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Equipment
A Finnigan MAT Element2 sector Inductively Coupled Plasma Mass Spectrometer
(ICP-MS) with fast-scanning magnet was installed in September 2000
and has become the main instrument for trace metal analysis in our laboratory.
It has detection limits 10-1000 times superior to the VG PQ2+ (see below)
and enables us to analyze trace elements in a few micrograms of foraminiferal
calcite. It has multiple resolutions from 300-12,000, which allows us
to analyze many of the first row transition metals (i.e., Fe, Zn, Co)
that were previously obscured by polyatomic interferences.
A VG PlasmaQuad Turbo 2+ ICP-MS, installed in October 1990, was
the main instrument for trace element analysis until Fall 2000. This mass
spectrometer achieves sub-ppb detection limits on solutions for up to
2/3rd of the elements on the periodic table with sub-ppt detection limits
for up to 1/3rd of the elements.The ICP-MS has been outfitted with a Cetac
ultrasonic nebulizer to increase detection limits on critical elements
like Cd, a Gilson 200 autosampler for automated sample acquisition, and
a thermo-regulated chiller for optimal stability. This integrated system
is now optimized to acquire simultaneous multi-element data (Cd, Ba, Sr,
Mg, Mn, Ca) on foraminifera samples as small as 25 µg.
An interdisciplinary team of UCSB researchers (Lea, Hacker, Mattinson,
Chadwick (geography) and Warner (Bio)) are trying through NSF's Major
Research Instrumentation to obtain funding for a multi-collector (MC)
sector ICP-MS. An MC-ICP-MS would have the capability to do high precision
(better than 0.1‰) analysis of isotopic ratios in aqueous solutions
as well as laser ablated samples. Isotopics systems of interest are Li,
B, Si, Ca, Sr, Nd, Lu, Hf, Pb, Th, Pa, U.
Sample Preparation and Support Facilities
The ICPMS sample preparation wet lab includes 4 laminar flow benches
for trace metal clean work, a quartz still and a dual teflon sub-boiling
still for preparation of ultrapure acids and reagents, a double deionization
system for the production of ultrapure water (Culligan organic removal
and mixed bed ion exchange followed by a Barnstead 4-bed DI system), 5
Sartorius electronic analytical balances including an ultra-micro balance
for weighing single chambers, three ultrasonic cleaners and a micro-centrifuge
for purification of biogenic carbonates. The lab also maintains calibrated
standards for most metals as well as calibrated rare isotope spikes for
isotope dilution analysis. Micropaleontological equipment includes binocular
microscopes, one inverted microscope (Nikon) and one video camera-printer
system. Culturing equipment includes the inverted microscope, temperature
baths and light assemblies.
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