Focus
How to increase precision in HPLC sample injection. Rheodyne's Tech Note 5 shows how you can maximize HPLC precision by using skillful sample injection techniques. The information is drawn from hundreds of closely controlled experiments using different types of sample injectors and different load ing methods. The 6-page summary of results is written to help both the beginner and the experienced chromatographer. The experiments yielded some surprising answers to highly practical questions. One question: How much sample must you waste to fill a sample loop "completely"? (It's more than you are likely to think.) Another question: When you are reading a syringe to judge the amount of sample being loaded, how much sample can you inject without impairing accuracy? (It's less than you may think.) Get the answers to these and other salient questions now.
Send for Tech Note # 5 . Contact Rheodyne, Inc., PO. Box 996, Cotati, California 94928, U.S.A. Phone (707) 664-9050.
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harmoniously into networks until a consensus is reached on a neutral data format, a detailed specification for en coding digital information in scientific instruments. "Varian intends to re lease such a protocol," says Dessy. " T h e y are willing t o share t h a t with the world. Other analytical instrument vendors will have access t o t h a t and might copy it, merely because they could then be competitive in an envi ronment where there was a D E C com puter." T h e importance of t h e neutral d a t a format, Varian's B a u m a n n explains, is t h a t it makes it possible t o present t h e data in a way t h a t is instrument non specific. "Applications programs can then pick up t h a t data and do trans formations on it without having t o worry whether it came from a Varian, a Perkin-Elmer, or a Hewlett-Packard chromatograph. This will be a pub lished format, and we're encouraging other vendors to interface their instru ments a n d software houses t o write applications software on t h e basis of this format." Barnard of Perkin-Elmer also feels t h a t a neutral d a t a format is needed: "Perkin-Elmer is actively engaged in defining standard data formats for an alytical instrumentation. It is, in fact, a complex task." According t o Board, t h e difficulty in defining a neutral d a t a format arises because of t h e wide differences among instrumental techniques. "Obviously," he explains, " t h e d a t a format one chooses for a gas chromatograph is probably quite different from t h e data format one would choose for an atomic absorption spectrometer." Board says t h a t "Hewlett-Packard is interested in seeing analytical industry standards on data format. T h e industry could really use some movement in t h a t di rection." Because it is so difficult for repre sentatives from different companies t o sit down together and discuss stan dardization protocols, Board suggests: "An organization like t h e Scientific Apparatus Makers Association might provide a mechanism for getting man ufacturers together to establish a com mon data storage format and net working protocols." T h e goal of all these efforts is an open system implementation t h a t will enable different companies' products to interact synergistically in t h e labo ratory of t h e future. " I certainly hope we can bring t h a t about," says Board, "because looking at t h e whole thing from t h e analytical chemist's point of view, that's t h e most efficient way of getting analytical chemistry done." Stuart A. Barman
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©Sherwood Medical· 1984
LEADERSHIP IN ACTION CIRCLE 141 ON READER SERVICE CARD
CIRCLE 181 ON READER SERVICE CARD ANALYTICAL CHEMISTRY. V O L . 5 6 . NO. 3,
MARCH 1984 ·
413 A
