Influence of Pendant Arms Bearing Ligating Groups on the Structure of Bismuth Porphyrins: Implications for Labeling Immunoglobulins Used in Medical Applications

International audience; The synthesis of two picket bismuth(III) porphyrins is reported, and their crystal structures are compared. The influence of the nature of the pickets, as well as their number, is discussed in terms of stability, kinetics of metalation, structure, and distortion of the porphyrin. Unexpectedly, the resultsindicate that the coordination sphere of bismuth is not affected by different types of distortion nor is the stability of the complex. For both types of complexes, the X-ray crystallography revealed that a single arm is actually in direct interaction with the bismuth cation, thereby allowing furtherfunctionalization on the porphyrin core as the linkage with immunoglo…

Organochromium complexes - labelled aminoglycoside antibiotics derived from kanamycin A and tobramycin. Synthesis, structural characterization and use as metallotracers for immunoassays.

Abstract The synthesis of metallocenic derivatives of aminoglycoside antibiotics, i. e. kanamycin A and tobramycin, is described. The organometallic-labelled compounds have been obtained from the reaction between the polyaminodrugs and organochromium esters of N-hydroxysuccinimide. The reaction proceeded selectively at the 6′-N position, as might be deduced both from the mass and the pH-dependent 13 C-NMR spectra. The procedure could be regarded as generally useful for the metallolabelling of aminoglycoside antibiotics. As an example of application a competitive immunoassay based on the use of these labels is proposed.

Carbonyl metallo immuno assay: a new application for Fourier transform infrared spectroscopy

Abstract We describe here the development of a new, non-isotopic immunological assay termed CMIA (carbonyl metallo immunoassay) that uses metal carbonyl complexes as tracers and Fourier transform infrared spectroscopy (FT-IR) as the detection method. This assay is based on the particular spectral features of these complexes, which show very strong absorption bands in the 1800–2200 cm −1 spectral range where proteins and organic molecules do not absorb. In Section 1 , the optimisation of the quantitative detection of these tracers is detailed. In Section 2 , the implementation of mono-CMIA is described, including the CMIA assays of three antiepileptic drugs (carbamazepine, phenobarbital, phe…

Premier exemple de multi-immunodosage simultané de deux haptènes par la méthode CMIA (carbonyl metallo immunoassay)

Resume Nous avons recemment mis au point un nouvel immunodosage non isotopique, appele carbonyl metallo immunoassay (CMIA) qui utilise comme traceur des complexes organometalliques et comme methode de detection l'infrarouge a transformee de Fourier (IR-TF). Cet immunodosage a deja ete decrit pour un medicament antiepileptique, le phenobarbital et une hormone steroide endogene, le cortisol. Nous decrivons ici l'extension de ce dosage CMIA au cas de deux autres medicaments antiepileptiques, la diphenylhydantoine (DPH) et la carbamazepine (CBZ). Pour ces deux medicaments, nous avons tout d'abord synthetise des immunogenes specifiques qui nous ont permis d'obtenir des anticorps polyclonaux anti…

Production of specific antibodies and development of a non-isotopic immunoassay for carbamazepine by the carbonyl metallo-immunoassay (CMIA) method.

Abstract As part of our ongoing work to extend the range of applications of the non-isotopic carbonyl metalloimmunoassay (CMIA), previously developed in our laboratory, we describe here the first CMIA study of carbamazepine. The CMIA method uses a metal carbonyl complex as a non-isotopic tracer, and in this case we chose to employ the dicobalt hexacarbonyl moiety (Co2(CO)6) attached to an alkyne. Two organometallic tracers, 3 and 7 , were synthesized, differentiated by the nature and length of the spacer arm of the Co2(CO)6 moiety. Two different coupling methods were subsequently used to synthesize the immunogens 1 and 2, the first one used a carbodiimide, while the second, employed dimethy…

Enzyme Affinity Assays Involving a Single-Use Electrochemical Sensor. Applications to the Enzyme Immunoassay of Human Chorionic Gonadotropin Hormone and Nucleic Acid Hybridization of Human Cytomegalovirus DNA

Quantitative analysis of mixtures of metal-carbonyl complexes by Fourier-transform infrared spectroscopy: application to the simultaneous double immunoassay of antiepileptic drugs by the nonisotopic carbonyl metalloimmunoassay method.

Abstract The feasibility of a double immunoassay of haptens by the nonisotopic carbonyl metalloimmunoassay (CMIA) method is demonstrated. Three different pairings of antiepileptic medications from the groups carbamazepine, diphenylhydantoin, and phenobarbital (for each of which a mono-CMIA is already available) were assayed by double CMIA. The assay method employs as tracers metal–carbonyl complexes that give very strong signals in the range of 1850–2200 cm −1 in the infrared spectrum, permitting quantitative analysis by Fourier-transform infrared spectroscopy. The fact that the signals are individually assignable and of comparable intensity permits quantitative analysis of mixtures of two …

Simultaneous homogeneous immunoassay of phenytoin and phenobarbital using a Nafion-loaded carbon paste electrode and two redox cationic labels

Abstract The dual-analyte homogeneous immunoassay of two antiepileptic drugs was carried out simultaneously at physiological pH by square-wave voltammetry at a Nafion-loaded carbon paste electrode. Phenobarbital (PB) and phenytoin (DPH) were labeled by a cobaltocenium salt (Cc+) and a ferroceneammonium salt (N+Fc), respectively, and the corresponding standard redox potentials were −1.05 V and 0.26 V. Detection limits of 0.25 and 0.2 μM were achieved for PB-Cc+ and DPH-N+Fc (S/N = 3) after a 5-minute accumulation step, with linear responses over the 0.25–5 and 0.2–5 μM ranges, respectively. The relative standard deviation was evaluated to be ≥ 11% for 1 μM of each labeled drug. The separate,…