Photo of Dr Pascal Salaun

Dr Pascal Salaun

Lecturer Earth, Ocean and Ecological Sciences

    Research

    Research Interest 1

    My domain of expertise is electroanalysis applied to trace metal speciation. I am interested in the development of novel sensors and analytical methods for the detection and speciation of trace elements at levels encountered in the environment (e.g. freshwater, seawater, biological fluids) and/or pharmaceutical solutions. At the heart of these measurement is the vibrated gold microwire electrode (VGME). During the last few years, I have revisited the use of these electrodes. Due in part to their small diameter (5-10 micrometer), very low detection limits are obtained and same electrodes can be used for weeks. In particular, together with PhD students (Kristoff Gibbon-Walsh, Kalle Miran-Uroic, Zaoshun Bi) and Prof. Van den Berg, we developed reliable fabrication and conditioning procedures. This electrode is the best currently available for the electroanalytical detection of metalloids (As, Sb) and metals (Cu, Hg and Mn). Recently, we also developed a new amalgam electrode consisting of an electrodeposited layer of Hg on silver for speciation of low levels of lead (pM levels) in coastal and open ocean waters.
    Few examples of applications of these developments are:

    - On-site detection of arsenic (III)/(V) in groundwater in a contaminated area of West Bengal where arsenic poses a huge health problem;

    - In-situ (i.e directly in the water column) detection of dynamic/reactive levels of copper in Liverpool Bay. The sensor was placed under a buoy and continuously run for 5 weeks;

    - Pseudopolarography of copper which gives a detailed view of the speciation of Cu in seawater; this was the first report of pseudopolarography at a solid electrode;

    - Speciation of antimony in pharmaceutical drug solutions of pentavalent antimonial that are used for the treatment of laeshmaniasis (skin disease that afflicts millions of people). Levels of Sb(III), that are believed to be responsible for toxic effect within patients, were found to be much higher than previously reported;

    - Detection of sulphide in seawater.

    Research Group Membership

    Research Grants

    Impact Acceleration Account - University of Liverpool 2012

    ENGINEERING & PHYSICAL SCIENCES RESEARCH COUNCIL (EPSRC)

    October 2012 - March 2017

    Can gold assist in the global arsenic problem?: Insights from speciation and development of an on-site system

    ENGINEERING & PHYSICAL SCIENCES RESEARCH COUNCIL (EPSRC)

    September 2007 - September 2012

    Gold microwire: a new tool for trace metal speciation in natural waters

    ROYAL SOCIETY (CHARITABLE)

    October 2010 - October 2012

    Sensor stability: A step towards unattended in-situ and on-site monitoring of trace elements in coastal systems

    ROYAL SOCIETY

    December 2012 - November 2013

    Research Collaborations

    Dominik Weiss

    External: Imperial College London

    Appply voltammetric techniques to characterise the removal of arsenic from aqueous solution onto modified iron oxides

    Dr. Matthieu Waeles

    External: Universite de Bretagne Occidentale

    Applications of solid gold wire electrode for sulfide determination and copper speciation near hydrothermal vents.

    Dr. Dario Omanovic

    External: Rudzer Boskovic Institute

    Speciation of trace elements in marine systems; Development of electroanalytical sensors and fully automated system for their speciation; Monitoring of the dynammic (reactive) metal fraction

    TESLA group / Joerg Feldmann

    External: The University of Aberdeen

    Coupling state of the art chromatographic and spectroscopic equipment (Aberdeen) and voltammetry (Liverpool), insights of the mechanism involved in the translocation of arsenic in plants are expected.