A Review of “Application of HPLC-ICP-MS and HPLC-ESI-MS Procedures for Arsenic
Speciation in Seaweeds”
Yu-Jhe Hsieh† and Shiuh-Jen Jiang*,†,§
†Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
§Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University,
Kaohsiung 80708, Taiwan
Brianna Shildt 4/18/2012
The article “Application of HPLC-ICP-MS and HPLC-ESI-MS procedures for arsenic
speciation in seaweeds discussed speciation of arsenics in seaweeds that was done by separation
by ion chromatography and then detected by a inductively coupled mass spectrometry. Arsenic
is understudy because of it toxic properties not only does it depend on the concentration it also
depends on chemical species. It’s important to know the concentration levels in arsenic because
it is found in seafood at high levels and since some countries main part of their diet is seafood
the levels have to be determined for toxicology purposes. Speciation analysis of the seaweed
samples gives researchers the information about toxicity level and which species is more
common in each different type of seaweed. The species of arsenic that was studied was arsenite
(As III), arsenate (AsV), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA),
aresenobetaine (AsB), and arsenocholine (AsC). In order to do the experiments the species have
to be extracted from the seaweed this is done by microwave-assisted digestion. This was
performed on four seaweed samples from a local market. To make sure that the extraction was
efficient the seaweed samples were completely dissoluted to get the total concentrations for
arsenic. Then chromatographic separation was done on all the species using (NH4)2CO3 as the
mobile phase. To detect the arsenic levels the nebulizer on the ICP-MS was connected to the
outlet of the IC column. The results obtained from the IC-ICP-MS showed concentration of As
III had 0.065ug/g, As V had 0.674ug/g, MMA had 0.234ug/g, DMA had 0.200ug/g, AsB had
1.07 ug/g, and AsC was not detected. The samples were also run through ion exchange HPLCESI-MS which showed that all except AsC were detected in several of the seaweed samples that
were analyzed. Finally results showed that the major species of arsenic found in seaweed varies
with each type of seaweed.
This article was average to read because it was hard to follow exactly what was going on.
I felt as though the article jumped around a little bit and it did not go step by step like other
articles that I have read. The article talked about different methods that were done but when
looking at the tables it was hard to figure out which results were from the extracted method and
which were from the dissoluted seaweed samples. From someone who really knew about this it
would be very easy to understand but for someone who only understands the basics behind the
instrument it was difficult to understand. It did provide the information for this experiment to be
repeated. It gave the exact instrument and values to use in order for this experiment to be
repeated. The article did give really good detail on the set up and preforming the experiment so
anyone with a basic background could repeat this. The only downfall was the results section and
discussion they really did not come to a conclusion of what they found and there results were
mixed with the discussion so it became difficult to interpret what the researcher were trying it get
across. A suggestion that I would have is to not put the results with the discussion and to come
to a definite conclusion on what was done. I felt as though it was an open ended experiment and
more research needed to be done. The only other thing that I would say to improve on is to
explain the experiment with the ion exchange HPLC-ESI-MS it was just a little brief and could
have been explained more so someone could repeat it.
Overall this article seemed to be a very interesting topic to read about and it really grab
my attention. The article was just really hard to interpret the results with the discussion. If the
results were separated from the discussion and they came to a definite conclusion it would have
made this article a lot better. The researchers did however explain the experiment very well. It
would be very easy to repeat this experiment since all the reagents, samples, instruments, and
values were listed. This article was a very interesting topic it would have been better if it was
easier to understand.