Updated 10/10/99 Can you identify a couple of famous scientists?
There is a wealth of technical literature available free of charge that is published on the Internet, provided that you know where to look. I use the following sites not only when I am working on a method development project but when I want to update myself on the latest in separation technology.
When you get to one of these sites look for "technical literature" or "library", and search away!!
Did you celebrate 
day? You should have because it is 
Whats New?
I have been working with LC and GC - MS. The system that I work on is a Platform II manufactured by Micromass. This is a wonderful system that is easily switched from LC to GC -MS depending on the need in our laboratory. Lately I have been performing more GC-MS and I hope to have some chromatograms and mass spectra soon.
I also do not ever seem to get to far away from cleaning validation. I really enjoy developing methods and our cleaning validation efforts have provided me with an endless supply of molecules. I will be presenting a poster at EAS that outlines a method that was developed in our laboratory for to determine residual dextromethorphan and diphenydramine. We have also turned our attention to herbal products which contain echinacea extract and ginseng extract.
Nonoxynol-9 was last years EAS poster. The nonoxynol-9 work will be publishe in LC/GC in an upcoming winter (2000) issue. Previously, I presented a poster on the analysis of pharmaceutical equipment for residual levels of benzalkonium chloride. The benzalkonium chloride work was published in BioPharm, January, 2000 issue volume 13 number 1.
HPLC, reversed-phase: Nonporous Silica (NPS) column from Micra Scientific. Flow: 1.0 mL/min, (Water:ACN:H3PO4 60:40:0.1) UV detection: 210 nm, 25 µL injection volume, column temperature 40 degrees C.
HPLC, cation exchange, LC-SCX 250 x 4.6 mm column from Supelco. Flow: 3.0 mL/min (45:55 buffer:ACN), UV detection 210 nm, 50 µL injection volume, column temperature 40 degrees C.
Some thoughts on validation.
Do you order science related supplies (instruments or chemicals)? There are two excellent web sites that I enjoy using http://www.labvelocity.com/ and SciQuest. I do not have commercial ties to either company so surf and enjoy.
HPLC
An HPLC system uses a liquid mobile phase, which is pumped, from a solvent reservoir across a column. Traditionally HPLC columns are cylindrical stainless steel tubes measuring 4.6 mm (3.9 or similar sizes) inner diameter by 150 (250 or 300) mm in length and are packed with a chemically modified solid support (usually silica gel although zirconia solid supports are gaining attention). The chemical that is bound to the silica gel is the stationary phase.
Typical HPLC Column (Stainless Steel)
For more HPLC-MS information check out: 
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In Gas Chromatography (GC), a gas is used as the mobile phase, and a liquid that has been bound to a diamataceaous earth solid support (packed column) or the inner wall of a capillary (open tubular or capillary column). Helium (compressed in cylinders) has become the most often used mobile phase (carrier gas) in GC. It is not the ideal gas to use in most GC separations but helium's properties are suitable for many if not all GC applications, and since helium is nontoxic, and relatively inexpensive it has become the most often used carrier gas in GC. Compressed hydrogen is used in the operation of one of the most common detectors (flame ionization detector or FID). The compressed gas will naturally flow out of the cylinder and into the column without the need for pumps. Because of this GC operation is usually less troublesome than HPLC.
Representation of a Hewlett-Packard 5800 GC system.
Like an HPLC column the stationary phase for a GC system is housed inside of a column. Packed columns are typically 6 feet by 1/4 inch, and are made from stainless steel or glass. These columns are similar to HPLC columns in that they contain a solid support (diamatecius earth) with the stationary phase coated (older technology) or bonded (newer technology, more rugged) to it. Capillary columns or open tubular columns are common in GC analysis. Capillary columns are made from fused silica. Typical capillary columns are 30 or 60 m long, and have inner diameters of 0.53 (megabore), 0.32, 0.2 or 0.1 mm. The stationary phase is directly applied to the inner wall of the capillary column obviating the need for the solid support. Many HPLC methods are run at a constant temperature, and often times at ambient temperature. For this reason column ovens are not universally used in HPLC methods. GC is often times operated at elevated temperatures (80 to 250 degrees centigrade), and it is common to for GC methods to employ a ramped temperature throughout the GC run. Therefore, ovens are an integral part of a GC system as can be seen in the above figure.
Like HPLC systems, a GC sample is injected onto the column. There are several ways to inject a sample onto the GC column:
The sample matrix / analytes of interest will determine which injection style is need for a particular analysis.
Once the sample is injected on the column the analyte(s) interactions with the stationary phase will determine how long it is retained on the column. The carrier gas is constantly moving through the column bringing with it the portion of the analyte(s) that are not interacting with the stationary phase. When the analyte(s) complete the journey through the column the analyte(s) are detected, and measured. The following is a list of commonly used GC detectors:
Below is a chromatogram that was obtained with a 0.53 mm, 60 m DB-1 capillary column with flame ionization detection.
Can you identify the scientists below?
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If you are a chromatographer you may find some interesting information on www.chromtalk.com
I really enjoy working with chromatographic separations. I got my first dose when I was performing VOC analysis on drinking waters. It was exceptionally cool to prepare these incredibly low concentration samples, perform purge and trap, and quantitate the analytes after separation on the GC. From day one I was hooked, and now I can't get enough!!
I spent several years at Bucknell University studying derivatization reactions of polyamines, guanidino compounds and thiols with FMOC and AEOC for subsequent analysis by reversed phase HPLC.
My career as an analytical chemist began in environmental analysis.
I am currently working in the pharmaceutical field. It is a difficult chanllange to remain current in a field as broad, and encompassing as the pharmaceutical field. Organizations such as American Association for Pharmaceutical Scientists (AAPS) are of great value. Through workshops, symposia, and various meetings you can remain in contact with what is going on outside of your discipline, and or company.
LC-MS 
is going to replace the traditional UV and photo-diode array. You can get so much more information from a mass spectrum. As technology increases LC/MS systems become easier to use as a chromatographers tool. Price of LC\MS systems is still prohibitive for routine use, again, as tecnology advances the price for LC/MS systems will drop.
has a very interesting homepage. They publish a lot of scientific journals including the Journal of Chromatography.
Would you like to check out some other science homepages?
Would you like to read an essay about Performance-Based Measurement Systems?
My favorite search engine is YAHOO!!!
If you are interested in chemistry then you really should check out 
There are all sorts of articles from various magazines (C&E News, Chem Tech and many more). I can get stuck their for hours!!!
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For my masters work I analyzed environmental samples for small alkyl thiols. More detail can be found in my abstract. It was very interesting work; although, somewhat malodorous. Perhaps in the future I will be able to work with pre-column derivatization again. FMOC did not work as well for derivatizing the thiols that I worked with because the unreacted FMOC co-eluted with one of the derivatized analytes. AEOC worked better for the thiols that I studied because the unreacted AEOC eluted before any of the AEOC derivatized thiols as can be seen in the chromatograms.
I also used FMOC and AEOC as a pre-column derivatizing reagents to study patients with renal failure for guanidines. Guanidine and its analogues that I studied have several active sites. Unfortunately, most of these active sites seemed to react with FMOC causing complicated chromatograms. Samples from patients would contain proteins and many other species that would react with FMOC causing an even more complicated chromatogram. At this point it was determined not to work any further on this project.
My original project was to analyze FMOC and AEOC derivatized biogenic polyamines by HPLC-MS to determine how many FMOC and AEOC molecules react with a single polyamine molecule. Bucknell had an Extrel triple quad with an extrel particle beam interface. Unfortunately, the unreacted FMOC and AEOC in the derivatized sample would bind to a fused silica transfer line in the particle beam interface. After an injection or two the line would be completely blocked. For obvious reasons this project was dropped. Not all LC-MS instruments use a transfer line in the interface but the system that we had used this interface.
At this point I would like to thank Merck & Co. for providing me with the funding to obtain my masters. I would also like to thank Bucknell University for providing me with an excellent education. I would also like to thank Dr. Hans Veening for his guidance and unending support.
Through my work at Bucknell I was nominated and I accepted membership into Sigma Xi. I am honored to be a part of such a distinguished research society. As a part of my membership I recieve The American Scientist. You can check it out by clicking on the Sigma Xi link above.
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PROFESSIONAL EXPERIENCES
Environemental Analysis
I started my career working for a small environmental laboratory, Seewald Laboratories, in Williamsport PA (1982). This was fortuitous because I had to learn how to do all manner of analytical tests. There were only two chemists and we shared all responsibilities. The following is a list of analysis that I would perform in any given week :
I was involved in the early use of solid phase extraction whiched replaced liquid/liquid extraction as the method of choice for pesticide sample preparation. Using purge and trap to analyze water samples for volatile organic compounds (VOCs) was the begining of my love for the science of chromatographic separations.
Most of our testing methods were from Standard Methods for the Determination of Water and Waste Water. The chromatographic methods came directly from the CFRs.
Working in such a lab you learn what water companies and industries are following the rules and which are not. I would know which municipal authorities produced good water and which did not. I worked closely with the DEP which at that time was the DER. I had a good relationship with them and actually enjoyed working with them. I found them to be a very professional organization.
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Pharmaceutical Analysis
I have been working in my new position with a new company. I am a senior analyst with Warner-Lambert. I am working in a formulations facility in Lititz, PA. I have been working on some very challenging HPLC assays. Hopefully you will be able to see some of the work that I have been doing at the 1998 EAS.
I had been a Laboratory Technician for Merck & Co. I worked for the manufacturing division at a plant in Danville PA. We produced both human and animal products. After I obtained my masters I obtained a day shift job in the Technical Operations Department. We worked on factory improvements and various support projects. This was a very interesting job, and I worked with a good bunch of people. I used a lot of chromatographic separations: GC, HPLC, TLC and column chromatography.
I have presented two posters and one talk at the Eastern Analytical Symposiums, EAS. The first presentation was in 1994 and it dealt compared a GC method for determining % water in a post-fermentation isolation stream.
My second poster was in 1995 and it dealt with the determination of low levels (ppm) of solvents in vessel cleanouts. For environmental chemists ppm levels are huge but in the past 10 ppm levels of solvents in vessel cleanouts considered low. This is changing with new regulations and a TOC analyzer is now being used to determine the amount of carbon in a vessel cleanout. The FDA has a rather complicated manner in determining acceptable limits in cleanouts. It depends on what the vessels next use is. If you are cleaning out a vessel that was previously used methanol and methanol is the next solvent to be used the acceptable level of methanol is higher than if the next solvent is going to be chloroform.
In 1996 I delivered an oral presentation describing a new assay that I developed to separate and quantitate a pharmaceutical intermediate and its trimethyl silane derivative using a porous graphite carbon column.
My sojourn into pharmaceutical testing has brought me into contact with another interesting federal agency THE FDA. I do not envy them their job. There is a vocal group that believes that FDA is preventing them from using cures for their ailments by not allowing certain theraputics. There is an equally vocal group that feels that anything related to medical field must be proven beyond a shadow of a doubt to be safe and effective before it is put on the market. People such as myself are caught in the middle. The federal government should not make decisions for individuals but at the same time we must adhere to Quality standards.
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If you have any comments or questions please feel free to contact me via email at : ![[IMAGE]](emailed.gif){kind=small}
If you are interested in homepages that deal with a more general scientific flavor, you may want to check out the following.
I need to draw chemical structures now and again and I have found two drawing programs that I really like. ISIS draw and ChemWind. They are both free and can be downloded from the above links. When I downloaded ISIS it incorporated itself into my Word program so that to create and insert a drawing all I do is go to [insert] [object] and Isis draw is one of my choices. If I select Isis draw it automatically starts the Isis program and away I go!!
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This Russian botanist founded chromatography. Mikhhail Tswett separated plant pigments on a calcium carbonate column using nonpolar solvents for the mobile phase. He is the father of chromatography!! Drawing is used with permission from McNair and Kazakevich and their book "Basic Liquid Chromatography"
Emanuel Merck (to those of use in the states E. Merck)
In 1816, Emanuel Merck - grandson of the Hessian military councillor Johann Heinrich Merck, a friend of Goethe's - took over the pharmacy. (The roots of Merck KGaA reach back into the 17th century. In 1668, Friedrich Jacob Merck, an apothecary from Schweinfurt, assumed ownership of the "Engel-Apotheke" (Angel Pharmacy) in Darmstadt, which has been in the possession of
the family ever since.)
Thanks to his scientific education, which was extraordinarily good for that time, his efforts in the pharmacy laboratory in isolating and characterizing alkaloids were crowned with success, a
class of highly efficacious vegetable constituents that had been discovered only a short time before. He started with manufacture of these substances "in bulk" in 1827 by offering a "Cabinet of Pharmaceutical and Chemical Innovations" for sale that contained all the alkaloids known at the time.
From these humble beginnings in the pharmacy laboratory, he and his successors gradually built up a chemical-pharmaceutical factory that produced - in addition to raw materials for pharmaceutical
preparations - a multitude of other fine chemicals and from 1990 on also ready-to-use medicines. More than 800 individual products were listed in the catalogue in 1860; by the turn of the century this number had grown to roughly 10,000. From the very start the leading motifs were not only the diversity of the product range, but also the special degree of purity of the preparations.
The photo of Emanuel Merck and the text were provided to me by Dr. Engel Corporate Communications, Merck KGaA, Germany.
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What is it that analytical chemists do (in a general sense)?
An analytical chemist measures things (primarily molecules but some chemists measure subatomic particles and I would not want to leave them out).
It is important to validate a method in order to show that the method is able to accurately determine the concentrations of specific analytes in a specific sample matrix. To this end various statistical measures are important i.e. linearity, method precision, ruggedness to name a few. At times I think that we become so mired in our statistical measures, that we forget the real reason for the analytical method. Sometimes we may scrap a good analytical method because it does not meet a certain statistical function that we set. Prior to setting specific validation criteria, it is important to determine if the criteria in question is appropriate for the method. I would take this a step further, and say that prior to selecting a set of validation experiments that we should weigh the value that will be added to performing the experiment. If the experiment will not provide information which will tell us something important about the method then perhaps the experiment is not worth performing. This is were judgment / disagreements will occur. One man's concept of important analytical information will be another man's waste of time!!!
Keep thinking we will get there (where ever that is!).
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