摘要:

A biosensor was developed using oxidized cytochromeC- sulfite reaction by following the electrochemical reaction between reduced cytochromeCand gold electrode. The change in the current at the fixed potential equal to anodic peak potential of cytochromeCwas proportional to sulfite concentration in the range of 0.4×10−4to 4.0×10−4M.

ISSN:0003-2719    

DOI:10.1080/00032719308017451

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Hyamine 1622 - selective PVC membrane electrodes based on bis (crown ether)s containing the benzo - 18 - crown - 6 moiety were prepared, usingo- nitrophenyloctylether (NPOE) or dipentylphthalate (DPP) as the plasticizer of the PVC membrane. Selectivity coefficients for various interfering ions (inorganic and organic cations), were determined by the mixed solution method. The selectivity of the respective electrodes was found to be affected by the kind of plasticizer employed, and NPOE seemed to be a more suitable plasticizer than DPP. The NPOE electrode system based on the bis (crown ether) that has 11 atoms between the two benzo-18-crown-6 moieties offers the advantage of greater selectivity. The electrodes show excellent electrode properties, and the electrode response was stable in a wide pH range.

ISSN:0003-2719    

DOI:10.1080/00032719308017452

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A potentially implantable glucose biosensor for measuring blood or tissue glucose levels in diabetic patients has been developed. The glucose biosensor is based on an amperometric oxygen electrode and immobilized glucose oxidase enzyme, in which the immobilized enzyme can be replaced (the sensor recharged) without surgical removal of the sensor from the patient. Recharging of the sensor is achieved by injecting fresh immobilized enzyme into the sensor using a septum. A special technique for immobilization of the enzyme on Ultra-Low Temperature Isotropic (ULTI) carbon powder held in a liquid suspension has been developed.

ISSN:0003-2719    

DOI:10.1080/00032719308017453

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The construction and performance characteristics of ion-selective PVC membrane electrode for penbutolol sulfate are described. The electrode, based on ion-pair complex with dinonylnaphthalenesulphonate anion, shows near-Nernstian response in the range 10−3to 5 × 10−6M drug concentration. Its selectivity relative to various cations is reported. Potentimetric methods are used to determine pure drug-substance and active principle in pharmaceutical preparation with good results. It was also applied to the determination of content uniformity and dissolution-rate of film-coated Betapresin® tablets.

ISSN:0003-2719    

DOI:10.1080/00032719308017454

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A method for measuring cellobiase activity of theTrichoderma reeseiCCF 1853 cellulase complex using a Thermal Activity Monitor and a flow - mix mode is described. The kinetic constant KMand the linear dependence of dQmax/dt (the maximum heat flow at the total saturation of enzyme with substrate) on the enzyme concentration were determined. The process of the end product inhibition of cellobiase activity by glucose has been observed too. The obtained results allow to determine the mechanism of the inhibition and an inhibition constant for glucose.

ISSN:0003-2719    

DOI:10.1080/00032719308017455

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Cannabidiol reacts with 2,4-dinitrophenol in alkaline medium to give a red colour having maximum absorbance at 500 nm. The reaction is specific for cannabidiol with 0.1 μg/10 ml as a minimum limit of detection. It also provides the basis for a new spectrophotometric determination of pure cannabidiol and in the presence of other organic compounds. The maximum tolerable limits of these are reported. The method is successfully applied to the determination of cannabidiol from leaves ofCannabis sativagrowing wild and cultivated in Pakistan.

ISSN:0003-2719    

DOI:10.1080/00032719308017456

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Blood serum samples of patients undergoing theophylline therapy were analysed in parallel with a new RP-HPLC method and the therapeutic drug monitoring TDx system. Both techniques are accurate, precise, technically easy, rapid, but the results taken by the TDx method are in all cases higher than HPLC. The mean increase is of about 56%.

ISSN:0003-2719    

DOI:10.1080/00032719308017457

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A sensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) for anti-thyroglobulin IgG in serum is described. Anti-thyroglobulin IgG in serum was reacted simultaneously with 2,4-dinitrophenyl-thyroglobulin and biotinyl-thyroglobulin. The immune complex formed of the three components was trapped onto polystyrene balls coated with (anti-2,4-dinitrophenyl group) IgG and, after washing, reacted with streptavidin-β-D-galactosidase conjugate. After washing, the immune complex was eluted from the polystyrene balls with ϵN-2,4-dinitrophenyl-L-lysine and transferred to polystyrene balls coated with (anti-human IgG γ-chain) IgG. β-D-Galactosidase activity bound to the last polystyrene balls was assayed by fluorometry. Biotinylthyroglobulin and streptavidin-β-D-galactosidase conjugate could be prepared more easily than thyroglobulin-β-D-galactosidase conjugate used in the previous immunoassay. Inactive β-D-galactosidase, used to eliminate interference by anti-β-D-galactosidase antibodies in the previous immunoassay, was not required. The present immunoassay was 300-fold more sensitive than the conventional enzyme immunoassay, although 10-fold less sensitive than the previous immunoassay. Antithyroglobulin IgG was demonstrated in all patients with autoimmune thyroid diseases and 54% of healthy subjects.

ISSN:0003-2719    

DOI:10.1080/00032719308017458

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Two important drugs griseofulvin and dexamethasone have been quantitatively estimated through complexation with fluoranil (tetrafluoro-2,5-cyclohexadiene - 1,4- dione). The optimal experimental conditions, applicability of the suggested method to assay the cited drugs in their tablet forms, and statistical analysis of the results were studied. The results obtained were compared with those of the corresponding official method of assay for each drug, showing good agreement with the official methods. Furthermore, the reaction products have been isolated and subjected to structure elucidation by means of IR-Spectroscopic technique.

ISSN:0003-2719    

DOI:10.1080/00032719308017459

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

An advanced reserved phase High Performance Liquid Chromatographic (HPLC) method using UV detection, at 251, is presented for the simultaneous determination of bamipine combined with tricyclic antidepressants and/or antipsychotics in various pharmaceutical formulations. Sample analyses were performed on a bonded reserved-phase C-2,5 μm, 250 × 4.6 mm ID (Lichrosorb RP-2)column using aqueous ammonium acetate at constant ionic strength 0.015 M and acetonitrile 35: 65 as eluent, at a flow rate of 0.9 ml/min. The pH was adjusted to 4.7 with acetic acid. The presence of acetate buffer both shortens the elution time and improves the symmetry of the chromatographic peaks. The retention time was for bamipine, prochlorperazine, trifluoperazine, thioridazine, chlorprothixene, haloperidol, clomipramine, trimipramine 8.83, 11.83, 11.50, 11.08, 10.42, 8.05, 10.25, 9.67 min respectively. Linearity and precision data have been assessed. The method also involves an investigation of the dependence of the capacity ratio k′ on the pH and the polarity of the mobile phase.

ISSN:0003-2719    

DOI:10.1080/00032719308017460

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor