doi: 10.1080/00032719108052952pmid: N/A
Abstract This is a scanned image of the original Editorial Board page(s) for this issue.
Nakamura, Noriyuki; Matsunaga, Tadashi
doi: 10.1080/00032719108052954pmid: N/A
Abstract We report the development of a fiber-optic sensor based on the principle of the sandwich binding technique for the fluoroimmunoassay. Anti-mouse immunoglobulin G (IgG) antibody was immobilized on the membrane mounted to the edge of the fiber. The sensor was exposed to the solution containing mouse IgG and then allophycocyanin conjugated anti-mouse IgG antibody was added. The helium-neon (He-Ne) laser provides excitation of the sandwich binding antigen-antibody complex. This results in fluorescence emission at the membrane. Increase in the fluorescence intensity from sensing tip was proportional to the amount of mouse IgG in the sample. A linear relationship was obtained between the fluorescence intensity increase and the mouse IgG concentration in the range 0.3 - 9.0 μg/ml.
Suzuki, Koji; Hayashi, Kazuo; Tohda, Koji; Watanabe, Kazuhiko; Ouchi, Mikio; Hakushi, Tadao; Inoue, Yoshihisa
doi: 10.1080/00032719108052955pmid: N/A
Abstract Six kinds of lipopholic 16-crown-5 derivatives possessing double side-chains were synthesized. The Na+-selectivities were examined with poly(vinyl chloride) (PVC) matrix-membrane electrodes using these crown compounds. It is an effective way for obtaining high Na+-selectivity by introducing a bulky side-chain such as a benzyloxymethyl group into the 16-crown-5. The electrodes based on 16-crown-5 derivatives having both a methyl or ethyl group and a benzyloxymethyl group at the pivot carbon (C-15) (3 or 4, see Figure 1) exhibited excellent Na+-selectivity over K+ (log k Na.x = -2.65 and -2.75 for 3 and 4, respectively).
Yi, Xian Yang; Jiang, Jing; Jing, Bei Wen; Ruan, Ke-He
doi: 10.1080/00032719108052956pmid: N/A
Abstract To overcome the IgA interference in enzyme immunoassay for serum secretory IgA (SIgA), a new specific, simple and more sensitive sandwich enzyme immunoassay, fully free of the serum IgA interference, was developed. SIgA standards or samples were added into the wells of polystyrene plate coated with rabbit IgG antibody to human secretory component. After incubation, the wells were washed and then, horseradish peroxidase-labeled Fab′ fragment of goat IgG antibody to human α-chain was added and incubated. The wells were washed again to remove the unbound labeled antibody, and the enzyme activity specifically bound to the well was assayed using 3,3′, 5,5′ - tetramethylbenzidine and H2O2 as substrate. The enzyme reaction was stopped by addition of 2M H2SO4. The SIgA concentration was determined from the absorbance at 450 nm. The minimun detectable sensitivity was 6ng/ml. The assay system had very good selectivity overcoming the interference of IgA. As the result of high sensitivity, only small amount of sample (2 μ1 for serum) was needed for analysis. In this assay, no cross reactivity was found with purified human IgG, mIgA, IgM or free secretory component (FSC). The recovery of SIgA mixed with human sera or biles was 99.6–108.1%. The coefficients of within-assay and between-assay variation were 5.8–9.3% and 6.2–9.2% respectively. It correlated well with a liquid phase competitive radioimmunoassay for human serum SIgA (r=0.96, n=30, P<0.0l). The level of SIgA in normal human serum was 8.04±3.60 (SD) μg/ml (n=117) and increased significantly in patients with choledocho- lithiasis (57.35±49.70 μg/ml, n=15, P<0.0l). SIgA concentrations in bile samples were also determined by the 2 4′ assay under the condition that FSC did not, interfere with the assay.
Hashida, Seiichi; Tanaka, Koichiro; Yamamoto, Naoko; Uno, Takeshi; Yamaguchi, Ken'Ichi; Ishikawa, Eiji
doi: 10.1080/00032719108052957pmid: N/A
Abstract A novel and sensitive noncompetitive enzyme immunoassay (hetero-two-site enzyme immunoassay) for arginine vasopressin in plasma is described. Plasma (0.3 ml) was diluted 1.3-fold with an appropriate buffer and filtered by centrifugation in a micro-concentrator with polysaccharide membrane to eliminate plasma proteins. Arginine vasopressin in plasma filtrates was biotinylated and trapped onto anti-arginine vasopressin IgG-coated polystyrene balls. After washing the polystyrene balls to eliminate other biotinylated substances, the biotinylated arginine vasopressin was eluted from the polystyrene balls with HCl and was reacted with anti-arginine vasopressin Fab′-peroxidase conjugate. The complex formed was trapped onto streptavidin-coated polystyrene balls. Peroxidase activity bound to the polystyrene balls was assayed by fluorometry. The detection limit of arginine vasopressin was 11 fg (10 amol)/tube. This was 45-fold lower than that by competitive enzyme immunoassay using the same antiserum as used in this study and 9 to 400-fold lower than those previously reported by competitive radioimmunoassays. The assay range of arginine vasopressin in plasma was 0.14–140 ng /l using 100 μl of plasma filtrates corresponding to 75 u1 o f plasma. Plasma levels of arginine vasopressin i n 8 healthy subjects aged 25–41 yr with, ad libitum water in take and normal activity approximately 4 h after breakfast were 0.72 ± 0.22 (SD) ng /l (range, 0.42–1.04 ng /l).
Preti, M. S.; Magrini, O.; Lodi, S.; Melega, C.; Paradisi, R.; Flamigni, C.
doi: 10.1080/00032719108052958pmid: N/A
Abstract A competitive and sensitive enzyme-linked immunoadsorbent assay (ELISA) allowing determination of androstenedione (A) in unextracted human plasma is described. A highly specific antiserum (anti-4-androsten-11α-ol-3,17 dione-11α hemisuccinate-bovine serum albumin) was employed. Horseradish peroxidase (HRP) was used as the label enzyme; free-bound separation was carried out by adsorbing purified IgG of antiserum on polystyrene balls. Plasma protein binding capacity was reduced by adding 8-anilinonaphtalene-1-sulfonic acid ammonium salt (ANSA). After 3h-incubation, enzyme activity was measured by a colorimetric reaction using o-phenylenediamine dihydrochloride as chromogen and hydrogen peroxide as substrate. The sensitivity of the assay was 5 pg/tube. In order to compare ELISA with radioimmunoassay (RIA) A estimations, plasma samples from thirty women with different endocrine disorders were assayed. A good correlation was found between the two techniques: r = 0.930, p. > 0.001. The accuracy, reproducibility and sensitivity of this procedure make it ideal for rapid plasma A determination for clinical studies.
doi: 10.1080/00032719108052959pmid: N/A
Abstract A molecularly imprinted polymer was prepared using tert-butyloxycarbonyl-L-phenylalanine as the print molecule and methacrylic acid as the functional monomer. The bulk polymer obtained was ground, sieved, packed into a column and investigated in the HPLC-mode by frontal chromatography to determine the number of binding sites and dissociation constants for the enantiomers interacting with the polymer. The dissociation constant for the L-enantiomer of the print molecule was lower than for the D-enantiomer (6.3 mM and 8.1 mM, respectively). This means that the affinity for the L-enantiomer was higher than for the D-enantiomer. The number of binding sites in the polymer giving rise to these dissociation constants were determined to be 28 μmol per g dry polymer.
Bermejo, A. M.; López-Rivadulla, M.; Fernández, P.; Cruz, A.
doi: 10.1080/00032719108052960pmid: N/A
Abstract A fast and accurate method for the simultaneous identification and determination of plasma salicylate and paracetamol using Second-Derivate Spectroscopy is described. The method uses a common extraction procedure thus reducing both the quantity of the sample required and the time necessary to carry out the analysis.
Malešev, D.; Radović, Z.; Jelikić-Stankov, M.; Bogavac, M.
doi: 10.1080/00032719108052961pmid: N/A
Abstract By the application of the spectrophotometric methods the composition of the complex and by the pH-metric method the reaction of complex formation, were determined. It was found that a complex MoO3C27H26O16H2 2− was formed. The dissociation constant of rutin was determined pH-metrically at (20.0±0.1)[ddot]C (kd=8.64 × 10−15). The concentration stability constant of the complex was determined by Bent-French and Bjerrum's methods, at various pH-values. Conditions are also given for the spectrophotometric determination of rutin by means of molybdate(II) as well as the accuracy of the method proposed. All Spectrophotometric measurements were done in 70% ethanol, at pH=6.30± 0.05 and ionic strength 0.015, whereas the determination of rutin was carried out in 50% ethanol, at pH=6.40±0.05, at room temperature (20[ddot]C) and the same ionic strength.
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