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Volume 40, Issue 5
Displaying 1-11 of 11 articles from this issue
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Terumichi NAKAGAWA, Akimasa SHIBUKAWA1991 Volume 40 Issue 5 Pages 203-214
Published: May 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSHigh-performance frontal analysis (HPFA) is a novel chromatographic method originally developed for the determination of unbound drug concentration in protein binding equilibrium. The present paper deals with the rationale and features of the HPFA method. HPFA uses a "restricted-access "HPLC column which is designed to size-exclude macromolecules such as plasma proteins, but to retain drugs of small molecular size. When a certain excess volume of drug-protein mixed solution is continuously injected to the column with the mobile phase, the protein binding equilibrium, same as that in the sample solution is reproduced in a limited zone near the top of the column. Consequently, the unbound drug is eluted as a zonal peak, being separated from the protein peak. Therefore, the unbound drug concentration can be determined from the plateau height of the drug peak. When the drug peak is completely separated from the protein peak, the total drug concentration can be also determined from the peak area. This is the rationale of the HPFA method. The HPFA method has several features; (i) it does not suffer from the undesirable adsorption of drug to the filter membrane and the leakage of unbound drug from the membrane, which are often encountered in the widely used equilibrium dialysis method and the ultrafiltration method, (ii) it is easy to incorporate HPFA into on-line HPLC systems, (iii) the unbound drug solution of larger volume than the injected sample volume is obtained when the drug is highly bound to protein. HPFA are applied to the simultaneous determination of total and unbound carbamazepine concentrations in human plasma and stereoselective determinations of unbound warfarin and ketoprofen following direct sample injection.View full abstractDownload PDF (1570K) -
Yoshitaka MASUDA, Yoko OKADA, Ichiro MURASE, Eiichi SEKIDO1991 Volume 40 Issue 5 Pages 215-220
Published: May 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSThe complex formation of tetraethylenepentamineheptaacetic acid (TPHA or H7L) or triethylenetetraminehexaacetic acid (TTHA or H6L) or diethylenetriaminepentaacetic acid (DTPA or H5L) with scandium(III) ion was investigated, and the stability constants were determined by potentiometric measurements. In aqueous 0.1M KNO3 solution, four mononuclear TPHA complex species ScH3L-, ScH2L2-, ScHL3- and ScL4- were formed. The binuclear TPHA complexes, Sc2L and Sc2HL, were also formed. The existence of two hydroxo TTHA complexes were indicated by titration data. The order of stability constants of mononuclear complex (log KML) was as follows: Sc(III)-DTPA (20.99)>Sc(III)-TTHA (19.12)>Sc(III)-TPHA (19.04). The lower stability constants of TPHA and TTHA complexes compared to DTPA was thought to be due to the higher number of donor groups in the TPHA and TTHA molecule which were not bound to scandium. It was found that the stability constant of monoprotonated mononuclear TPHA complex is greater than those of DTPA and TTHA. The tendency to form protonated complexes increased as expected with increasing number of carboxylic groups in the molecule. The separation of scandium(III)- and lanthanum(III)-TPHA complex by isotachophoresis is also described in detail. The satisfactory separation of scandium in acetone-water medium (50%v/v) was accomplished by using citric acid as the terminating electrolyte with the leading solution containing 5mM hydrochloric acid, buffered at pH 2.4 with 1mM β-alanine.View full abstractDownload PDF (669K) -
Kiyoshi HASEGAWA, Choichiro SHIMASAKI, Sigeya TAKEUCH, Satomi TANIGAWA ...1991 Volume 40 Issue 5 Pages 221-225
Published: May 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSSaccharides in raw cotton absorb moisture from the air and form adhesives. Adhesive saccharides cause the cotton fiber to be wound on the roller which lowers the quality of the cotton. As the first step to resolve the winding, saccharides in seven raw cottons were determined in detail by a new HPLC/TLC method. The main saccharides which may cause the winding were investigated. Seven raw cottons were extracted with water at 50°C. The saccharides extracted were determined by TLC after HPLC fractionation. Monosaccharide (glucose, fructose, galactose, xylose and arabinose) disaccharide (sucrose, turanose, maltose and isomaltose) and trisaccharide (raffinose and melezitose) were determined. In all the raw cottons, saccharides increased in order of mono->di->trisaccharides and each component of them was very similar. The amounts of saccharides were exceedingly different among the cotton from the different raw cotton-growing districts. Increased amounts of saccharides were determined as follows: Nicaragua>SanJoaquin (USA)>Texas (USA)>Central Asia (USSR)>sinsiang (China)>Pakistan>Australia. The main saccharides which caused problems in the spinning of Nicaragua and San Joaquin cottons were found to be glucose and fructose (monosaccharide), and sucrose and maltose (disaccharide).View full abstractDownload PDF (587K) -
Takashi SAITO1991 Volume 40 Issue 5 Pages 227-231
Published: May 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA new method for colorimetric determination of trace copper ion has been studied using a polyvinyl chloride (PVC) membrane containing 4, 7-dipheny1-2, 9-dimethy1-1, 10-phenanthroline (bathocuproine) and o-nitrophenyloctylether (ο-NPOE). A 5 cm3 of aqueous sample containing copper ions was placed in a glass sample tube (30cm3 volume), and 0.5cm3 of 6.5×10-2mol dm-3 hydroxylammonium sulfate, 0.13mol dm-3 potassium chloride and acetic acid-sodium acetate buffer (pH 5.9) was added. A sheet of PVC membrane consisting of 0.7wt% bathocuproine and 65.0wt% ο-NPOE was put into the solution and stirred with a magnetic stirrer for a definite time at 60°C. The membrane removed from the solution was rinsed with small amount of water, and wiped to remove the water droplets. The absorbance of the colored membrane was measured at 480nm by spectrophotometer, and the copper ion concentration in the sample solution was determined using a calibration curve. The determination range of copper ion was 1.50×10-7 to 4.29×10-5mol dm-3. The reproducibility was 0.361±8.59×10-3 at2.4% of RSD (n=10) for the sample containing 1.07×10-7mol dm-3 of copper ion.View full abstractDownload PDF (565K) -
Toshio HIRAI, Masataka KITAMURA, Yoshinori INOUE1991 Volume 40 Issue 5 Pages 233-238
Published: May 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA novel isoprenoid derivative N-solanesyl-N, N'-bis(3, 4-dimethoxybenzyl) ethanediamine (SDB), weak fluorescence compound having secondary amino group in the molecule, is an anti-tumor activity potentiating agent for a variety of anti-tumor agents, e.g., adriamycin, 5-fluorouracil and mitomycin C. A precolumn fluorescence labeling reagent was investigated for a highly sensitive detection method of SDB by HPLC. SDB was converted into its urea derivatives using three kinds of activated carbamate reagents synthesized from N, N'-disuccinimidyl carbonate by reacting with α-naphthylamine (α-NA), 2-aminoanthracene (2-AT) or 2-aminofluorene (2-AF) as a fluorescence molecule group. The fluorescence intensities of naphthylcarbamyl and anthrylcarbamyl derivatives of SDB converted by using α-NA and 2-AT were ca. 3-fold and 13-fold compared to that of SDB, respectively. On the other hand, the fluorescence intensity of fluorenylcarbamyl deriva tive of SDB obtained in the reaction with succinimido-2-fluorenylcarbamate (SFC) synthesized by using 2-AF was ca. 45-fold greater than that of SDB. The reaction time was within 5min at room temperature: the reaction mixture could be analyzed directly by means of reversed-phase HPLC using fluorometric detection at 343nm while excited at 286 nm for emission wavelengths. The detection limit was 20pg (S/N=2). SFC facilitated the simple and rapid precolumn derivatization of SDB for the highly sensitive fluorometric detection.View full abstractDownload PDF (790K) -
Toshio HIRAI, Kiyomi UMEZAWA, Masataka KITAMURA, Yoshinori INOUE1991 Volume 40 Issue 5 Pages 239-243
Published: May 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSA novel isoprenoid derivative N-solanesyl-N, N'-bis(3, 4-dimethoxybenzyl) ethanediamine (SDB) is an anti-tumor activity potentiating agent for a variety of anti-tumor agents, e.g., adriamycin, 5-fluorouracil and mitomycin C. A simple and sensitive method for the determination of SDB in serum has been developed by HPLC using precolumn fluorescence labeling reagent succinimido-2-fluorenylcarbamate (SFC). After deproteinization with ethanol, SDB in human serum was extracted with diethylether. Extracted SDB was converted into its fluorenylcarbamyl derivative SDB-FC using SFC in acetonitrile. Reaction was completed within 5min at room temperature. A part of the reaction mixture was injected directly into a HPLC system. HPLC was performed on a reversed-phase TSK Gel ODS-80TM 4.6×250mm column using ethanol: methanol: acetic acid=650: 347.5:2.5v/v containing 0.2% of ammonium acetate as the mobile phase at a flow rate of 1.0ml/min. Eluate from the column was monitored fluorometrically at 343nm while excited at 286 nm. Under these conditions, SDB-FC could be separated completely from the other components in the samples including excess SFC. The detection limit of the assay was 1ng/ml: the good linear relationships between peak area and the concentration of SDB were found in even low ranges, 1 to 40ng/ml of human serum. Mean recovery and reproducibility (n=5) of the method were 102.0% and RSD(%)=1.4 for 40ng/ml, and 100.9% and RSD(%)=1.8 for 500ng/ml of human serum, respectively. Present method was successfully applied to the analysis of serum after a single intravenous administration of 0.5mg/kg of SDB to female dogs. Terminal half lives of SDB in dog serum was ca. 7.3h.View full abstractDownload PDF (563K) -
Hitoshi KOIZUMI, Mingyu DING, Yoshihito SUZUKI1991 Volume 40 Issue 5 Pages 245-250
Published: May 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSPhenol-type ultraviolet (UV) stabilizers in polyvinyl chloride (PVC) were analyzed byresonance Raman detection HPLC. For selective and sensitive detection, UV stabilizers were derivatized with 4-dimethylaminoazobenzene-4'-sulfonyl chloride (DABSYL chloride). DABSYL derivatives have their absorption maximum at 460nm and show resonance Raman effect when they are irradiated with a 488.0nm line of an Ar ion laser. Analytical procedure for UV stabilizers in PVC products was as follows. UV stabilizers were separated from the PVC sample after dissolving in tetrahydrofuran. The polymer fraction was precipitated by adding methanol. After filtration, the solution was evaporated to dryness under reduced pressure. The residue was redissolved with 5ml of acetonitrile, and then ml of phenyl salicylate (Salol, internal standard) in acetonitrile was added to the solution. The solution was centrifuged to remove residual polymer. After evaporation of solvent, the residue was reacted with DABSYL chloride. A 10μl portion of the reaction mixture was injected to HPLC. DABSYL derivatives of UV stabilizers were separated by using a Shiseido Capcell Pak® C18 column (4.6i.d.×250mm) and acetonitrile/water (70/30) as an eluent at a flow rate of 1.0ml/min. Chromatograms were obtained by monitoring the resonance Raman scattering at 1136cm-1 from the flow cell which was irradiated vertically with a 488.0nm line of Ar ion laser. The calibration curve based on the relative peak height of the UV stabilizer to phenyl salicylate was linear in the concentration range of 0.1 to 1.0mg/ml for Tinuvin P (corresponding to contents of 0.04w/w% to 0.4w/w% in the PVC sample when 0.25g of the samples were taken for the analysis). The content of Tinuvin P in a PVC product determined by this method was 0.234+0.010w/w% (n=5), which was in good agreement with the theoretical value of 0.24w/w%.View full abstractDownload PDF (791K) -
Akira NAGANUMA, Tadao OKUTANI1991 Volume 40 Issue 5 Pages 251-256
Published: May 05, 1991
Released on J-STAGE: January 18, 2010
JOURNAL FREE ACCESSA rapid and simple preconcentration method by selective adsorption using activated carbon as an adsorbent and potassium O-ethyldithiocarbonate (potassium xanthogenate) is described for the determination of trace amounts of thallium in sediments by graphite furnace AAS. The procedure is as follows: to 100cm3 of sample solution containing less than 0.5μg of thallium, 60mg of potassium xanthogenate and 60mg of activated carbon were added. The pH was then adjusted to 8.0-10.0 using dilute ammonia water. The mixture was allowed to stand for approximately 20min, then mixed for 20s in an ultrasonic agitator and then filtered. The activated carbon which adsorbed the thallium complex was separated from the matrixes. The activated carbon on the filter paper was dispersed in 5cm3 of water by mixing using an ultrasonic agitator. After shaking, 10μl of the suspension was directly injected into the graphite furnace. Both palladium and ascorbic acid were used as matrix modifiers for thallium. The proposed method was used to determine the amount of several environmental reference standard materials, river and marine bottom sediments. The results for standard materials were in good agreement with the certified or reference values. This simple method is suitable for the determination of trace amounts of thallium in the sample containing large amounts of Fe, Al, Ca, Ti and the other elements.View full abstractDownload PDF (727K) -
1991 Volume 40 Issue 5 Pages e1
Published: 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSDownload PDF (56K) -
Hisako OGURA1991 Volume 40 Issue 5 Pages T101-T106
Published: May 05, 1991
Released on J-STAGE: January 19, 2010
JOURNAL FREE ACCESSZinc, lead, iron, manganese, chromium, copper and aluminium in various industrial wastewater samples were determined by ICP-AES. The values (y) obtained by the conventional ICP-AES method were found to be less than those (x) obtained by flame AAS, which is specified in Japan as the official method of analysis for metals in industrial wastewater, when the acid-digested sample solutions were aspirated without dilution. The relationship between x and y could be expressed by the following equation:y=0.88x-0.01 (r=0.997, n=120). This discrepancy in the analytical data obtained by the two methods seemed to be caused by physical interference, i.e., the viscosity of the solutions. Thus, the internal standard and multiple dilution methods for ICP-AES were attempted. The values obtained by these methods agreed well with those obtained by flame AAS. The relationship between the analytical values by internal standard ICP-AES (y') and those by flame AAS was shown as follows: y'=1.03x+0.09(r=1.000, n=50). The internal standard ICP-AES is more highly recommended as a simple and widely applicable method for the determination of heavy metals in industrial wastewater than multiple dilution ICP-AES which requires successive dilution of each sample for at least two times until the constant analytical value can be obtained.View full abstractDownload PDF (565K) -
KO YOSHIDA, Shoji MOTOMIZU1991 Volume 40 Issue 5 Pages T107-T112
Published: May 05, 1991
Released on J-STAGE: June 19, 2009
JOURNAL FREE ACCESSSodium and potassium ions were spectrophotometrically determined by a solvent extraction/flow injection method incorporated with a cation exchanger column. The ion association complexes which formed between alkali metal-crown ether complexes and anionic dye were extracted into an organic phase, and the absorbance of the organic phase was measured after the phase separation by a phase separator with poly (tetrafluoroethylene) porous membrane. The manifold was composed of three streams: 1. a carrier stream, 2. an eluent stream, and 3. an extraction solvent stream. The eluent contained 4×10-3M EDTA·3Li. The extraction solvent (1+1 mixture of benzene and chlorobenzene) contained 3×10-3M tetrabromophenolphthalein ethyl ester and 2×10-3M dicyclohexano-18-crown-6. Sodium and potassium ions were separated on a cation exchanger column (2.5mm i.d.×12mm). The eluent was made alkaline (pH 10) by passing through the anion exchanger membrane tubing which was kept in a 0.1M LiOH solution. The absorbance of the organic phase was measured at 615nm. Calibration graphs were linear up to 5×10-4M for Na+ and 8×10-5M for K+, respectively. The sample throughput was 12h-1. The procedure was applicable to river and tap water samples.View full abstractDownload PDF (566K)
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