Consolidated Radio-isotope Facility
The ISO-certified Plymouth University Consolidated Radio-isotope Facility (CORIF) is a dedicated laboratory for the manipulation and analysis of natural and enhanced radioactive materials and applications of radioactivity in material analysis. It offers a wide range of ISO-certified research and consultancy services to external academic, public and private sector clients. Data quality is assured through regular participation in external proficiency tests: e.g. Max Rübner Institute (MRI), Germany; National Physical Laboratory (NPL), UK; International Atomic Energy Agency (IAEA), Austria (data available on request).
The BEACh group has significant expertise in macronutrient (N & P) biogeochemical cycling. This includes a segmented flow analyser (Skalar SAN+ flow analyser, Skalar Analytical B.V., The Netherlands) equipped with a 4 channel chemistry unit (with chemistry manifolds for nitrate/nitrite, ammonia, phosphate, silicate and bromide), a 140 position autosampler ((SA 1050), a 4 channel photometer (6250 Matrix) and a digital interface (Skalar SAN++ 8502) operated in a Windows environment. All critical sample handling and preparation for nutrient analysis is undertaken in dedicated Class 100 laminar flow hoods using clean techniques.
The BEACh group also has several custom designed, automated flow injection (FI) analysers operating under a LABView environment. These are versatile in terms of the chemistries used but are generally configured with spectrophotometric detection for macronutrients (N and P species) and with chemiluminescence detection for micronutrients (e.g. iron species). We also have a sequential injection analyser (SIA; FIAlab 3500 SI system, FIAlab Instruments, Bellevue, WA, USA).
Associated facilities for sample treatment (e.g. size fractionation, digestion) are also available. These include access to an autoclave, a batch photo-oxidation unit incorporating a medium power uv lamp and a low power, flow through photo-oxidation unit for e.g. determining the organic N and P content of water samples. In addition, in house, custom designed, aerobic microcosms are available for studying the dynamics of nutrient uptake and release by bacteria.
A Shimadzu TOC-V instrument is available for the determination of total organic carbon (TOC), non-purgeable dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC). There is a TNM-1 attachment for the simultaneous analysis of total dissolved nitrogen (TDN). The instrument is used for samples ranging from seawater and freshwaters, snowmelt, ground and peat bog waters, and soil leachate
We also have reagentless in situ sensors for real time, high resolution nutrient (N, P, DOC, DON) cycling studies.
The HPLC instrumentation for the analysis of amino acids has been upgraded by the purchase of a Jasco FP2020plus fluorimeter and CHROMNAV v1.18 chromatography data system software.
Trace metal facilities
We have three specially designed trace metal clean laboratories (i) a positive pressure (ISO 9001:2008 accredited) cleanroom (Class 100), (ii) recently refurbished dust free laboratory with three Class 100 work stations, (iii) a dedicated acid bath cleaning laboratory, incorporating a new Milli-Q Reference A+ high purity water system and a Class 100 clean drying bench and (iii) specialist HF facilities for aerosol and sediment digestion.
Within these laboratories we have a suite of analytical instruments for the detection of dissolved trace metals in natural waters (sub nM). Analytical techniques applied include flow injection analysis with spectrophotometric, chemiluminescence and fluorometric detection which are used onboard ship and in the laboratory.
We also have voltammetric instrumentation which are utilised in the laboratory, on-board ship and in-situ to investigate dissolved metal speciation and, in combination with bioassays, the biological impact of metals.
We have recently developed the capability to determine free metal ion concentrations in aqueous samples with salinities ranging from fresh to full sea water. In collaboration with the University of Lleida, we have developed the Absence of Gradients and Nernstian Equilibrium Stripping (AGNES) method to determine free zinc ion at sub nanomolar concentrations. The technique utilises voltammetric instrumentation and has been applied to samples collected within the Tamar Estuary. It offers the advantages of direct determination of free metal ion concentrations, absence of matrix interferences, minimal sample manipulation, good precision and bias and excellent limits of detection (which can be tailored to the concentration of metal present).
Particulate associated metals in environmental samples (soils, sediments, aerosols and biota) are determined using an extensive equipment base which the BEACh group has access to, including a Varian GFAAS, ICP-MS (VG PQ3 and A VG PQ2+) and high resolution ICP-MS (VG Axiom) as well as ICP-AES facilities.
We also have high and low volume aerosol collectors and rainwater samplers located at a dedicated coastal sampling location (Penlee, west of Plymouth) with supportive continuous air quality measurements.