Microspherical Titanium-Phosphorus Double Oxide: Hierarchical Structure Development for Sensing Applications.

Stable, water-soluble titanium complexed with mandelic acid was used as a precursor for titanium phosphorus double oxide obtained in hydrothermal conditions in the presence of phosphoric acid. Surprisingly, hydrolysis of organic complexes provided a microstructured sphere with narrow size distribution, low aggregation and a small fraction of morphological irregularities. Obtained microspheres had a complex structure comprised of flakes, whose size could be manipulated with temperature conditions.

A novel electrochemical sensor for the detection of fipronil and its toxic metabolite fipronil sulfone using TiO-polytriazine imide submicrostructured composite as an efficient electrocatalyst.

For the first time, a simple and sensitive electrochemical sensor based on a screen printed electrode (SPE) modified with titanium dioxide (TiO) and polytriazine imide submicrostructured composite (TiO-PTI) has been developed for the simultaneous detection of fipronil (FIP) and its toxic metabolite fipronil sulfone (FIP-S). The submicrostructured composite material based on TiO and PTI was obtained by simple hydrothermal treatment of the Ti peroxocomplexes in the presence of pristine. This carbon nitride allotrope has better crystallinity and conductivity than its graphitic analog.

Probing Adsorption of Dipeptides on Anatase in H O and D O: Thermodynamics and Molecular Geometry.

Considering the vast importance of peptide and protein interactions with inorganic surfaces, probing hydrogen bonding during their adsorption on metal oxide surfaces is a relevant task that could shed light on the essential features of their interplay. This work is devoted to studying the dipeptides' adsorption on anatase nanoparticles (ANs) in light and heavy water to reveal differences arising upon the change of the major hydrogen bonding carrier. Thermodynamic study of six native dipeptides' adsorption on ANs in both media shows a strong influence of the solvent on the Gibbs free energy and the effect of side-chain mobile protons on the entropy of the process.

Study of Short Peptide Adsorption on Solution Dispersed Inorganic Nanoparticles Using Depletion Method.

Fundamentals of inorganic-organic interactions are critically important in the discovery and development of novel biointerfaces amenable for utilization in biotechnology and medicine. Recent studies indicate that proteins interact with surfaces through limited adsorption sites. Protein fragments such as amino acids and peptides can be used for interaction modeling between complex biological macromolecules and inorganic surfaces.

Adsorption of Native Amino Acids on Nanocrystalline TiO: Physical Chemistry, QSPR, and Theoretical Modeling.

The affinity of biomolecules, such as peptides and proteins, with inorganic surfaces, is a fundamental topic in biotechnology and bionanotechnology. Amino acids are often used as "model" bits of peptides or proteins for studying their properties in different environments and/or developing functional surfaces. Despite great demand for knowledge about amino acid interactions with metal oxide surfaces, studies on the issue represent a fragmentary picture.

Antiretroviral Drugs-Loaded Nanoparticles Fabricated by Dispersion Polymerization with Potential for HIV/AIDS Treatment.

Highly active antiretroviral (ARV) therapy (HAART) for chronic suppression of HIV replication has revolutionized the treatment of HIV/AIDS. HAART is no panacea; treatments must be maintained for life. Although great progress has been made in ARV therapy, HIV continues to replicate in anatomical and intracellular sites where ARV drugs have restricted access.

Activation of HIV-1 with Nanoparticle-Packaged Small-Molecule Protein Phosphatase-1-Targeting Compound.

Complete eradication of HIV-1 infection is impeded by the existence of latent HIV-1 reservoirs in which the integrated HIV-1 provirus is transcriptionally inactive. Activation of HIV-1 transcription requires the viral Tat protein and host cell factors, including protein phosphatase-1 (PP1). We previously developed a library of small compounds that targeted PP1 and identified a compound, SMAPP1, which induced HIV-1 transcription.

MS-Monitored Conjugation of Poly(ethylene glycol) Monomethacrylate to RGD Peptides.

Development of biologically active polymers is an active area of research due to their applications in varied and diverse fields of biomedical research: cell adhesion, tissue proliferation, and drug delivery. Recent advances in chemical modification allow fine-tuning of the properties of biomedical polymers to improve their applications: blood circulation half-life, stimuli-responsive degradation, site-specific targeting, drug loading, etc. In this article, convergent synthesis of polymerizable macromonomers bearing a site-specific ligand (RGD peptide) using a low molecular weight MA-poly(ethylene glycols) (PEGs) is presented.

S- to N-Acyl transfer in S-acylcysteine isopeptides via 9-, 10-, 12-, and 13-membered cyclic transition states.

S-Acyl cysteine peptides containing α-, β- or γ-amino acid residues undergo long-range S- to N-acyl transfer to give analogs of native tripeptides and tetrapeptides containing additional carbon atoms in the chain. The ease of intramolecular S → N-acyl transfer relative to intermolecular transacylation is favored increasingly for 9 < 12 < 13 ~ 10-membered cyclic transition states; the observed order is explained on conformational and intermolecular interaction considerations.

Traceless chemical ligations from O-acyl serine sites.

Chemical ligation via O- to N-acyl transfer of O-acylated serine containing peptides affords serine containing native peptides via 8- and 11-membered cyclic transition states opening the door to a wide variety of potential applications to peptide elaboration. The feasibility of these traceless chemical ligations is feasible as supported by computation.

Benzotriazol-1-yl-sulfonyl azide for diazotransfer and preparation of azidoacylbenzotriazoles.

Benzotriazol-1-yl-sulfonyl azide, a new crystalline, stable, and easily available diazotransfer reagent provides N-(α-azidoacyl)benzotriazoles convenient for N-, O-, C- and S-acylations. The efficient syntheses of various amides, azido protected peptides, esters, ketones and thioesters is reported together with a wide range of azides (including α-azido acids from α- amino acids in partially aqueous conditions) and diazo compounds.

One-pot synthesis of 5-phenylimino, 5-thieno or 5-oxo-1,2,3-dithiazoles and evaluation of their antimicrobial and antitumor activity.

We here report the synthesis and biological evaluation of rare 4-substituted-5-phenylimino, 5-thieno- and 5-oxo-1,2,3-dithiazoles. Dithiazoles were selectively obtained in moderate to high yields (25-73%) via a one-pot reaction from various ethanoneoximes with sulfur monochloride, pyridine in acetonitrile followed by treatment by corresponding nucleophiles (aniline, thioacetamide and formic acid). All the synthesized compounds were screened for their antibacterial (against bacteria Escherichia coli, Salmonellaenterica serovar Typhimurium, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus and Listeria inocua), antifungal (against pathogenic strains Candida albicans, Candida glabrata, Candida tropicalis and Issatchenkia orientalis) and antitumor (on human cell lines MCF-7 and MDA-MB-231) activity.