Label-Free Electrochemical Biosensors for the Determination of : Dengue, Zika, and Japanese Encephalitis.

A highly effective way to improve prognosis of viral infectious diseases and to determine the outcome of infection is early, fast, simple, and efficient diagnosis of viral pathogens in biological fluids. Among a wide range of viral pathogens, attract a special attention. genus includes more than 70 viruses, the most familiar being dengue virus (DENV), Zika virus (ZIKV), and Japanese encephalitis virus (JEV).

Electrochemical immunoassay for the detection of antibodies to tick-borne encephalitis virus by using various types of bioconjugates based on silver nanoparticles.

This work reports for the first time a significantly improved and simplified electrochemical immunoassay to detect antibodies to tick-borne encephalitis virus (TBEV) using a 96-well microtiter plate as a platform for immobilization and silver nanoparticles (AgNPs) as electrochemical labels. The electrochemical assay is performed by detecting the elemental silver oxidation signal where the electroactive signalling silver species are released from the bioconjugates (Ab@AgNP, Ab@AgNP, and ProteinA@AgNP). For this purpose, AgNPs were synthesized and further tagged with biomolecules (antibodies to TBEV, cleaved antibodies to TBEV, and protein A).

Dihydrogen Bond in the Aminoborane Complex of a Nicergoline Intermediate.

An aminoborane side product from the nicergoline manufacture process was identified by single-crystal X-ray diffraction. As boranes of pharmaceutical molecules are quite rare, the binding potential of the BH group was investigated and compared with similar compounds using Cambridge Structural Database (CSD). Surprisingly, the packing was stabilized by a dihydrogen bond, which triggered a false alert for too-short contact of hydrogen atoms in IUCR checkCIF.

Preparation and Investigation of Silver Nanoparticle⁻Antibody Bioconjugates for Electrochemical Immunoassay of Tick-Borne Encephalitis.

A new simple electrochemical immunosensor approach for the determination of antibodies to tick-borne encephalitis virus (TBEV) in immunological products was developed and tested. The assay is performed by detecting the silver reduction signal in the bioconjugates with antibodies (). Here, signal is read by cathodic linear sweep voltammetry (CLSV) through the detection of silver chloride reduction on a gold-carbon composite electrode (GCCE).

Electrochemical nonenzymatic sensor for cholesterol determination in food.

The treatment of some inborn metabolism errors requires cholesterol substitution therapy. Cholesterol plays a vital role in the human body. Therefore, the majority of cholesterol determination techniques are targeted to blood and blood serum.

Solid Forms of Tenofovir Disoproxil Fumarate, Their Mutual Conversion, and Stabilization of Form I in Formulation.

Tenofovir disoproxil fumarate (TDF, form I) is an orally delivered pharmaceutical salt used for the treatment of HIV and chronic hepatitis, which acts as an inhibitor of nucleotide reverse transcriptase. There are many solid forms of TDF described in the literature; 2 of them were identified in the drug products: form I and form A. It seems that during formulation, the active pharmaceutical ingredient undergoes partial to total conversion of TDF form I to TDF form A.

Erratum: Capecitabine from X-ray powder synchrotron data. Corrigendum.

[This corrects the article DOI: 10.1107/S1600536809017905.].

Hot-stage microscopy for determination of API fragmentation: comparison with other methods.

Although the fragmentation of the active pharmaceutical ingredient (API) is a phenomenon that is mentioned in many literature sources, no well-suited analytical tools for its investigation are currently known. We used the hot-stage microscopy method, already presented in our previous work, and studied the real fragmentation of the tadalafil particles in model tablets which were prepared under different compaction pressures. The morphology, spectral imaging and evaluation of plastic and elastic energies were also analyzed to support the hot-stage method.

Hot-stage microscopy for determination of API particles in a formulated tablet.

Although methods exist to readily determine the particle size distribution (PSD) of an active pharmaceutical ingredient (API) before its formulation into a final product, the primary challenge is to develop a method to determine the PSD of APIs in a finished tablet. To address the limitations of existing PSD methods, we used hot-stage microscopy to observe tablet disintegration during temperature change and, thus, reveal the API particles in a tablet. Both mechanical and liquid disintegration were evaluated after we had identified optimum milling time for mechanical disintegration and optimum volume of water for liquid disintegration.

The feasibility of automated online flow cytometry for in-situ monitoring of microbial dynamics in aquatic ecosystems.

Fluorescent staining coupled with flow cytometry (FCM) is often used for the monitoring, quantification and characterization of bacteria in engineered and environmental aquatic ecosystems including seawater, freshwater, drinking water, wastewater, and industrial bioreactors. However, infrequent grab sampling hampers accurate characterization and subsequent understanding of microbial dynamics in all of these ecosystems. A logic technological progression is high throughput and full automation of the sampling, staining, measurement, and data analysis steps.

Regio- and stereocontrolled synthesis of novel steroidal isoxazolines: a new route to the formation of selectively modified steroid side chains.

1,3-Dipolar cycloaddition reaction of acetonitrile oxide to cis- and trans-22-hydroxy-24-alkoxycarbonyl-Δ(23)-steroids is investigated. An unusual stereochemical course of the cycloaddition, leading to the same set of the isoxazoline adducts for both (Z)- and (E)-disubstituted olefins is revealed. It is shown, the reaction is regioselective and all possible 4',5'-diastereoisomers of resulting isoxazolines can be prepared as major products by cycloaddition to the suitable alkene.

A new way of solid dosage form samples preparation for SEM and FTIR using microtome.

Rapid and correct production of generic solid dosage forms requires a large amount of analytical data and conclusions. Modern analytical techniques have a good resolution and accuracy and allow obtaining a lot of information about the original product. Scanning electron microscopy (SEM) is used for observation and assessing individual layers, core and surface of solid dosage forms.

Characterizing crystal disorder of trospium chloride: a comprehensive,(13) C CP/MAS NMR, DSC, FTIR, and XRPD study.

Analysis of C cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), and X-ray powder diffraction data of trospium chloride (TCl) products crystallized from different mixtures of water-ethanol [φ(EtOH) = 0.5-1.0] at various temperatures (0°C, 20°C) and initial concentrations (saturated solution, 30%-50% excess of solvent) revealed extensive structural variability of TCl.

[Atypical pain in the uterine rupture].

Objective: To give attention to the rare complication of pregnancy.

Design: Case report.

Settings: Dept.

Selective trapping and manipulation of microscale objects using mobile microvortices.

Controlled manipulation of individual micro- and nanoscale objects requires the use of trapping forces that can be focused and translated with high spatial and time resolution. We report a new strategy that uses the flow of mobile microvortices to trap and manipulate single objects in fluid with essentially no restrictions on their material properties. Fluidic trapping forces are generated toward the center of microvortices formed by magnetic microactuators, that is, rotating nanowire or self-assembled microbeads, actuated by a weak rotating magnetic field (|B|< 5 mT).

Steerable intravitreal inserts for drug delivery: in vitro and ex vivo mobility experiments.

The progress of wet age-related macular degeneration can now be controlled by intravitreal drug injection. This approach requires repeated injections, which could be avoided by delivering the drug to the retina. Intraocular implants are a promising solution for drug delivery near the retina.

A new polymorph of succinylcholinium diiodide: comparison of succinylcholinium structures.

The title compound {systematic name: trimethyl[2-({4-oxo-4-[2-(trimethylazaniumyl)ethoxy]butanoyl}oxy)ethyl]azanium diiodide}, C(14)H(30)N(2)O(4)(2+)·2I(-), is a salt of the succinylcholinium cation. There is one formula unit in the asymmetric unit, represented by two anions and two halves of two cations which lie on centres of inversion. The component species are stabilized by electrostatic interactions, and C-H···I and C-H···O hydrogen bonds are also present.

Controlled propulsion and cargo transport of rotating nickel nanowires near a patterned solid surface.

We show that rotating Ni nanowires are capable of propulsion and transport of colloidal cargo near a complex surface. When dissimilar boundary conditions exist at the two ends of a nanowire, such as when a nanowire is near a wall, tumbling motion can be generated that leads to propulsion of the nanowire. The motion of the nanowire can be precisely controlled using a uniform rotating magnetic field.

Image-based 3D reconstruction using helical nanobelts for localized rotations.

A variety of different methods exist for gathering three-dimensional information for micro- and nanoscale objects. Tilting of samples in a scanning electron microscope provides a non-destructive way of generating these data. Traditionally, the reconstruction of this image data is performed by stereo photogrammetric methods that compare features from two or three frames.

Alaptide from synchrotron powder diffraction data.

THE TITLE COMPOUND [SYSTEMATIC NAME: (8S)-8-methyl-6,9-diaza-spiro-[4.5]decane-7,10-dione], C(9)H(14)N(2)O(2), consists of two connected rings, viz. a piperazine-2,5-dione (DKP) ring and a five-membered ring.

Characterizing the swimming properties of artificial bacterial flagella.

Artificial bacterial flagella (ABFs) consist of helical tails resembling natural flagella fabricated by the self-scrolling of helical nanobelts and soft-magnetic heads composed of Cr/Ni/Au stacked thin films. ABFs are controlled wirelessly using a low-strength rotating magnetic field. Self-propelled devices such as these are of interest for in vitro and in vivo biomedical applications.

Capecitabine from X-ray powder synchrotron data.

In the title compound [systematic name 5-de-oxy-5-fluoro-N-(pent-yloxycarbon-yl)cytidine], C(15)H(22)FN(3)O(6), the pentyl chain is disordered over two positions with refined occupancies of 0.53 (5) and 0.47 (5).

Methyl-ergometrine maleate from synchrotron powder diffraction data.

The title compound {systematic name: 9,10-didehydro-N-[1-(hydroxy-meth-yl)prop-yl]-d-lysergamide maleate}, C(20)H(26)N(3)O(2) (+)·C(4)H(3)O(4) (-), contains a large rigid ergolene group. This group consists of an indole plane connected to a six-membered carbon ring adopting an envelope conformation and N-methyl-tetra-hydro-pyridine where the methyl group is in an equatorial position. In the crystal, inter-molecular N-H⋯O, O-H⋯N and O-H⋯O hydrogen bonds form an extensive three-dimensional hydrogen-bonding network, which holds the cations and anions together.