- Email: [email protected]
New dual-syringe solvent delivery system
471
T I B S 14 - N o v e m b e r 1989
the earth's balance of oxyger~tconsump-
tion and its regeneration. Despite their central importance and the: attention which they have received, their catalytic cycles are still not properly understood. This arises largely because of the many intermediate compounds which are formed in their fLtll reaction cycles as electrons are exchanged one at a time in the oxygen-water interconversion process. It is studies of these intermediates which is the topic of the book. The book is the proceedings of a Nobel Conference held in Sweden in July, 1987 in honour of Professor Bo Malmstr6m, and is concerned almost exclusively with biophysical studies of cytochrome c oxidase and of the photosynthetic oxygen-evolving enzyme. It is directed at experts in these areas, being composed essentially of full research papers given by leading researchers and representing state-of-the-art developments of that time. Both of these enzymes presently receive a great deal of attention worldwide aad almost every conceivable physical probe method is being, or has been, applied. Since
there are only eight papers on each topic, the coverage is far from comprehensive - such a task at this level of detail would be almost impossible. The organizers have chosen instead to restrict the contributions to those which have employed conventional spectroscopic (mostly optical, EPR and MCD studies) and kinetic (stoppedflow and flash-activated) methods to try to generate and probe the structures of the intermediates which are formed in the catalytic cycles. The volume has several features which make it very much more attractive than many of those other conference proceedings which cause library managers with a limited budget to break into a cold sweat. These features cause me to recommend the book strongly to any research workers who are directly involved in work on these enzymes. Firstly, the book is actually a special issue of the Swedish journal C h e m i c a Scripta, a high quality journal which is very professionally produced and edited and which is easily quotable as an accessible reference source. Secondly, the majority of the contribu-
tions are original, detailed research papers on completed pieces of work which have not subsequently been published in essentially the same form elsewhere. This feature has prevented the volume from becoming rapidly out-ofdate. Thirdly, the volume has a coherence caused partly by the restriction of the areas which are covered and partly by introductory articles on the role of metal ions in general (R. J. P. Williams) and on theoretical (S. Larsson) and physical chemical (Cowan and Gray) studies of electron transfer in proteins. This is rounded off by a delightful article by Helmut Beinert on historical aspects of the development of research into cytochrome oxidase and a final frank summary of the conference itself by both Beinert and by the book's editor, Tore V~innghrd. These latter articles left me, after reading the book, feeling as if I'd attended the conference myself! P.R. RICH
Glynn Research Institute, Bodmin, Cornwall PL30 4A U, UK.
Product Review A thermospray LC/MS Interface The Thermospray LC/MS interface from Finnigan MAT enables the
powerful Incos 50 GC/MS benchtop mass spectrometer to be coupled to any liquid chromatograph for on-line mass spectrometric analysis. It extends the capability of the instrument to analyse intractable samples which are either too polar or too thermally labile for GC/MS. The unique ion source is coupled with a powerful microprocessor-based electronics unit, which provides optimum temperature control of the ion source and solvent vaporizer. During gradient-elution chromatography, the temperature of the vapori:,er can be programmed to compensate automatically for changing mobile-phase composition, thereby maintaining optimum thermospray ionization in the mass spectrometer. A flow control unit provides the flexibility to switch from column operation to flow injection m o d e , to allow optimization of thermospray parameters. System proteclion is provided such that if a malfunction occurs, LC flow is automatically diverted from
the mass spectrometer, to waste, there-
by allowing fully unattended operation. Typical full scan sensitivity is in the low nanogram range and in the picogram range for selected ion detection. For further information enter no. 138 on the advertising enquiry form.
cDNA products Amersham International now supplies
a complete range of compatible systems for the rapid generation and analysis of cDNA libraries. For phage or plasmid cloning, hybridization or immunological screening, the range offers complete, convenience systems designed for rapid, reliable, high efficiency cDNA library generation at every stage of the process, includes an RPN extraction kit, a cDNA synthesis system plus cDNA cloning system (kgtl0), cDNA cloning system (~.gtll), cDNA cloning system (plasmid PUEX1), and Superscreen immunoscreening system. For further information enter no. 141 on the advertising enquiry form.
New dual-syringe solvent delivery system The model 140A Dual-Syringe Solvent Delivery System from Applied Biosystems enables both microbore and standard chromatography to be performed with the same pumping system. The
unique dual-syringe design and wide dynamic flow range allows the user to perform binary gradients for a variety of applications in HPLC. Dual 10 ml or 40 ml capacity cylinders are easily interchangeable. The pump will deliver pulse-free flow rates with excellent accuracy and precision in the range of 1-5000 pl min -1. To ensure reproducibility, the pump features automatic compressibility compensation. The system also features an active valve system. It offers the user the ability to programme composition, flow and pressure, and can pump a range of fluids from mercury to carbon dioxide. The model 140A also provides flexible software control of external devices and RS 232C communications. For further information enter no. 140 on the advertising enquiry form.
T I B S 14 - N o v e m b e r 1989
the earth's balance of oxyger~tconsump-
tion and its regeneration. Despite their central importance and the: attention which they have received, their catalytic cycles are still not properly understood. This arises largely because of the many intermediate compounds which are formed in their fLtll reaction cycles as electrons are exchanged one at a time in the oxygen-water interconversion process. It is studies of these intermediates which is the topic of the book. The book is the proceedings of a Nobel Conference held in Sweden in July, 1987 in honour of Professor Bo Malmstr6m, and is concerned almost exclusively with biophysical studies of cytochrome c oxidase and of the photosynthetic oxygen-evolving enzyme. It is directed at experts in these areas, being composed essentially of full research papers given by leading researchers and representing state-of-the-art developments of that time. Both of these enzymes presently receive a great deal of attention worldwide aad almost every conceivable physical probe method is being, or has been, applied. Since
there are only eight papers on each topic, the coverage is far from comprehensive - such a task at this level of detail would be almost impossible. The organizers have chosen instead to restrict the contributions to those which have employed conventional spectroscopic (mostly optical, EPR and MCD studies) and kinetic (stoppedflow and flash-activated) methods to try to generate and probe the structures of the intermediates which are formed in the catalytic cycles. The volume has several features which make it very much more attractive than many of those other conference proceedings which cause library managers with a limited budget to break into a cold sweat. These features cause me to recommend the book strongly to any research workers who are directly involved in work on these enzymes. Firstly, the book is actually a special issue of the Swedish journal C h e m i c a Scripta, a high quality journal which is very professionally produced and edited and which is easily quotable as an accessible reference source. Secondly, the majority of the contribu-
tions are original, detailed research papers on completed pieces of work which have not subsequently been published in essentially the same form elsewhere. This feature has prevented the volume from becoming rapidly out-ofdate. Thirdly, the volume has a coherence caused partly by the restriction of the areas which are covered and partly by introductory articles on the role of metal ions in general (R. J. P. Williams) and on theoretical (S. Larsson) and physical chemical (Cowan and Gray) studies of electron transfer in proteins. This is rounded off by a delightful article by Helmut Beinert on historical aspects of the development of research into cytochrome oxidase and a final frank summary of the conference itself by both Beinert and by the book's editor, Tore V~innghrd. These latter articles left me, after reading the book, feeling as if I'd attended the conference myself! P.R. RICH
Glynn Research Institute, Bodmin, Cornwall PL30 4A U, UK.
Product Review A thermospray LC/MS Interface The Thermospray LC/MS interface from Finnigan MAT enables the
powerful Incos 50 GC/MS benchtop mass spectrometer to be coupled to any liquid chromatograph for on-line mass spectrometric analysis. It extends the capability of the instrument to analyse intractable samples which are either too polar or too thermally labile for GC/MS. The unique ion source is coupled with a powerful microprocessor-based electronics unit, which provides optimum temperature control of the ion source and solvent vaporizer. During gradient-elution chromatography, the temperature of the vapori:,er can be programmed to compensate automatically for changing mobile-phase composition, thereby maintaining optimum thermospray ionization in the mass spectrometer. A flow control unit provides the flexibility to switch from column operation to flow injection m o d e , to allow optimization of thermospray parameters. System proteclion is provided such that if a malfunction occurs, LC flow is automatically diverted from
the mass spectrometer, to waste, there-
by allowing fully unattended operation. Typical full scan sensitivity is in the low nanogram range and in the picogram range for selected ion detection. For further information enter no. 138 on the advertising enquiry form.
cDNA products Amersham International now supplies
a complete range of compatible systems for the rapid generation and analysis of cDNA libraries. For phage or plasmid cloning, hybridization or immunological screening, the range offers complete, convenience systems designed for rapid, reliable, high efficiency cDNA library generation at every stage of the process, includes an RPN extraction kit, a cDNA synthesis system plus cDNA cloning system (kgtl0), cDNA cloning system (~.gtll), cDNA cloning system (plasmid PUEX1), and Superscreen immunoscreening system. For further information enter no. 141 on the advertising enquiry form.
New dual-syringe solvent delivery system The model 140A Dual-Syringe Solvent Delivery System from Applied Biosystems enables both microbore and standard chromatography to be performed with the same pumping system. The
unique dual-syringe design and wide dynamic flow range allows the user to perform binary gradients for a variety of applications in HPLC. Dual 10 ml or 40 ml capacity cylinders are easily interchangeable. The pump will deliver pulse-free flow rates with excellent accuracy and precision in the range of 1-5000 pl min -1. To ensure reproducibility, the pump features automatic compressibility compensation. The system also features an active valve system. It offers the user the ability to programme composition, flow and pressure, and can pump a range of fluids from mercury to carbon dioxide. The model 140A also provides flexible software control of external devices and RS 232C communications. For further information enter no. 140 on the advertising enquiry form.