The use of Fourier transform infrared (FT-IR) and inductively coupled plasma-atomic emission (ICP-AES) spectrometric detectors for liquid (LC) and supercritical fluid (SFC) chromatography is reviewed. While interfacing these detectors with gas chromatography has reached a degree of maturity, the development of such characterization detectors for LC and SFC still present many challenges for analytical chemists. In LC almost all mobile phases strongly absorb over most of the infrared region. Observing and identifying the trace compounds in the presence of the LC mobile phase are the major problems of the LC/FT-IR experiments. The authors have taken two approaches to solve this problem. One method makes use of deuterated solvents as the mobile phase of microcolumn LC. This allows monitoring of several important absorption regions with a flow cell. The second method involves continuous deposition of the total effluent from a microcolumn on a moving substrate (a KBr plate or a stainless-steel wire net) while the mobile phase is evaporated instantaneously under a stream of heated nitrogen. After the separation is complete, the substrate is moved again into the beam condenser optics of an FT-IR spectrometer to obtain infrared spectra of the eluites deposited on it. This interface enables both chromatographic and spectroscopic measurements of trace compounds. Additional possibilities of this technique include: (a) further characterization by other spectrometric methods; (b) LC/thin-layer chromatography(TLC)/FT-IR experiments by using a TLC plate as the substrate; and (c) extension of this technique to SFC. The compatibility of standard LC flow rates with pneumatic nebulization in ICP plasma and plasma stability in the aqueous mobile phase has led to interfacing of ICP-AES with LC in several laboratories. However, coupling of regular column LC with the plasma source is hampered by the inherent instability of the plasma to many of the organic solvents used in LC. The first approach which the authors have adopted is to employ a simple tee to connect the outlet of a microcolumn to a normal sample introduction tube in a conventional cross-flow spray chamber. Through one port of the tee the total column effluent is carried into the spray chamber together with an auxiliary solvent being aspirated through the other port of the tee. This approach exhibited several problems, such as loss in chromatographic resolution and poor sensitivity. These problems were overcome by using a plasma torch connected directly to a cross-flow nebulizer. The microcolumn LC effluent is aspirated through a capillary which is inserted into the sample uptake tube of the nebulizer. This detection system was successfully used for element-selective detection of various species even when organic solvents were employed as the mobile phase. A nebulizer with a built-in glass capillary restrictor was used for SFC/ICP-AES experiments.

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The influences of achiral factors upon the retention and enantioselectivety of N-3, 5-dinitrobenzoyl derivatives of baclofen (4-amino-3-p-chlorophenylbutyric acid), a skeletal muscle relaxant, and DP-1904, a novel thromboxane A2 synthetase inhibitor, using three kinds of chiral stationary phases (long alkyl spacer-; LA-, short alkyl spacer-; SA- and helical-; Hel- type CSPs) have been examined. Mobile phases of organic solvent-aqueous phosphate buffer were used and the effects of organic solvent concentration, pH and the addition of achiral ion-pairing agents were studied. As a result, optimum ranges of enantioselectivities occured at each pH and contents of organic solvents except for short alkyl chain spacer type CSP. And we observed a linear relationship between the contents of organic solvents and In k' (k'=capacity factor). In the case of LA-CSP, the addition of achiral ion-pairing reagents (alkyltrimethylammonium phosphate) was effective. The increase in the concentration and the chain length of alkyl portion of the ion-pairing reagent gave increased retention and enantioselectivity for N 3, 5-dinitrobenzoyl derivatives of baclofen on LA-CSP. These results suggest that enantiomeric separation using HPLC can be improved by achiral factors.

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The commercially available molybdenum metals, including a rod (Jhonson Matthey batch No. 31825) of high purity, were analyzed for their trace impurities by using a VG9000 glow discharge mass (GD-MS) spectrometer equipped with a highly sensitive glow discharge cell, the so-called“Mega cell”, and a liq. N₂ sample cooling system. The samples, mechanically shaped in rod form (2.3 mm × 2.3 mm × 22 mm or 2.02.3 mm in diameter and 20 mm in length), were washed with aqua regia and deionized water, and then dried just before use. Preliminary sputtering in the glow discharge cell was required for surface cleaning of the sample: 30 min for the determination of most elements and 2 h for C, O and Cl at ppb level. The discharge current was fixed to 3.0 mA and the discharge voltage was controlled at 1.00 ± 0.05 kV for the determination. Most of the elements at ppm level could be determined with a RSD of 3% or less. However, the determination of titanium was quite difficult because the overlap of doubly charged Mo ions on all isotopes of singly charged Ti ion is unavoidable under the adopted resolution of 4000 or a little higher. For the typical 16 elements which could be determined by ICP-AES, furnace AAS etc., the analytical values obtained by GD-MS were in good or reasonable agreement with those by other methods except for C, O and ppbppt levels of U and Th. These results suggest that the VG recommended relative sensitivity factor used in this work is applicable to the analysis of high purity molybdenum metals.

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In order to expand solution chemiluminescence (CL) analysis in organic solvents, an organic solvent carrier system applicable to FIA was developed and applied to the CL determination for tetrahydrofuran (THF). The carrier system is protected from destruction by organic solvents by a joint to another water introduction line. The proposed FIA/CL system is comprised of three flow lines; the CH₃CN solution line for CL reagents equipped with a light introduction system, the sample solution line and the protection line. The CL for the THF determination is essentially produced by the reaction between THF and the methylsilicone solid polymer used for the flow cell and enhanced with dyesensitizer, surfactant and visible light. Since the CL is weakly and slowly produced, THF is determined by the stopped flow method. The lower detection limit is 1× 10 ^-3 M by the continuous sample flow method. Relative standard deviation is 6.2% for 7 repeated runs of the 1 M THF solution. Sampling rate is 72 per hour. In terms of relative error, the samples containing 10 v/v% of toluene, cyclopentane or 1, 2, 4-trimethylbenzene in 1 M THF showed 100% interference of the CL intensity for 1 M THF alone.

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Mass spectra of various thioimidate-ester salts such as adducts of thioamide or thiourea derivative and alkylbromide were measured by fast atom bombardment (FAB) mass spectrometry. The FAB mass spectra provided structural information concerning the cation part of the thioimidates. The spectra gave an intense peak corresponding to the intact iminium ion [M-Br]⁺ as the base peak and some fragment ions in almost all cases. The main fragmentation pathway of the intact iminium ion is cleavage at the carbon-sulfur bond of the alkylthio group to give the corresponding protonated thioamide ions, followed by the thiocarbonyl carbon-nitrogen bond cleavage giving the isothiocyanato cations. The composition of the intact iminium ion and some characteristic fragment ions were determined by high resolution FAB mass spectrometry. Since the spectral patterns are fully reproducible, FAB mass spectrometry is applicable to structural analysis of thioimidates.

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The ordinary Bimetal is composed of two metal plates which expand at different rates with temperature change. By using a principle similar to the Bimetal, we have developed a new“Chemical Bimetal”, which consists of the combination of two kinds of polymer plates having different chemical or physico chemical behavior. In this report, the fundamental characteristics of hydroxide ion sensitive Chemical Bimetal have been investigated. One plate is insensitive to hydroxide ion. Another plate contains a substance reactive to hydroxide ion. Therefore, the Chemical Bimetal curves according to the hydroxide ion concentration of a dip solution. The Chemical Bimetal consists of a reaction film, which is made from 20% pelargonic acid, 40% dioctyl phthalate (DOP) and 40% polyvinyl chloride (PVC), and a polyester film. This chemical bimetal responded to the hydroxide ion concentration and showed a nearly linear response to the sodium bicarbonate solution from 0.005 to 0.04 N. The change in position was 13 mm in 0.02 N sodium hydroxide solution. Fundamental studies on composition, plate thickness, production methods, and reaction mechanisms of the Chemical Bimetal were performed. This Chemical Bimetal was found to be useful as a hydroxide ion sensor.

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A gas-phase sample introduction technique has been developed in order to improve the sensitivity in the determination of sulfur in aqueous solution by ICP-AES. This technique is based on the reduction of sulfate ion by a sodium iodide, hydroiodic acid and hypophosphorous acid reducing mixture followed by the evolution of hydrogen sulfide which is carried by argon gas into the plasma via a gas-liquid separator. The reaction is achieved in a path which leads to the plasma torch. The path consists of Teflon reaction tube (1.4 mm i.d., 2.0 mm o.d. × 200 cm) and gas-liquid separator connected to the plasma torch through tubing. The path is partially heated at 135°C to reduce sulfate ion to hydrogen sulfide. The test solution, the reducing mixture and argon gas are continuously led into the path from different inlets. The heating temperature of the reaction tube must be kept constant because any changes in it influence the emission intensity. The efficiency of sample introduction into the plasma was 59% for 2 M hydrochloric acid media. Iron(III), nickel(II), cobalt(II) and gallium(III) as matrix components (30 or 50 gl^-1 ) had no influence on the emission intensity at S I 180.73 nm while copper(II) (10 gl^-1) reduced the emission intensity by 10%. Nitric acid reduced the emission intensity. Phosphoric acid had no influence. Relative standard deviation was 1.4% for the potassium sulfate solution (50 ngS ml ^-1 in 2 M hydrochloric acid) and the detection limit was 3.4 ngS ml ^-1. This technique was applied to the determination of sulfur in steel samples and gallium phosphide crystals. The results for steel samples showed good agreement with the certified values. And the results for gallium phosphide crystals showed good correlation between the present method and glow discharge mass spectrometry.

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Carboxylated microspheres were synthesized by seeded emulsion polymerization of methacrylic acid, n-butylacrylate and styrene. The features of the microspheres such as composition, average particle diameter and particle distribution were examined by elemental analysis, FT-IR spectrum, particle grading analysis and scanning electron micrography. The manner of adsorption onto these microspheres in water suspension was studied for the metals Cu(II), Zn(II), Co(II), Ni(II) and Mn(II). The adsorption equilibrium was attained in less than 1 h. The microspheres could adsorb Cu(II) and Zn(II) selectively from weakly acidic solution (pH 5.6). The selectivity for Cu(II) among the divalent metal ions was comparable to those reported with Cu(II)-templated polymer resins.

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In life science research, the distribution of intracellular free calcium ion concentration ([Ca²⁺]_i) is widely done using a fluorescent indicator dye such as Fura-2, Indo-1. Of particular interest is correspondence between [Ca²⁺]_i distribution and cellular structure. This report describes a system for superimposition of [Ca²⁺]_i distribution and cellular microscopic images made with transmitted light or Nomarski differential interference. This system uses the instrumentation described in the previous report but with improved the computer software. The superimposed image shows 24 colors for [Ca²⁺]_i and 7 levels of black-and-white in the microscopic image. [Ca²⁺]_i images of NG108-15 corresponded well with transmitted light image of microscope. However, the [Ca²⁺]_i and differential interference image differed by parallel shift, rotation and magnification cause by insertion of the Nomarski prism, etc. in imcroscopic light path. The superimposed image was particularly affected by parallel shift. The parallel translation of microscopic images was included in the image processing program in order to bring the image into correspondence.

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The distribution of intracellular free calcium ion concentration ([Ca²⁺]_i) is measured using a fluorescent calcium indicator dye and video fluorescence microscope. In many cases, the [Ca²⁺]_i distribution around cells is unusually concentration. This well-known phenomenon is due to the halation from the fluorescent cell images. The [Ca²⁺]_i distribution containing the halation is usually calculated by a conventional background estimation method. In the improved method, three types of background fluorescence intensity are distinguished. Two types are the same as the conventional background intensity. The third is halation intensity. The estimation of halation intensity is performed as follows. The first step is the display of superimposed fluorescent image and cell image obtained by transmitted light microscopy. The second step specifies the halation intensity by the fluorescence intensity at the edge of the cell. The [Ca²⁺]_i distribution is calculated only from that fluorescent intensity which exceeds the halation intensity. By this improved estimation method, the [Ca²⁺]_i distribution correspondence to the microscopic cell images could be obtaind.

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