Analytical Specialties
The product lines that GFS has developed for the analytical community have been natural extensions of Prof. G. Frederick Smith’s original vision for the company. In addition to content embedded at various points in the alphabetical section of this catalog, the following product lines reflect our commitment to advance Analytical Chemistry on all possible fronts:
AMCO Clear® Standards for Turbidity. The value of these standards lies in their potential utility in almost every type of optical or visual calibration process. These techniques govern instruments that operate on the principles of light scattering, transmittance or absorbance, including turbidimeters, nephelometers, colorimeters, spectrophotometers, and clinical analyzers. These standards complement the In-Spec® line of standards (described elsewhere) that service Spectrophotometry and Biomedical instrumentation needs.
Generated in an ultra-pure aqueous medium, the AMCO Clear® permanent suspensions provide the analyst with several significant benefits:
- Non-toxic character
- Long-term stability
- Ease of use, storage, disposal
- Uniformity of particle size, shape and distribution
- Accuracy to +/- stated value from lot-to-lot
The Product characteristics derive from the novel styrene-divinylbenzene (DVB) co-polymer bead suspension. The mean particle diameter of 0.2 micron and particle size distribution of 0.1-0.3 micron ensures consistent light scattering properties, making it uniquely suitable for calibration checks of less than one NTU (Nephelometric Turbidity Unit). Another advantage over formazin-based standards is the ease of use that results from the ability of the AMCO Clear® standard to remain suspended indefinitely.
AMCO Clear® standards are the most reliable and reproducible primary calibration standards currently approved by the EPA for water testing. They are certified for use in turbidimeters and haze meters by the following regulatory bodies:
- EPA Federal Registry, Vol. 47, #42, March 3, 1982 to present.
- Standard Methods for the Examination of Water & Wastewater, APHA-AWWA-WPOCF, 16th – 20th Editions to present.
- ASTM, D1889-00, D6698-01, D6855-03.
- ASBC – American Society of Brewing Chemists, 1986 to present
- Analytica – EBC, 4th Edition, 1987 to present.
They are preferred by most instrument manufacturers and by the U.S. Government for their intrinsic uniform optical properties. Recent work performed by the Nanotechnologies Group at Agilent Technologies Lab confirmed the ability of the Agilent 7010 instrument to quickly and accurately determine particle sizes and the concentrations of the nano-dispersions that make up the AMCO Clear® products.
The GFS AMCO Clear® standards program will continue to develop new products for use as primary standards for the calibration of:
Turbidimeters – measuring turbidity (in NTU, FNU, FAU units)
Haze meters – measuring haze (EBC units)
Haze meters (ASBC) – measuring haze (FTU units)
Suspended Solids Analyzers – measuring total suspended solids (ppm)
Biomedical Instrumentation – measuring bacterial colony counts/protein/blood composition
Visual Process Monitoring – visually measuring fermentation/distillation
Spectrophotometers – measuring percent absorbed and transmitted light or optical density.
A new edition of the turbidity technical manual – The ABCs of NTUs – has become available in 2009. More information on this resource and the AMCO Clear® technology and products, as well as on various instrument manufacturers, can be found at www.amcoclear.com.
Also check out the alphabetical section of this catalog for product information and listings for the In- Spec® line of spectrophotometric standards.
High Purity Acids, Salts, Solutions.
GFS began manufacturing high purity acids in the 1950s and shortly thereafter refined its production technologies in response to the Apollo space program’s need for ultra-high purity acid grades, including perchloric acid. Our acid distillation technologies also allow us to keep pace with advancing instrument capabilities and to accommodate ever lower detection limits (see www.vanishingzero.org).
Today, GFS produces five distinct grades of high purity acids:
- Reagent ACS (parts per million trace metal impurities).
- ACS Superior™ (batter than part per million criteria)
- Redistilled (parts per billion TMI)
- Environmental (better than parts per billion criteria)
- Double distilled (parts per trillion TMI)
Double Distilled Acids are packaged in pre-soaked Teflon® bottles, which can be returned for bottle credit toward you next acid order. GFS also provides bulk packaging options for process applications requiring specific impurity profiles, such as etchant technologies and chemical machining planarization (CMP).
The ability to generate our own ultrapure acids provided GFS with the foundation for a broader line of high purity products characterized by low TMI profiles [spectroscopic purity – usually tested by Inductively Coupled Plasma (ICP) spectrometry]. These include:
· Ultrapure salts – 99.99% to 99.9999% (4N to 6N via the “nines” notation – see page 11 for purity guidelines), Primary and Certified Standards.
· Ultrapure solutions – volumetric standards, buffers, AA and ICP standards, environmental standards, QC and CLP standards, custom spec solutions.
· Matrix modifiers
· Ionization buffers
· Anion and conductivity standards
Check out our web site at www.gfschemicals.com for more details on this classic GFS product collection of high purity acids, salts and solutions, and analytical reagents.
HPLC and Specialty Solvents
GFS has decades of experience with chemical distillations, both organic and inorganic. Our growing experience with acetylenic and olefinic research intermediates has given us even more insights into the purification of volatile, moisture- and temperature-sensitive materials. The grades of solvent offered in this catalog cover a full range of applications and sensitivities. These include products that are distilled-in-glass or quartz, and HPLC solvents where the emphasis is on High Performance.
Each of our specialty solvents is carefully analyzed and certified to meet our published specifications. The quality of each solvent far exceeds reagent specifications set by the A.C.S. Quality is controlled not only by UV Spectrophotometry, but also by capillary gas chromatography with electron capture and flame ionization detectors.
Ultra Low cut-off, Distilled in Glass solvents – consistently pure solvents for
- HPLC
- Gas Chromatography
- Pesticide Residue Analysis
- Spectrophotometry
Ion Exchange Resins and Other Specialties for Chromatography
A broad spectrum of GFS products is available to serve chemists working in areas of product separation or purification, including preparative and analytical chromatography. Examples of products that can be found in the alphabetical section of this catalog and described in more detail on the web include:
- Quaternary ammonium compounds for Ion-Pair Chromatography
- Tetrabutylammonium hydroxide, 1.0M and 0.4M, aqueous
- Tetrabutylammonium dihydrogen phosphate crystal, 98+%
- Silica gel products
- Spherical Nucleosil® and Nucleodur® products
- Standard irregular silicas
- Specialty silica adsorbents
- Silica desiccant grades
- Alumina, chromatographic and desiccant grades
- Molecular Sieves
- Florisil®
- Dowex® Ion Exchange Resins
- Amberlite® and Amberlyst® Resins
- Drierite® desiccant grades
- Filter Aids, activated carbon, diatomaceous earth
- Silicic acids and silica sand
Bioscience Specialties
The GFS Bio-Refined™ product line continues to meet the growing need in the Life Sciences and biochemical fields for high-purity, well characterized inorganic and organic salts for research and bio-analytical applications. These products are carefully purified and checked to meet specific pH requirements as well as for conformance to optical absorbance and trace metal ion specifications.
GFS also offers several useful Biological Buffers, complementing Goods buffers in their ability to elaborate pH-dependent phenomena frequently observed in biological and physiological studies. Non-complexing tertiary amine buffers feature N-substituents that render the amine sterically inaccessible toward metal ion complexation, an important factor in dealing with Cu(II) interference in protein analysis.
The alphabetical section of this catalog also details the line of Royer® resins and precious metal catalysts which feature a unique, patented polyethylenimine-polymer matrix. The GFS web site, www.gfschemicals.com, provides graphical representation of the effectiveness of the Royer® products in various applications, including:
- Pd catalyzed hydrogenolysis of Cbz-alanine using formic acid
- Separation of adenosine, AMP, ADP and ATP
- Various bio-analytical resolutions
- Profile of reuse of a Royer®-Pd hydrogenation catalyst
Consistent with the mission of “The Professor,” G. Frederick Smith, customer input continues to be essential to the development of our specialty analytical product lines. Please let us know if we can be of service or provide you with information beyond what is available on the GFS web site.
For more information, contact service@gfschemicals.com.
