Strategic separations

Laboratory at the Curie Institute (France) and his colleagues are designing strategies to separate large molecules and particles in capillaries. Until...
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analyze 96 samples in the time it takes for a single-capillary instrument to analyze one sample," explained Dovichi. "There are obvious applications in the pharmaceutical industry for screening the large libraries generated by combinatorial chemistry." Dovichi's team has already developed an assay for proteases, which he says could, in principle, be used for large-scale screening of protease inhibitors. A patent has been issued on the device in the United States.

Strategic separations Jean Louis Viovy of the Physical Chemistry Laboratory at the Curie Institute (France) and his colleagues are designing strategies to separate large molecules and particles in capillaries.

PEOPLE

Alan Walsh 1916-1998 Sir Alan Walsh died on August 3. Walsh was known for his contributions to die field of atomic absorption spectroscopy (AAS). Modern flame AA instruments differ very little from his original concept. Atomic absorption, and its more recent allied techniques, have completely changed metal analysis in commerce, in environmental protection, and in clinical and biological situations. Certainly Alan Walsh contributed much to this revolution. Walsh was born in Lancashire, England, in 1916. He graduated from Manchester University with a major in physics and in 1939 started work at the British NonFerrous Metals Association, developing and using emission spectrochemical analytical methods. In 1946, he moved to Australia to join what would soon be called CSIRO (Commonwealth Scientific Industrial and Research Organisation). Walsh formed a spectroscopy group within the chemical physics section of the industrial chemistry division and quickly made substantial contributions to IR instrumentation. The idea for AA spectroscopy came to him one Sunday in March 1952, while working in his garden. It occurred to him that the absorption of light by atoms, al642 A

Until recently, he said, progress in CE was mainly due to its performance in small ion and molecule separations, although intermediate-sized species, such as proteins and nucleic acids up to about one kilobase (kB) have also been tackled successfully. He pointed out that the success of CE in separating medium-sized nucleic acids boils down to the use of neutral polymer additives, which act as a sieve. However, attempts to separate larger species have been hindered by so-called electrohydrodynamic collective motions in the carrying agent due to inhomogeneous ion transport leading to a polarization of the fluid. In other words, fluid mixing leads to spurious peaks and loss of resolution. "The phenomenon could only be avoided [up to now] by reducing field strength, which leads to impractically long separation times" he said.

ready so important for many years to astronomical physicists, should be a useful alternative to the emission of atoms for chemical analysts. By 1955, he published his first paper in this field. The equipment and technology for flame AA were almost identical to that still being manufactured and used today. But Walsh was much more than an insightful inventor. The early work in his lab successfully provided the technology for lamps, not then commercially available, and for flame burners, because none of those then commercially available worked well for AA. He understood clearly the instrumental requirements, although some of the instrument companies first entering the field failed to heed his advice. Walsh received many honors and awards during his career. In 1977, he was made a Knight Bachelor (Sir Alan) by the Queen of England. He was elected a Fellow of the Royal Society (England) and a foreign member of the Royal Swedish Academy of Sciences. He received the medal of the Royal Society, the Talanta Gold Medal, the Hasler Award of the Society for Applied Spectroscopy, and the first CSI Award in Analytical Spectroscopy. Walsh brought to inorganic analysis great enthusiasm, a way of working with analysts and witii licensees of the CSIRO patents that was persuasive and compelling. He was always unpretentious, always full of clever and innovative ideas. It was a real pleasure to be in his company. Atomic spectroscopy has lost a great man. Walter Slavin

Analytical Chemistry News & Features, October 1, 1998

Viovy and his team hope to tackle the problem using the idea that, rather than a simple polymer acting as carrier, the instabilities in the fluid might be greatly reduced by adding a zwitterionic buffer. The carrier ions are then in fast chemical equilibrium with a large excess of neutral species, so polarization is counteracted by the law of mass action, which tends to restore uniform carrier density at the expense of the neutral form. The buffer makes the system more homogeneous and so removes the source of the instabilities. Using the buffer technique, Viovy's group has separated 100-kB nucleic acids. The idea is still quite new, and he admitted that additional efforts are needed to live up to the expectations of the biologists who would like to be able to separate 200-300 kB nucleic acids with CE.

GOVERNMENT AND SOCIETY

Environmental analysis collaborative starts up Environmental analytical chemists and Oiose who use their data are invited to join a collaborative effort to share knowledge. The International Collaboration for Environmental Analytical Education (ICEAE) is a free service sponsored by the Waste Policy Institute (Blacksburg, VA). According to Larry Keitii, vice president and senior corporate fellow in the Institute, ICEAE will include a database of analytical measurements in all types of media. As currently envisioned. ICEAE will promote international and local collaborations list new sources of funding disseminate information on methods and instrumentation collect analytical data demonstrate aoproaches for samrjlini? and ciuantitative analysis organize short courses provide a means for creating collaborative Droposals for grants and con'lid in improvint* environmental curricula and establish a network for sahh-iticals and smdinte-level education For more information or to ioin contact Keith hv fay Pvtftfifi? RW1) or h > mil flarrv U 'it & ' t