Archive for the ‘Miscellaneous’ Category

How Dirty Are You? Part 2…Pipet Bulbs…The Answer

Check out the first How Dirty Are You? blog about Parafilm.

The How Dirty Are You? pipet bulb blog showed some interesting data…mainly that I need to clean my pipet bulbs and periodically replace them. I am happy to report that I have changed my pipet bulb twice since and even do some solvent rinses.

The question I posed in the initial blog was about a high intensity peak found when a latex bulb was rinsed with acetonitrile. The question I asked was what type of common additive was responsible for producing such a high signal…

Was it a Dye, Antioxidant or UV Stabilizer?

Some people indicated that they thought it was a phthalate. This is a very good guess based on the numerous times phthalates appear in blank samples, but in this case the compound was identified as butylated hydroxytoluene (BHT).



BHT is an antioxidant compound that is used in everything from rubber to food, pharmaceuticals…even embalming fluid! This stuff is everywhere.

PHOTO: food 2


BHT lotion 1


latex bulb cgram update


Freedom Industries Has Been Fined By OSHA

Freedom Industries, the company responsible for this January’s large MCHM spill in West Virginia, was fined $11,000 by OSHA. Read more at VICE News.

The OSHA fines only cover violations for endangering employee safety. Environmental fines may still be forthcoming.

Electronic Cigarettes Part I: Solution Analysis – What is in the “e-juice”?

Throughout this summer I have the pleasure of working with our intern, Colton Myers. The soon-to-be chemistry senior at Juniata College joined Restek for some practical laboratory experience. We wanted him to work on something “cool” and “interesting,” so what better project is there than electronic cigarettes?VapingYou do not have to look very hard to find someone “vaping” on an e-cig, so these things are definitely gaining traction. Despite their explosive popularity, we have only been able to scrape up a few published reports. In fact, a fairly exhaustive peer-reviewed literature search only turned up a couple of articles. So… needless to say Colton has now spent the past month working on the analysis of electronic cigarettes. As a starting point, we worked on the analysis of the “e-juice” only (note, this is a teaser for more to come later).

So we developed an analytical method for a quick screening of e-cig solutions. We utilized SOF and our approach was KISS (keep it simple, stupid). The table below contains all the specifics of interest:

E-Juice GC-MS ParametersAs a first pass, we tore open an e-cig; used 10 mL of methylene chloride to extract out the juice; concentrated the extract down to 1 mL; and here is what it looks like when using the above parameters:

E-Juice C-GramNow… the aforementioned approach was a simple, qualitative pass for determining what was in the e-juice. We did not use any surrogate standards; however, this could be easily done in the future. In fact, these results indicated that nicotine was ~35% of the total solution, which is a far cry off from the manufacturer’s claim of 1.8%. This we attributed to our extraction/concentration procedure, but this did not matter to us, because our next approach was to just purchase some e-juice straight up (that’s right, keep up with the lingo) and analyze the raw solution, thereby cutting out any errors associated with extraction/concentration, etc… And here is what we got for a raw (i.e., unprocessed) 1.8% nicotine solution:

E-Juice ResultsSo what does all this mean? Well… our method worked well for the rapid analysis of the major electronic cigarette components and our analyte list matches up “fairly” well with what the manufacturer lists on their website. I say fairly because they do not list ethanol, but we clearly found it; and yes, we ran blanks to ensure this was not a contamination issue (hence, how we found water as a “contaminant”). In addition, according to our results this sample is slightly (yes, not orders of magnitude) off from the manufacturer’s claim of 1.8% nicotine in solution. However, our observation is consistent with what Trehy et al. observed in 2011 (“the nicotine content labeling was not accurate with some manufacturers”). Perhaps this is well within the manufacturer’s tolerances or maybe they do not actually test any of this, because as of now not much of the e-cig business is regulated.

Now… you may be asking “why the thick film volatiles column?”…. well I am glad you asked. Remember my teaser from before? See no one actually drinks, bathes in, or injects (I hope) the e-juice. They “vape” it (i.e., draw the solution over an atomizer and inhale the resulting vapor). So honestly, from my point of view I could really care less about what is in the raw e-cigarette solution. I am more interested in what is found in the vapor. So can you take a guess as to what may be found in later parts of this series? Stay tuned…


Trehy, M.L.; Ye, W.; Hadwiger, M.E.; Moore, T.W.; Allgire, J.F.; Woodruff, J.T.; Ahadi, S.S.; Black, J.C.C; Westenberger, B.J. Analysis of electrongic cigarette cartridges, refill solutions, and smoke for nicotine and nicotine related impurities. J. Lig. Chromatogr. Relat. Tech. 2011, 34, 1442-1458.

Flame Retardants on my Mind and on Your Electronics and Your Furniture and….

I recently returned from the Brominated Flame Retardant Workshop in Indianapolis, Indiana. Going to a conference that covers analytical, occurrence and fate, biological and toxicology really puts what Restek does and the products that we make into perspective. Being able to analyze flame retardants in biotic and abiotic matrices is only the first challenge. The analytical methodology and data is used to monitor the levels in humans and the environment, and that data is then used for toxicology studies. Finally, and hopefully, that data is used to form policy that will in turn protect the environment and human health. The BFR meeting covers each of these important links surrounding flame retardants and I always come home from that conference and think about the work that I do to hopefully help the analytical scientist, and the changes I can potentially make around my home and office to reduce exposure to flame retardants (and other persistent organic pollutants).

I enjoyed many of the presentations at the BFR workshop, but one in particular stood out because it is a real problem, but not one that I normally think about. Where do you send your old electronics? With the rapid pace of new technology there is now a rapid increase of electronics waste. Electronic waste (e-waste) recycling in concept is a good thing. We really don’t want all of that in our landfills and electronics contain many precious metals that can be re-used. However, as Li Li from The College of Environmental Sciences and Engineering, at Peking University presented, the process of recycling the e-waste is, in many cases, rudimentary at best. Much of our waste is being shipped to developing nations that use children for labor. The e-waste is being burned in open areas, often very close to where the working families are living. Burning the electronics and plastic casings that are coated with flame retardants and other chemicals creates a toxic smoke that contains lighter brominated diphenyl ether congeners (PentaBDE), dioxins and furans, mixed brominated and chlorinated dioxins and furans, polycyclic aromatic hydrocarbons and heavy metals (just to name a few).



Much of the e-waste recycling is done in or near residential homes and employs children to help sort and disassemble old electronics.


Toxic smoke containing heavy metals and many organic pollutants from burning electronics waste located in someone’s “backyard”.

SDS (MSDS) for VICI® Mat/Sen® Gas-Specific Purifier Modules

Once in a while we (tech service) get asked for a SDS (MSDS) for VICI® Mat/Sen® Gas-Specific Purifier Modules.  Even though we are not required to provide one with the product, sometimes customers need to know their contents.  Simply click on the links below of the appropriate purifier to obtain your SDS (MSDS).


For the Helium, Hydrogen, and Nitrogen Purifier Module  Helium, Hydrogen, and Nitrogen Purifiers

For the Air Module   Air Purifier


Here are a few other related links (if interested).

Contents inside your baseplate trap

Changes are coming to the MSDS; um, I mean the SDS


How Dirty Are You? Part 2…Pipet Bulbs…The Question

Check out the first How Dirty Are You? blog about Parafilm®.

This How Dirty Are You? blog is all about pipet bulbs. Our lab has 14 people and we have at least a few types of pipet bulbs for both borosilicate glass Pasteur pipets or volumetric pipets. I am sure this isn’t surprising to most of you but each person has their favorite type. Our facility only stocks one kind of pipet bulb so we have to order the other types that we like and this makes for some interesting negotiations. Right now, my colleague, Linx is my supplier for my favorite type of pipet bulb…which is the larger light blue one. Preferences for specific bulbs are strong and we have had many conversations about why we like a particular type. For example, Michelle Misselwitz likes the small black bulb because it helps her prevent pulling liquid into the bulb itself.pipet_choices


One of the goals of the original “How Dirty Are You?”’ project was to find contamination sources that are sometimes overlooked so we tested a few bulbs to see what was lurking inside. I tested the bulb that I had been using for some time, my lab mate Jason Thomas’s bulb and a general latex lab bulb with unknown history on how or if it had been used.

What we did

The inside walls and bottom of the bulb was rinsed continually with 400µL of acetonitrile for about 1 minute. Then one microliter of this was tested by GC-MS using generic testing parameters.

The results

Jason’s bulb looked just like the solvent blank! Very clean…My bulb was a different story. As you can see (blue trace), my bulb was filthy. I know some of this might be the different bulb material but Jason also told me that he periodically cleans his bulb with solvent. I think it is safe to say that this was not a practice I had been doing. The latex bulb (yellow trace) was not nearly as dirty as mine but there were some significant peaks.

julie and latex bulbs


I promptly retired that pipet bulb and placed it on my office bookshelf…I just couldn’t throw it out after so many months of service…and to this day it still sits there.

I promptly retired that pipet bulb and placed it on my office bookshelf…I just couldn’t throw it out after so many months of service…and to this day it still sits there.


I think what surprised me the most was the intensity of some of the peaks. Much of my work deals with trace level analysis, ppb level, so I was not accustomed to seeing such high levels. This figure below shows an overlay of chromatograms from my bulb (blue), the latex bulb (yellow) and a 5 ppm hydrocarbon standard (black). In many cases, peaks from my bulb are much larger than this 5 ppm level and even the general lab bulb shows a few peaks higher than the 5ppm level.


pipet overlay


Finally…Here is your question:

One thing I learned from this project is that there are compounds that are just about everywhere and this is the case with the largest peak of the general latex bulb…see starred peak below. So the question is…

A common additive for rubber was found in the latex bulbs. What type of compound was this?

  1. Dye
  2. Antioxidant
  3. UV Stabilizer

Post or email me your answer.

Email me with your answers and look for the data in my next blog.


starred latex bulb





Certified Reference Material Explained

Restek offers Certified Reference Material (CRM) for a wide variety of analytical methods. But what makes a reference material certified and are there different certifications available?

Let’s start with a brief overview of ISO accreditation. A company is first registered to standards such as ISO 9001:2008, which indicates they have an approved quality system in place that is actively followed. To earn accreditation to produce and test CRM, an independent ISO recognized accrediting body visits the site of a reference standard manufacturer; inspect the facility, and reviews established quality system implemented by the manufacturer. Accreditation is awarded when the auditor is satisfied strict criteria of Guide 34 and IEC 17025 are met. Also this accreditation is maintained by periodic visits by the accrediting body to ensure competence and impartiality. Restek has taken specific steps to achieve these goals.

Often, we are asked questions such as are these Reference Materials NIST traceable? Or a question of are these reference materials NIST certified? This may sound similar but they are two entirely different questions.

• Restek CRM’s are NIST traceable.
o Visit the FAQ section for details on this answer as well as other useful information on our Reference Standards.

• Restek CRM’s are not NIST certified. Only NIST can certify their Standard Reference Materials (SRM)

Another question on certification: Are your Reference Materials USP certified?

• Restek CRM’s are not USP certified. Only the USP can certify USP Certified Reference Materials.

Indicating Oxygen and Moisture Traps-“Hey, it looks like my trap arrived partially spent”

The Restek Technical Service group occasionally receives questions from customers who receive their Indicating Oxygen Trap, cat. #22010 or 22011, and they are concerned that it arrived partially spent. This is because the material inside is black on both ends with a green colored material in the middle of the trap. The green material is the indicator that will change to gray when exposed to oxygen. The black material on either side of it is not indicating material, it is black both before and after exposure to oxygen. When the green material changes color it will turn gray, not black, and you will still be able to see the difference between the indicating material and the non-indicating material.




Restek also sells Indicating Moisture Traps, cat. #22014 and 22015, with the same design, having the indicating material towards the middle of the trap and non-indicating material on both ends.





In both the Indicating Oxygen Traps and the Indicating Moisture Traps, the non-indicating material, which has a higher capacity than the indicating material, makes up the majority of the trap.


Both the oxygen and moisture traps have brass fittings on each end, which means they should be used with copper tubing, not stainless steel, as explained in note #1 of “I need a fitting, but which one?” It is also important that all cylindrical gas purifiers should be mounted vertically which will assure the gas flows through the material inside the trap. If a trap is mounted horizontally it is possible the adsorbent in the trap will settle, creating a “path of least resistance” above the adsorbent bed.


GC carrier gas purity is very important for the life of your column, as described in the blog posts “How to Increase the Life Time of your GC Columns? Part I: The Carrier Gas” and “How Long Will a GC Column Last?” and using a gas purifier on your gas lines is highly recommended. Restek offers a complete line of products for gas purification for carrier gas as well as for FID fuel gases.


Thanks for reading!

What is the difference between Restek nitrogen generators which use electricity and those which do not?

You may have reviewed our product webpage for Parker Balston® Nitrogen Gas Generators for LC-MS and noticed that is states: Models N2-04, N2-14, N2-22, and N2-35 require no electricity.  So why don’t these models require electricity but models N2-14A, N2-22A, and N2-35A do?

The simple answer is: those which use electricity have an oxygen sensor and audible alarm built into them, and the others don’t.  The oxygen sensor monitors the oxygen content in the nitrogen process stream.  When the oxygen level increases above the set-point, an alarm will sound letting you know that gas output does not meet purity specifications.




Some other things you may not know about the nitrogen generators we sell:


22129 has a built-in air compressor.

*  If you are going to use nitrogen for GC carrier gas, choose an Ultra-High Purity generator like 21653 and 21654.

*  We also sell maintenance kits.

  Maintenance Kits for Parker Balston® Nitrogen Gas Generators for LC-MS

  Annual Maintenance Kits for Parker Balston® Nitrogen Gas Generators




The Future of Science is Bright: USA Science and Engineering Festival

Halls D & E Containing EPA, NASA & Lockheed Martin

Halls D & E Containing EPA, NASA & Chevron

The 3rd biannual USA Science and Engineering Festival was held last week and was expected to bring in over 300,000 people with 3000 activities, 750 vendors to include 50 colleges and universities. Their mission is to re-invigorate the interest of our nation’s youth in science, technology, engineering and math (STEM) by producing and presenting the most compelling, exciting, educational and entertaining science festival in the United States. Mission accomplished! The event follows a year of school programs such as the Extreme STEM (X-STEM) symposium and the EPA’s P3 (People, Prosperity and the Planet) awards presented to college students with the brightest ideas for protecting human health and the environment. I’m not sure who had more fun at this festival, me or my kids. There were top scientists eager to show off the latest technology which ranged from 3D printing, Mars missions, fighter jet simulators, and finding new planets hundreds of light years away to organic solar cells. We spent about 30 minutes speaking with Alvin Drew & John Grunsfeld, two astronauts who have logged many trips to space over the years. Vanderbilt’s students under the direction of Kane Jennings were able to demonstrate improved performance of bio-solar cells made with spinach utilizing the photosystem 1 (PS1) protein to energize electrons. We were overwhelmed with activities and never had a chance to try out half a dozen flight simulators that Lockheed Martin had in their 100 foot square booth. We will see you there in two years (kids or no kids).

3D Printing a Plastic Chain at the MakerBot Booth

3D Printing a Plastic Chain at the MakerBot Booth

Lab Experiment put together by PSU's Michael Zeman, Director of Science Camps.

Lab Experiment put together by PSU’s Michael Zeman, Director of Science Camps.


PS1 converts sunlight into electrical energy with nearly 100 percent efficiency.

PS1 converts sunlight into electrical energy with nearly 100 percent efficiency.