Ambrogio Mazzucotelli

Determination of organotin compounds in marine mussel samples by using high-performance liquid chromatography–hydride generation inductively coupled plasma atomic emission spectrometry

HPLC–hydride generation-ICP-AES for the determination of organotin compounds is described. A detection limit of 7 ng for tin was obtained and the organotin species were completely separated within 7 min. The system has been used for the determination of organometallic compounds in marine mussel samples. Preliminary results obtained in laboratory experiments are presented.

Determination of trace amounts of metalloprotein species in marine mussel samples by high-performance liquid chromatography with inductively coupled plasma atomic emission spectrometric detection

Samples containing metalloproteins have previously been analysed on Sephadex gel-permeation macrocolumns with fraction collection and subsequent determination of the metal content by electrothermal atomic absorption spectrometry. In this study, high-performance liquid cromatography has been directly coupled to inductively coupled plasma atomic emission spectrometry for trace organometallic studies. The eluates from the gel-permeation columns are directly aspirated into the r.f. plasma torch after fixing the monochromator at a specific wavelength. Before atomic emission spectrometric analysis, the eluates pass through an ultraviolet detector in order to provide reference spectra. Data are presented concerning the evaluation of the zinc, copper and cadmium thionein contents of different tissues from marine mussels. Lamellibranch molluscs are often utilized as biological indicators in monitoring programmes. A comparison of the sulphur and metallic chromatograms shows the relationships between the whole group of sulphur-rich proteins and the metallothioneins.

The speciation of trace amounts of organometallics in marine organisms by gel-permeation high-pressure liquid chromatography with PAR derivatization

A high-pressure liquid chromatograph equipped with an off-column calorimetric reactor was used for the determination of metallorganic compounds such as metallothioneins. The stainless-steel gel-permeation column used was first tested with ultraviolet detection of a standard protein mixture. The metallothioneins were determined by absorbance measurements at 520 nm after an off-column reaction of the metal-containing eluates with a buffered 4-(2-pyridylazo)resorcinol (PAR) solution. The eluates were also tested by flame and electrothermal atomic-absorption spectrometry; a correlation between AAS and ICP results and the peak areas of the calorimetric detection was also made. A zinc-inhibiting reagent was also added to the PAR solution in order to find the calorimetric error due to the presence of other metals such as copper or cadmium.

Analysis of gadolinium polyaminopolycarboxylic complexes by HPLC–ultrasonic nebulizer–ICP-AES hyphenated technique

The coupling of the HPLC and ICP techniques allows the determination of both classes of GdIII complexes, with and without the chromophoric group. The ICP signal enables the determination of the compounds containing Gd, while the UV signal gives information on compounds containing chromophoric groups with or without GdIII ions.In this paper we describe the study of the thermal degradation products obtained on heating (120 °C, 28 h) and aqueous solution of the GdIII complex. Starting from a 0.25 mol l–1 aqueous solution of the gadolinium(III) complex of the 10-{2-[2-hydroxy-1-(hydroxymethyl)ethylamino]-2-oxo-1-[(phenylmethoxy)methyl]ethyl}-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (1), we were able to detect the thermal decomposition products.