Tau biosensor on aptamer-modified interdigitated electrode for monitoring neurological effect caused by anesthesia.

General anesthesia is significantly gaining prominence and becoming unavoidable in modern medicine. Since neuroprotein fluctuations are common during anesthetic procedures, it is essential to monitor protein levels to identify neuro-related issues. Tau protein fluctuations are often found in the anesthetic process, and higher levels of tau are highly related to various neuro-related issues.

Conversion of failed proximal femoral nail antirotation to uncemented or cemented femoral component fixation: a multicentre retrospective study with a median 10-year follow-up.

Background: Conversion of a failed proximal femoral nail antirotation (PFNA) to a total hip arthroplasty (THA) is becoming increasingly universal. However, consensus has not been reached regarding which device (uncemented or hybrid THA) to use. The aim of this retrospective study was to compare the clinical outcomes of the conversion of failed PFNAs to uncemented versus hybrid THAs in the elderly population.

Naphthenic acids speciation and removal during petroleum-coke adsorption and ozonation of oil sands process-affected water.

The Athabasca Oil Sands industry produces large volumes of oil sands process-affected water (OSPW) as a result of bitumen extraction and upgrading processes. Constituents of OSPW include chloride, naphthenic acids (NAs), aromatic hydrocarbons, and trace heavy metals, among other inorganic and organic compounds. To address the environmental issues associated with the recycling and/or safe return of OSPW into the environment, water treatment technologies are required.

Polar stationary phases for capillary electrochromatography.

This review article summarizes the variety of polar stationary phases that have been employed for capillary electrochromatographic separations. Compared with reversed-phase stationary phases, the polar alternatives provide a completely different retention selectivity towards polar and charged analytes. Different types of polar stationary phases are reviewed, including the possible retention mechanisms.

Monolithic columns with mixed modes of reversed-phase and anion-exchange stationary phase for capillary electrochromatography.

A capillary electrochromatography (CEC) monolithic column with mixed modes of reversed-phase and anion-exchange stationary phases was prepared by in situ polymerization of 2-(methacryloxy)ethyltrimethylammonium methyl sulfate (MEAMS) and ethylene dimethacrylate (EDMA) in a binary porogenic solvent consisting 1-propanol and 1,4-butanediol. The ammonium groups on the surface of the stationary phase generate an electroosmotic flow (EOF) from cathode to anode, and serve as a strong anion-exchange stationary phase at the same time. The EOF of the stationary phase can be determined by the amount of MEAMS monomer in reaction mixtures during the polymerization.

Monolithic column with zwitterionic stationary phase for capillary electrochromatography.

A capillary electrochromatography (CEC) monolithic column with zwitterionic stationary phases was prepared by in situ polymerization of butyl methacrylate, ethylene dimethacrylate, methacrylic acid, and 2-(dimethyl amino) ethyl methacrylate in the presence of porogens. The stationary phases have zwitterionic functional groups, that is, both tertiary amine and acrylic acid groups, so the ionization of those groups on the zwitterionic stationary phase was affected by the pH values of the mobile phase, and further affects the strength and direction of the electroosmotic flow (EOF). Separations of alkylbenzenes and polycyclic aromatic hydrocarbons based on the hydrophobic mechanism were obtained.

Separation and identification of compounds in Rhizoma chuanxiong by comprehensive two-dimensional liquid chromatography coupled to mass spectrometry.

A comprehensive two-dimensional liquid chromatographic separation system based on the combination of a CN column and an ODS column is developed for the separation of components in a traditional Chinese medicine (TCM) Rhizoma chuanxiong. Two columns are coupled by a two-position, eight-port valve equipped with two storage loops and controlled by a computer. The effluent is detected by both the diode array detector and atmospheric pressure chemical ionization (APCI) mass spectrometer.

Determination of basic pharmaceuticals in human serum by hydrophilic interaction capillary electrochromatography.

Hydrophilic interaction capillary electrochromatography (HI-CEC) for the determination of basic pharmaceuticals spiked in human serum is described. The organic modifier content, ionic strength, and pH value of the mobile phase as well as the applied voltage are optimized for separation and elution of these drug analytes. Excellent separation was achieved for drugs using a mobile phase composition of 80% v/v acetonitrile in 100 mM triethylamine phosphate (TEAP) buffer at pH 2.

Optimized preparation of poly(styrene-co- divinylbenzene-co-methacrylic acid) monolithic capillary column for capillary electrochromatography.

Preparation of a poly(styrene-co-divinylbenzene-co-methacrylic acid) monolithic stationary phase for the use in capillary electrochromatography (CEC) has been improved by optimizing the polymerization conditions. It is observed that the reaction time strongly affects column efficiency, while the proportion of isooctane in porogen influences peak symmetry of some solutes seriously. The lifetime of the monolithic columns prepared mainly depends on the pH of buffers used.

Peptide separation in hydrophilic interaction capillary electrochromatography.

Separation of small peptides by hydrophilic interaction capillary electrochromatography (HI-CEC) has been investigated. The negative surface charge of a hydrophilic, strong-cation-exchange stationary phase (PolySULFOETHYL A) provided a substantial cathodic electroosmotic flow (EOF). The influence of acetonitrile content, ionic strength, mobile phase pH as well as applied voltage on the migration of the peptides was studied.

The separation of biomolecules using capillary electrochromatography.

The unique properties of capillary electrochromatography such as high performance, high selectivity, minimum consumption of both reagents and samples, and good compatibility with mass spectrometry make this technique an attractive one for the analysis of biomolecules including peptides, proteins, carbohydrates, nucleosides and nucleotides. Irreversible adsorption between the biomolecules and the charged packing surface leads to a lack of reproducibility and serious peak tailing, so various approaches have been taken to overcome this and to improve the technique for future challenges.

Separation of peptides on mixed mode of reversed-phase and ion-exchange capillary electrochromatography with a monolithic column.

The mixed mode of reversed phase (RP) and strong cation-exchange (SCX) capillary electrochromatography (CEC) based on a monolithic capillary column has been developed. The capillary monolithic column was prepared by in situ copolymerization of 2-(sulfooxy)ethyl methacrylate (SEMA) and ethylene dimethacrylate (EDMA) in the presence of porogens. The sulfate group provided by the monomer SEMA on the monolithic bed is used for the generation of the electroosmotic flow (EOF) from the anode to the cathode, but at the same time serves as a SCX stationary phase.