRI 211-1 on laying performance, egg quality and blood characteristics of layers.

Methods: One hundred and twenty 65-wk-old Leghorn layers were divided into four treatment groups for 8 weeks experiment.

Quantification of saccharides in honey samples through surface-assisted laser desorption/ionization mass spectrometry using HgTe nanostructures.

Quantification of monosaccharides and disaccharides in five honey samples through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using HgTe nanostructures as the matrix and sucralose as an internal standard has been demonstrated. Under optimal conditions (1× HgTe nanostructure, 0.2 mM ammonium citrate at pH 9.

Gold nanosponges: green synthesis, characterization, and cytotoxicity.

A simply approach for the synthesis of Au nanostructures in tea infusions at room temperature is developed. By controlling the concentrations of tea infusions, Au nanostructures in various shapes and sizes have been prepared. From 1 x (original concentration) and 0.

Using surface-assisted laser desorption/ionization mass spectrometry to detect ss- and ds-oligodeoxynucleotides.

We applied surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) with HgTe nanostructures as the matrix for the detection of single- and double-stranded oligodeoxynucleotides (ss-ODNs and ds-ODNs). The concentrations of surfactant and additives (metal ions, an amine) and the pH and ionic strength of the sample matrix played significantly different roles in the detection of ss- and ds-ODNs with various sequences. In the presence of Brij 76 (1.

Analysis of the formation process of gold nanoparticles by surface-assisted laser desorption/ionization mass spectrometry.

Chemical reactions of reducing agents in the gold nanoparticle (AuNP) formation process were characterized using surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). As the reaction of the AuNPs progresses, the produced AuNPs can serve as an efficient SALDI substrate. SALDI-MS revealed that the reducing agents and their oxidation products can be determined in the mass spectra.

Enzyme mimics of Au/Ag nanoparticles for fluorescent detection of acetylcholine.

We have developed a highly sensitive and selective fluorescent assay for the detection of acetylcholine (ACh) based on enzyme mimics of Au/Ag nanoparticles (NPs). These NPs were prepared via a one-step solution phase reaction between 13 nm Au NPs and Ag(+) ions in the presence of stabilizing agents such as adenosine triphosphate (ATP) and polyethylene glycol (PEG). Our sensing strategy involves reacting ACh with acetylcholinesterase (AChE) to form choline that is in turn oxidized by choline oxidase (ChOx) to produce betaine and H(2)O(2), which reacts with Amplex UltraRed (AUR) in the presence of bimetallic NPs catalyst to form a fluorescent product.

Catalytic gold nanoparticles for fluorescent detection of mercury(II) and lead(II) ions.

In this study, we developed a fluorescence assay for the highly sensitive and selective detection of Hg(2+) and Pb(2+) ions using a gold nanoparticle (Au NP)-based probe. The Hg-Au and Pb-Au alloys that formed on the Au NP surfaces allowed the Au NPs to exhibit peroxidase-mimicking catalytic activity in the H(2)O(2)-mediated oxidation of Amplex UltraRed (AUR). The fluorescence of the AUR oxidation product increased upon increasing the concentration of either Hg(2+) or Pb(2+) ions.

Detection of melamine in infant formula and grain powder by surface-assisted laser desorption/ionization mass spectrometry.

We have developed a method for the determination of melamine (MEL), ammeline (AMN), and ammelide (AMD) by surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using gold nanoparticles (Au NPs). The major peaks for MEL, AMN, and AMD at m/z 127.07, 128.

Using surface-assisted laser desorption/ionization mass spectrometry to detect proteins and protein-protein complexes.

In this study, we combined surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) with HgTe nanostructures as matrix for the detection of several proteins (α1-antitrypsin, trypsin, IgG, protein G) and their complexes. We investigated the effects of several parameters (the concentration and nature of surfactants and metal ions, the pH, and concentration of the analytes in the sample matrixes) on the sensitivity of the detection of these proteins and their complexes. The presence of stabilizing Brij 76 surfactant and Zn(II) ions allowed the detection of weak protein complexes, such as α1-antitrypsin-trypsin and IgG-protein G complexes, at the picomole level.

Nanoparticle-based mass spectrometry for the analysis of biomolecules.

Nanoparticles (NPs) are useful as matrixes for the analyses of several types of biomolecules (including aminothiols, peptides, and proteins) and for mass spectrometric imaging through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS), mainly because of their large surface area, strong absorption in the ultraviolet-near-infrared region, and ready functionalization. Metallic NPs, metal oxide NPs, and semiconductor quantum dots, unmodified or functionalized with recognition ligands, have a strong affinity toward analytes; therefore, they allow the enrichment of biomolecules, leading to improved sensitivity with minimal matrix interference in their mass spectra. SALDI-MS using NPs overcomes the two major problems commonly encountered in matrix-assisted laser desorption/ionization mass spectrometry: the presence of "sweet spots" and the high background signals in the low-mass region.

Detection of proteins and protein-ligand complexes using HgTe nanostructure matrixes in surface-assisted laser desorption/ionization mass spectrometry.

We have analyzed peptides, proteins, and protein-drug complexes through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using HgTe nanostructures as matrixes. We investigated the effects of several parameters, including the concentration of the HgTe nanostructures, the pH of the buffer, and the concentration of salt, on the performance of this system. When HgTe nanostructures are used as matrixes, [M + H](+) ions were the dominant signals.

Exploring the interactions between gold nanoparticles and analytes through surface-assisted laser desorption/ionization mass spectrometry.

Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) is applied to provide strong evidence for the chemical reactions of functionalized gold nanoparticles (Au NPs) with analytes--Hg(2+) ions induced MPA-Au NPs aggregation in the presence of 2,6-pyridinedicarboxylic acid (PDCA) and H(2)O(2) induced fluorescence quenching of 11-MUA-Au NDs. PDCA-Hg(2+)-MPA coordination is responsible for Au NPs aggregation, while the formation of 11-MUA disulfide compounds that release into the bulk solution is responsible for H(2)O(2)-induced fluorescence quenching. In addition to providing information about the chemical structures, SALDI-MS is also selective and sensitive for the detection of Hg(2+) ions and H(2)O(2).

Quantification of captopril in urine through surface-assisted laser desorption/ionization mass spectrometry using 4-mercaptobenzoic acid-capped gold nanoparticles as an internal standard.

We have developed a new internal standard method for the determination of the concentration of captopril (CAP) through surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using gold nanoparticles (Au NPs). This approach provided linearity for CAP over the concentration range 2.5-25 microM (R(2) = 0.

Accurate quantitation of glutathione in cell lysates through surface-assisted laser desorption/ionization mass spectrometry using gold nanoparticles.

We developed a method for the determination of three aminothiols--cysteine, glutathione (GSH), and homocysteine--using surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). The analytes were first captured using the unmodified 14-nm gold nanoparticles; N-2-mercaptopropionylglycine-modified gold nanoparticles serving as internal standard were sequentially added, and then the sample was analyzed using SALDI-MS. This approach provided good quantitative linearity of the three analytes (R(2) = approximately 0.

Determination of perchlorate in river by ion-pair hollow-fiber liquid-phase microextraction coupled with electrospray ionization tandem mass spectrometry.

This paper describes the analysis of perchlorate (ClO(4)(-)) in surface water samples by a rapid and reliable ion-pair hollow-fiber liquid-phase microextraction (HF-LPME) method coupled with flow-injection electrospray ionization tandem mass spectrometry (ESI-MS-MS) technique. The effects of the type and concentration of ion-pairing reagents, extraction time, temperature and pH value on the quantitative extraction of perchlorate by ion-pair HF-LPME were investigated and optimized. Di-n-hexyl ammonium acetate (DHAA) was employed to form an extractable ion-pair complex with aqueous perchlorate.