Measurement of atmospheric amines and aminoamides by column adsorption/extraction and hydrophilic liquid chromatography-electrospray-tandem mass spectrometry.

Sampling and chromatography-mass spectrometry methods were investigated to measure atmospheric amines and aminoamides. Amines and their amide derivatives play significant roles in new particle formation (NPF) in the atmosphere, especially diamines and aminoamides have higher NPF potentials compared to monoamines. For amine sampling, silica gel tube collection and formic acid extraction gave good overall recoveries (>93 ± 8%) for mono-, di-, tri-, tetramines, and aminoamides.

Two-step extraction for the evaluation of metal-organic framework impregnated materials.

Metal-organic frameworks (MOFs) are widely used for gas adsorption, separation, and sensing materials. In most cases, MOFs are not used in their crystal form but as impregnated materials because the fine crystals result in high-pressure drops. One key characteristic of MOF-impregnated materials is the amount of MOF in the material.

Abundant production of dimethylsulfoniopropionate as a cryoprotectant by freshwater phytoplanktonic dinoflagellates in ice-covered Lake Baikal.

Phytoplanktonic dinoflagellates form colonies between vertical ice crystals during the ice-melting season in Lake Baikal, but how the plankton survive the freezing conditions is not known. Here we show that the phytoplankton produces large amounts of dimethylsulfoniopropionate (DMSP), which is best-known as a marine compound. Lake-water DMSP concentrations in the spring season are comparable with those in the oceans, and colony water in ice exhibits extremely high concentrations.

Radioactive isotope separation with 3D-printed flow-based device.

Radioactive isotope (RI) metals are a new type of tracer for positron emission tomography generated from the target metal by proton irradiation using a cyclotron. The generated metal RIs need to be separated from the target metal rapidly and effectively. In the present study, we developed a 3D-printed flow device to separate metal RIs from target metals.

Electrodialytic Universal Synthesis of Highly Pure and Mixed Ionic Liquids.

Ionic liquids (ILs) have attracted significant attention from researchers in various fields as a result of their unique properties. As new and important applications are identified for these materials, there is also a drive to develop methods for accessing a wider range of ILs. However, despite this demand, only a few techniques have so far been reported and, more importantly, general but efficient processes for IL synthesis have been lacking.

Highly Efficient Separation of Ultratrace Radioactive Copper Using a Flow Electrolysis Cell.

Preparing compounds containing the radioisotope Cu for use in positron emission tomography cancer diagnostics is an ongoing area of research. In this study, a highly efficient separation method to recover Cu generated by irradiating the target Ni with a proton beam was developed by employing a flow electrolysis cell (FE). This system consists of (1) applying a reduction potential for the selective adsorption of Cu from the target solution when dissolved in HCl and (2) recovering the Cu deposited onto the carbon working electrode by desorbing it from the FE during elution with 10 mmol/L HNO, which applies an oxidation potential.

Electrodialytic Enrichment and Matrix Conversion for the Determination of Trace Metals in Ultra-Pure Water.

The presence of trace contaminants in ultra-pure water (UPW) used in fabrication process can greatly affect the yield and quality of industrial products. In the present study, the electrodialytic enrichment of metal cations as a means of continuously monitoring the UPW quality was studied. A newly designed electrodialytic enrichment device (EED) was used to quantitatively transfer metal ions from samples to dilute nitric acid, which was then directly introduced into an inductively coupled plasma-mass spectrometry (ICP-MS) instrument.

Rapid Flow-Based System for Separation of Radioactive Metals by Selective Complex Formation.

Short-lived radioactive metals are important tracers in clinical diagnosis. Radioactive metals for clinical use are produced from suitable target metals in cyclotrons. The trace amount of radioactive metal produced is contained in a relatively large amount of target metal.

Indirect Potentiometric pH Detection of Weak Acids with Absolute Quantitation by a Theoretical Approach.

A fast response potentiometric flow-through pH sensor was applied for organic acid determination. The analyte response with the pH sensor was obtained by eluent pH modification following ion exclusion chromatography with HClO as an eluent. The response characteristics depend on the adjusted baseline pH.

Natural dimethyl sulfide gradients would lead marine predators to higher prey biomass.

Finding prey is essential to survival, with marine predators hypothesised to track chemicals such as dimethyl sulfide (DMS) while foraging. Many predators are attracted to artificially released DMS, and laboratory experiments have shown that zooplankton grazing on phytoplankton accelerates DMS release. However, whether natural DMS concentrations are useful for predators and correlated to areas of high prey biomass remains a fundamental knowledge gap.

Measurement Device for Ambient Carbonyl Sulfide by Means of Catalytic Reduction Followed by Wet Scrubbing/Fluorescence Detection.

A portable chemical analysis system for monitoring ambient carbonyl sulfide (COS) was investigated for the first time. COS is paid attention to from the perspectives of photosynthesis tracer, breath diagnosis marker, and new process-use in the manufacture of semiconductors. Recently, the threshold level value of COS was settled at 5 ppm in volume ratio (ppmv) for workplace safety management.

Electrodialytic Handling of Radioactive Metal Ions for Preparation of Tracer Reagents.

Radioactive metals are applied in biochemistry, medical diagnosis such as positron emission tomography (PET), and cancer therapy. However, the activity of radioisotopes exponentially decreases with time; therefore, rapid and reliable probe preparation methods are strongly recommended. In the present study, electrodialytic radioactive metal ion handling is studied for counter ion conversion and in-line probe synthesis.

Miniaturized crossflow ion transfer device for post-column enrichment in ion chromatography.

The sensitivity of an ion chromatography system was improved using electrodialytic post-column enrichment. Even though post-column reactions, such as suppression, have been used to enhance the sensitivity, there are only a few methods available to increase the concentration and improve the sensitivity. Post-column in-line enrichment was achieved with a miniaturized crossflow ion transfer device (ITD) prepared in our laboratory.

Semi-continuous Monitoring of Cr(VI) and Cr(III) during a Soil Extraction Process by Means of an Ion Transfer Device and Graphite Furnace Atomic Absorption Spectroscopy.

Electrodialytic separation of Cr(VI) and Cr(III) followed by graphite furnace atomic absorption spectrometry for monitoring of soil extraction was studied. The sensitivity was improved by in-line purification of the solutions and bi-polar pulse cleaning. The detection limit for both Cr(VI) and Cr(III) was 0.

High Sensitivity Monitoring Device for Onboard Measurement of Dimethyl Sulfide and Dimethylsulfoniopropionate in Seawater and an Oceanic Atmosphere.

An automated device has been developed to measure aqueous dimethyl sulfide (DMSaq), its precursor dimethylsulfoniopropionate (DMSP), and atmospheric gaseous dimethyl sulfide (DMSg). In addition to having a role in the oceanic atmosphere, DMS and DMSP have recently gained substantial interest within the biosciences and are suspected as chemoattractants for predators searching for prey. To provide the spatial resolution relevant for biogeochemical functions, fast and on-site analysis of these compounds is an important technique.

Universal HPLC Detector for Hydrophilic Organic Compounds by Means of Total Organic Carbon Detection.

Most quantifications are achieved by comparison of the signals obtained with the sample to those from a standard. Thus, the purity and stability of the standard are key in chemical analysis. Furthermore, if an analyte standard cannot be obtained, quantification cannot be achieved, even if the chemical structures are identified by a qualification method (e.

Ultra-sensitive Trace-Water Optical Sensor with In situ- synthesized Metal-Organic Framework in Glass Paper.

Monitoring of trace water in industrial gases is strongly recommended because contaminants cause serious problems during use, especially in the semiconductor industry. An ultra-sensitive trace-water sensor was developed with an in situ-synthesized metal-organic framework as the sensing material. The sample gas is passed through the sensing membrane and efficiently and rapidly collected by the sensing material in the newly designed gas collection/detection cell.

Electrodialytic extraction of anionic pharmaceutical compounds from a single drop of whole blood using a supported liquid membrane.

A method to introduce target analytes to a chromatograph from a single drop of whole blood was investigated for minimally invasive monitoring of anionic pharmaceuticals. In this work, salicylate and loxoprofen were examined as organic anions. A micro ion extractor (MIE) has been developed for extraction of inorganic trace anions from whole blood, but this device is not suitable for extraction of pharmaceuticals.

Electrodialytic in-line preconcentration for ionic solute analysis.

Preconcentration is an effective way to improve analytical sensitivity. Many types of methods are used for enrichment of ionic solute analytes. However, current methods are batchwise and include procedures such as trapping and elution.

Admittance Scanning for Whole Column Detection.

Whole column detection (WCD) is as old as chromatography itself. WCD requires an ability to interrogate column contents from the outside. Other than the obvious case of optical detection through a transparent column, admittance (often termed contactless conductance) measurements can also sense changes in the column contents (especially ionic content) from the outside without galvanic contact with the solution.

Matrix isolation with an ion transfer device for interference-free simultaneous spectrophotometric determinations of hexavalent and trivalent chromium in a flow-based system.

Chromium speciation by spectrophotometric determination of hexavalent chromium (Cr(VI)) with diphenylcarbazide (DPC) has several problems. These include: (1) the inability to directly detect trivalent chromium (Cr(III)) with DPC, (2) positive interference in Cr(VI) determination by other metal cations and (3) negative interference by any reducing agent present in the sample. These are addressed with an ion transfer device (ITD) in a flow injection analysis system.

Monitoring variations of dimethyl sulfide and dimethylsulfoniopropionate in seawater and the atmosphere based on sequential vapor generation and ion molecule reaction mass spectrometry.

To monitor the fluctuations of dimethyl sulfur compounds at the seawater/atmosphere interface, an automated system was developed based on sequential injection analysis coupled with vapor generation-ion molecule reaction mass spectrometry (SIA-VG-IMRMS). Using this analytical system, dissolved dimethyl sulfide (DMS(aq)) and dimethylsulfoniopropionate (DMSP), a precursor to DMS in seawater, were monitored together sequentially with atmospheric dimethyl sulfide (DMS(g)). A shift from the equilibrium point between DMS(aq) and DMS(g) results in the emission of DMS to the atmosphere.

Simultaneous analysis of silicon and boron dissolved in water by combination of electrodialytic salt removal and ion-exclusion chromatography with corona charged aerosol detection.

Selective separation and sensitive detection of dissolved silicon and boron (DSi and DB) in aqueous solution was achieved by combining an electrodialytic ion isolation device (EID) as a salt remover, an ion-exclusion chromatography (IEC) column, and a corona charged aerosol detector (CCAD) in sequence. DSi and DB were separated by IEC on the H(+)-form of a cation exchange resin column using pure water eluent. DSi and DB were detected after IEC separation by the CCAD with much greater sensitivity than by conductimetric detection.