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Abstract: A sensitive, simple and time-saving method has been developed for the neutron activation analysis of gallium at concentrations around 10−4 ppm in biological tissues. After a 24-hour irradiation in a thermal neutron flux of 2.8·1013 n·cm−2·s−1 and a purification by ion-exchange chromatography to eliminate troublesome elements such as sodium, iron and copper, the72Ga activity is measured with enough accuracy for the method to be applicable in animal physiology and clinical toxicology.

Abstract: In connection with the study and the treatment of generalised demineralising bone diseases, the amount of phosphorus and calcium has been determined in the hand by “in vivo” neutron activation analysis using252Cf and238Pu−Be isotopic neutron sources. The statistical accuracy of the induced radioactivity measurement carried out on the hand of a normal subject is about 2% for P and Ca, while the standard deviation over a series of 10 analyses performed on a same phantom remains within 3% for both P and Ca. The results are normalized and expressed in grams of P or Ca per cm3 of bone. The values observed on a group of 55 normal subjects and on some osteoporotic patients are given.

Abstract: For the simultaneous determination of many elements in small biological samples, a multi-element analysis has been developed using neutron activation. After a 24-hr irradiation in a neutron flux of 2.5·1014 n·cm−2·sec−1 and after immediate chemical separation without cooling, it was possible to analyse 24 elements in bovine liver (NBS-SRM 1577). The separation apparatus, set up in a shielded cell can work four samples simultaneously, and its operation is fast enough to allow the detection of radioisotopes with a half-life of about 2 hrs (165Dy,57mSr,56Mn). Amounts lower than 10−3 μg of Dy, Eu, Pr, Sm and Yb were determined.

Abstract: The analytical possibilities offered by long-term irradiation of biological samples in a fission neutron flux filtered by a cadmium screen are examined and the preparation of samples for irradiation is described. This specific activation technique is applied to the determination of molybdenum and nickel in the following three reference substances: human serum, NBS bovine liver and BOWEN’s kale.

Résumé: Une méthode rapide de dosage du brome dans le plasma sanguin par analyse par activation neutronique est décrite. En mesurant le brome 82m par spectrométrie X, l'analyse dans des échantillons plasmatiques de 10 μl peut être faite en 10 minutes. En présence de grandes concentrations de sodium et de chlore, telles que celles du plasma normal, la plus petite quantité de brome décelable est d'environ 5 ng. Les erreurs statistiques mises à part, l'erreur expérimentale introduit une marge d'incertitude d'environ ±2%. On compare les avantages de différents détecteurs utilisés.

Systematic investigations into the practical problems of labelling transferrin with68Gain vitroare presented. A chemical purification of the68Ga generator eluate is described and the working conditions whereby several millicuries of68Ga may be bound quantitatively onto a few milligrams of transferin are defined.

Abstract: The possibilities and limits of the multi-elemental determinations in biological samples by neutron activation analysis with and without chemical separation are discussed.