Sample Preparation

Sunday afternoon's plenary lecture at Pittcon 2008 was presented by Dr. Leroy Hood, President of the Institute for Systems Biology in Seattle, Washington. The lecture was preceded by the Pittcon Heritage Award presentation, which was awarded to Hood.

Pittcon 2008 got off to a great start here in New Orleans. The liquid chromatography sessions at the Ernest N. Morial Center were interesting and informative, such as the session entitled "Liquid Chromatography at the Extreme: Ultra-pressure and High Temperature."

Good morning and welcome to this, LCGC's third year of live, daily coverage from The Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy.

High performance liquid chromatography (HPLC) enhances throughput in countless processes, including environmental analysis, dissolution testing, separation of biomolecules, and total drug analysis. To take advantage of the benefits of HPLC technology, samples and solvents must be cleared of particulate contaminants. Doing so protects instrument components and minimizes maintenance costs. This article outlines HPLC technology, explains the importance of sample preparation, and reviews the factors that must be considered when preparing HPLC samples by membrane filtration. The data from experiments to test these factors show that the physicochemical characteristics of membrane filters can affect HPLC results.

Since 1950, Pittcon has served as a platform for recognition of scientists whose pioneering research helped make dramatic advances in their specific disciplines. The Spectroscopy Society of Pittsburgh (SSP), one of the two sponsoring societies that organize Pittcon, first presented its Spectroscopy Award in 1957 and has recognized the work of leading spectroscopists since. The second Pittcon cosponsor, the Society for Analytical Chemists of Pittsburgh (SACP), began recognizing leading analytical chemists with their annual award in 1978. The list of award recipients is a "who's who" of scientists, including Nobel Laureates, whose work advanced scientific discoveries at an amazing pace while laying the groundwork for the development of modern day instrumentation in mass spectrometry (MS), inductively couple plasma (ICP), Fourier-transform (FT)-IR, and hyphenated instrumental techniques.

Selective sample preparation techniques are particularly attractive for the analysis of trace amounts of small molecules in complex matrices. In this month's instalment, columnist Ron Majors covers the field of immunoextraction, a technique that employs immobilized antibodies to selectively capture specific analytes using molecular recognition via antibody–antigen interactions. Recently, the introduction of commercial products for specific high-volume environmental and food safety applications should spur further applications of this technique.

Since 1950, Pittcon has served as a platform for recognition of scientists whose pioneering research helped make dramatic advances in their specific disciplines. The Spectroscopy Society of Pittsburgh (SSP), one of the two sponsoring societies that organize Pittcon, first presented its Spectroscopy Award in 1957 and has recognized the work of leading spectroscopists every year since. The second Pittcon co-sponsor, the Society for Analytical Chemists of Pittsburgh (SACP), began recognizing leading analytical chemists with their annual award in 1978. The list of award recipients is a "who's who" of scientists, including Nobel Laureates, whose work advanced scientific discoveries at an amazing pace while laying the groundwork for the development of modern day instrumentation, including mass spectrometry, ICP, FT-IR, and hyphenated instrumental techniques. This two-part article will provide a historical perspective on the accomplishments of several Pittsburgh Spectroscopy Award and Pittsburgh Analytical Chemistry Award winners, highlighting some of the work recognized in each decade leading up to Pittcon 2008. Part I will chronicle the years 1957 through 1977 while Part II will highlight the years 1978 through Pittcon 2008.

KDP (long-chain dipalmitate exter of kojic acid) was recently introduced to resolve skin pigment issues resulting from age spots.

Assay results from a porphyry copper project were obtained by fire assay prep and an MS technique by ACME Labs in Vancouver, Canada.

In this month?s installment, columnist Ron Majors covers the field of immunoextraction, a technique that employs immobilized antibodies to selectively capture specific analytes using molecular recognition via antibody?antigen interactions. Recently, the introduction of commercial products for specific high-volume environmental and food safety applications has spurred further applications of this technique.

This month's instalment of "Sample Prep Perspectives" describes a new extraction technique called QuEChERS (standing for quick, easy, cheap, effective and safe and is pronounced "catchers") for the sample preparation of pesticides in foods and agricultural samples. The technique uses simple glassware, a minimal amount of organic solvent and various salt/buffer additives to partition analytes into an organic phase for clean up by dispersive solid-phase extraction (d-SPE). The technique provides good recoveries, is reproducible and costs less than other sample preparation approaches. The technique is being adopted by many laboratories worldwide. It has the potential for applications outside of the pesticide in foods area.

Phenomenex, Inc. (Torrance, California), a leader in the chromatography and separation sciences business, has been named to Deloitte's Technology Fast 50 Program for Los Angeles.

Gilson, Inc. (Middleton, Wisconsin), an industry leader in purification systems for high performance liquid chromatography (HPLC), solid phase extraction (SPE), and gel permetation chromatography (GPC) clean-up, now offers direct support and sales in the United States.

Thermo Fisher Scientific Inc., a leader in the separation sciences and chromatography industries, announces the launch of its enhanced partner program. The program is designed to support the expansion of the companies' informatics activity via its partners around the globe, the world class program will utilize business partners to better meet customer needs in multiple industries. Thermo Scientific?s informatics offerings include laboratory information management systems, chromatography data systems, and spectroscopy software.

The determination of the carcinogenic food processing contaminant furan by headspace sampling of foods is challenging because it can easily escape from the sample during preparation. Furan can also be easily formed as a by-product when the sample is heated in the headspace apparatus. This article describes a number of approaches to overcome these difficulties and alternative methods to quantify furan in a variety of matrices.

HPLC 2007 was held in Ghent, Belgium in June. Last month, columnist Ron Majors summarized some the important column developments as well as other Symposium highlights. This month, he winds up coverage with additional highlights in the areas of technology and applications. Among the topics covered are stationary phase preparation and characterization, multi-dimensional and comprehensive LC, temperature studies, detectors and an application overview.

The Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy, an event that features the newest applications and technologies in the chromatography industry, have announced the 2008 Pittsburgh Conference Memorial National College Grants (PCMNCG) Program.

Ronald E. Majors, LCGC North America columnist and Senior Chemist for the Columns and Supplies Division of Agilent Technologies, Inc., has been awarded the 2007 Martin Gold Medal by the Chromatographic Society in the United Kingdom for outstanding contributions to the chromatography field.

Waters Corporation (Milford, Massachusetts) and Lambda Therapeutic Research Ltd (Mumbai, India) recently announced a joint cooperative agreement that provides innovative analytical laboratory equipment designed to enhance research quality service and business solutions for Lambda and its clients.

Demonstrating the increasing mainstream popularity of chromatography and separation science in general, Encyclopedia Brittanica has added ?sample preparation? to its immense catalog of scientific terms.

Strategic Directions International, Inc. (Los Angeles, California), recently released the results of a comprehensive study of the sample prep market in North America.

Researchers at the Massachusetts Institute of Technology (Cambridge, Massachusetts) have developed a new sample preparation technique for proteomics research.

In a recent article published in the Journal of Proteomic Research, a group of researchers reported a new two-dimensional liquid chromatography (2D LC) protocol for the preparation and analysis of rat neuropeptides.

In a recent issue of Nature Nanotechnology, a group of researchers from the Massachusetts Institute of Technology (Cambridge, Massachusetts) have created a microchip system capable of speeding up the separation and sorting of biomolecules such as proteins.

Triclosan is an ubiquitous antibacterial, antimicrobial chemical found in numerous consumer health care products today. This article demonstrates that triclosan can be quantitatively determined in commercial hand soaps using reversed-phase solid-phase disk extraction coupled to quantification using capillary gas chromatography-atomic emission detection while avoiding emulsions.

Flash chromatography was first introduced by W.C. Still in 1978. The following report published in the June 2006 issue of LCGC North America provided a good overview of the technique.

Molecularly imprinted polymers (MIPs) are synthetic polymeric materials that mimic immunosorbents. They are widely used as sorbents for solid-phase extraction (SPE). The most common way to synthesize them is bulk polymerization because of its simplicity and versatility. This produces a hard monolith that has to be ground and sieved to obtain particles in the desired size range. However, the partial loss of the materials as fine dusts; the irregular shape of the particles produced and their wide size distribution, have led to a search for different polymerization methods to offset the drawbacks of the bulk polymerization process.

This month's Technology Forum looks at the topic of Sample Prep and the trends and issues surrounding it. Joining us for this discussion is LCGC columnist Ron Majors of Agilent Technologies, Willam Ciccone of Mircosolv Technology Corporation, and and Yibai Chen of Fox Chase Cancer Research Center.

The laboratory life science and analytical instrument industry is comprised of a large, diverse group of organizations that manufacture and distribute their products worldwide. However, overall industry sales are concentrated among a small set of companies. Approximately 950 firms are included in the industry, but only about 100 companies have sales above $50 million.

The major advantages of preparative supercritical fluid chromatography (SFC) include separation speed; the ability to achieve chiral separations; lower viscosity of the mobile phases, which allows high flow rates with acceptable pressure drops and results in higher productivity; reduction of solvent use of as much as 90% compared with liquid chromatography; and ease of processing collected sample fractions.