New products

Information published in this department is based on releases from the manufacturers of the products described. The manufacturers' literature accompanying the products should be consulted for complete details concerning dosage and administration, precautions, contraindications, and possible side effects.

used quite normally for weighing. Like all Mettler instruments, a standard feature of the LP16 is a data interface for connecting to a printer thus providing automatic, detailed records. For more extensive data processing the infra-red drying unit can link up to computers as well. Details from Mettler Instruments Ltd, Kingsmead House, Abbey Barn Road, High Wycombe, Buckinghamshire HPll 1QW, UK. Tel.: 0494 450202. Circle No. 31 Reader Enquiry Card HPLC Designed for the routine production quality control laboratory, Beck-man's QC/Iso System is a low-cost, low maintenance workhorse system that is simple to operate without special training, yet is easily automated for unattended operation. This high performance liquid chromatography system provides fast, reliable, reproducible results for quality control chemists particularly in pharmaceutical, food and beverage, brewing, cosmetic and agricultural industries.
The QC/Iso system is pre-plumbed and easily customer-installed. The package is configured so that individual components can be seen and accessed easily, enabling easy maintenance and service. Based on the high resolution gasliquid chromatographic analysis of cell wall fatty acids which provide a characteristic 'fingerprint' ofthe microbial strain, the method utilizes advanced software which searches a library data-base offatty acid profiles to identify the organism at genus, species and sometimes even subspecies level.
At the heart of the HP 5898A Microbial Identification System is the proven HP 5890A chromatograph, an automated unit which separates 92 and quantifies the fatty acids quickly and precisely. Sample preparation is a simple, one-tube process suitable for all microbes, and batch processing of samples is possible. Samples are inserted into the autosampler and logged into the computer, after which the whole analysis and identification process is completely automatic. Sample sequencing and system calibration are initiated by the software. The peaks are named and quantified, the library searched for best and second-best matches, and a full report printed out, all without operator intervention or interpretation.
The library data are supplied with the system, and currently cover a wide range of known aerobic bacteria. Libraries of anaerobic bacteria and of yeasts will be added later this year. In fixed wavelength, results are presented directly in concentration, complete with user-defined units and a wide range of enzyme analysis routines.
With its built-in VDU, the PU 8820 series is particularly easy to operate. The supportive user interface, which offers operational prompts, audiovisual error warnings and two-key parameter selection, provides both fast and confident operation, irrespective of skill level.
Performance has been optimized for routine applications, and features such as master holographic gratings, silica coated optics and a very large, totally sealed sample compartment, combined with resolution to 0"1 nm, guarantee top quality analytical data.
An extensive range of accessories ensures that PU 8820s can be adapted quickly, conveniently and effectively for a variety of applications.
There are two versions in the series.
The PU 8825 includes a built-in recorder and electrostatic printer and is recommended for routine, standalone operation, while the PU 8820 has been developed for users who want to connect their own recorder or have a current or future requirement for computer operation. At Philips Analytical's applications laboratory in Cambridge, the assignment was to assess the trans-isomer content in a cis-and trans-methyl ester mixture. Comparison of the spectra of the two pure compounds as 2% solutions in carbon disulphide showed them to be extremely similar, although the trans-isomer had a strong band at 966 cm-1 whereas the cis-isomer only weakly absorbed in this region.
After the cis-isomer component had been removed by spectral subtraction, the band was used to determine the concentration of trans-methyl ester in a mixture by comparing peak height with a standard. As cis-isomer absorbs in this region it is important that it should all be removed from the mixture in this way before measurement.
Since all cis-methyl ester peaks coincide with those of the trans-isomer, it is not possible for the computer to use any of them to calculate the factor required to reduce the cis-isomer peaks to zero upon subtraction from a spectrum of the mixture. There are four basic standard enclosures in the series: a standard TEFV (totally enclosed fan-ventilated) in the alloy frame, and three in cast-iron frames to Newman's up-graded enslosure standard, known as 'Hi-Seal'. The MM Series Hi-Seal will carry a two-year guarantee. The three 'MM' Hi-Seal categories are: the 'GP' for general purpose duty in wet, dusty or otherwise harsh environments; the similarly protected but also ExN certified spark-proof type for semi-hazardous locations; and the EExd 'flameproof' type for hazardous environments.
Though the standard MM Series TEFV motor enclosure is to IP55-one level better than Newman's main competitors--the terminal box goes one step better again, and gives the added protection of IP65.
Another .standard MM Series feature, usually an optional extra, is 94 The first family of three motor types in Newman's new 'MM Series' electric motor design.
In theforeground is a lightweight, alloy-framed TEFVversion Hamilton has introduced a digitally controlled valve driver and positioning system to be used with HVP, HVX and multiport valves. This product consists of a valve driver assembly (including Valve, synchronous motor and encoder) and a controller unit.
The controller will drive up to four valves; it can also be cascaded to other controllers thereby operating up to 320 valves from one source..The operator can program the IVP to switch any or all of the valves, simultaneously and independently, to any valid position for the valve in any desired sequence. A standard RS 232 interface used with the controller provides field selectable baud rates of 300, 1200, 2400 and 9600. The programmable control of 12 positions satisfies the operation of Hamilton's two-, three-, four-, six and eight-port valves. Port-to-port speed is 1/4 of a second for an eight-port valve.

Applications will include:
Multi-column switching in HPLC. Gradient  Hospital at Sutton-in-Ashfieldui simple, straightforward to set up, and fast. Results can be obtained within 15 min of receiving a sample. The procedure first involves converting haemoglobin to its reduced form.
The magnitude of the zero-order spectral shift of the reduced haemoglobin peak at 430 nm to the carboxyhaemoglobin peak at 418 nm is then determined by second-derivative spectrum analysis, using the PU 8800 high performance scanning ultraviolet/visible spectrophotometer. The spectrum of a compound or mixture of compounds can be mathematically differentiated to produce derivative spectra.
Odd-numbered derivatives are of most use in determining the exact points of absorbance maxima of the original or zero-order spectrum and hence the qualitative properties of the substance under investigation. Even-numbered derivatives are helpful in quantitative determinations.
The latter prove particularly useful when the properties of zero-order spectrum are changed as a result of interferents such as base-line shift, alteration in base-line slope, the presence of other compounds with similar optical properties, or of inert material such as air bubbles, insolubles or colloidal particles. The application of derivative spectroscopy to the measurement of carboxyhaemoglobin is important because current methods are beset by problems. Zero-order spectroscopy is insensitive and confused by the presence of reduced haemoglobin, the Tietz and Fiereck procedure is also insensitive, and diffusion methods are time consuming and unsuitable for routine use. This bench-top, discrete, selective analyser uses the cytochemical differential perfected on Technicon's other haematology systems with two important differencesmthe dwell time is less than min and the differential is an option on each sample. Therefore the analysis of an urgent sample may be performed at any time day or night, selecting complete blood count only or complete blood count plus differential. A total picture will be displayed on the VDU and produced as a hard-copy report on both ticket printer (number only) and screen printer if desired.

Further informationfrom Pye
The system requires a mixed EDTA blood sample from which 100 1 is aspirated. The probe is automatically cleaned and dried between samples using a suction collar. Within the analytical console is stored sufficient reagents to perform 900 samples (3 ml of reagent per sample).
The blood is segmented using a ceramic shear valve prior to mixing with the appropriate reagents. The haemoglobin and white cell peroxidase estimates are performed using white light, whereas red cells, also the laser is able to give greater information on the white cells, producing a neutrophil lobulation index.
The net effect of this advance is a simplification of result production with the print-out reporting in the traditional waymanisocytosis, hypochromia, macrocytosis etc. as absent, +, ++ or +++.
In producing a simple-to-use system, Technicon have also addressed the problem of costs. The capital cost will be competitive with other discrete analysers performing less sophisticated white cell screens. Because of the discrete approach of the H1, reagent usage is limited only to the time ofsample aspiration, thus allowing the smaller laboratory to benefit from cytochemistry without needing the continuous supply of samples which make the H6000 and H6010 cost-effective. Not even the conventional method of systematically varying one parameter at a time can guarantee that the optimum is found.

More information from
The software package CHEOPS offers an intelligent sequential optimization plan. It incorporates the modified and super-modified sequential simplex optimization methods. Several options are also built in (weighted centroid method, normal reflection etc.), allowing the user to tailor the optimization plan to meet his requirements. Optimizations involving variation of up to 10 parameters can be carried out with CHEOPS. As the method used searches for a short pathway to reach the optimum, the number ofexperiments is usually much fewer if compared with the conventional 'one factor at a time approach'.

CHEOPS comprises five programs"
the main driver; an input program; the modified simplex optimization; the super-modified simplex .optimization program. The input program is used to choose and define a simplex method and to specify all the parameters needed in. the optimiza-tion. The output of this program is then used by one of the two simplex programs to start the optimization process. This process can be interrupted by the user at any time and can be resumed without any loss of information.
Further information can be obtained from

Indentifying microbes
The number of organisms needing to be identified in the microbiology laboratory has increased remarkably over the past few years. Newly discovered species such as Legionella pneumophila have assumed a considerable significance, and the range of specific biochemical tests needed to identify bacteria has multiplied. The gas chromatographic procedure at the heart of the new Hewlett-Packard system (The HP 5898A Automatic Microbial Identification System) is not, however, limited to specific groups of bacteria. By separating the cellular fatty acids which are characteristic of the genotype, and automatically searching their profiles against a computer-based reference library, the method can be used to identify any bacterium isolated in pure culture in vitro. The system is limited only by the reference data held on file.
The system combines highresolution gas-liquid chromatographic analysis of cell wall lipids, using the HP 5890A chromatograph, with a computer search against a library of known microbial strains. The process is both safe and simple, with a standard, one-tube sample preparation procedure for all microbes which are first killed, then incubated under fixed conditions. The sample is saponified to release the fatty acids, which are extracted from the aqueous phase before being subjected to chromatographic analysis. The system is calibrated automatically, and the peaks named and quantified. The computer then searches the library for the best and second-best profile matches at genus, species and (where possible) subspecies level, and a hard copy of the analysis and search results is printed out.
The complete HP 5898A system is now available in the UK at around 33000. Hewlett-Packard can also offer a twoor three-year operating lease package, under the terms of which users will be able to rent the system for around 2800 per quarter (plus tax). This would normally come out of the day-to-day operating or revenue budget, and not out of capital funding. In use, the system identifies bacteria at a cost that compares very favourably to that of plastic strip biochemical identification, and at a fraction of the cost of conventional reference methods. Group.
Retailing at 70, it uses digital techniques to give accurate overload monitoring for three phase AC systems. The unit operates from three current transformers connected in star formation to provide approximately 4 A from each phase at full load. The OLR can also be used with the normal metering current transformers.
The unit selects the highest of the input currents, and if this exceeds the full load current setting, the full-load LED glows. When the current is 10% above full load current, the counter in the unit starts counting pulses produced by the internal circuit, whose frequency is proportional to the percentage overload.
The relay will de-energize when the counter is full. The counting system is over-ridden by the intant trip facility, which is also set on the front panel, and is scaled in multiples of full load current. A series of wall charts outlining the principles of mass spectrometry has been produced by Kratos Analytical. Designed as teaching aids, they are available on request to teaching hospitals, university departments and schools. The first covers the mass spectrometer itself and its four component elements. These, explains the chart, consist o fan ion source to generate a beam o f ions from the sample under investigation, an Analyser to separate those ofdifferent mass, a detector to measure the relative abundance of the ions and a vacuum system to provide the appropriate environment. The resulting mass spectrum, it concludes, provides identification of the original sample. Diode array detection makes a large amount of data available to the chromatographer. Spectral and chromatographic data are acquired very rapidlyuduring an analysis up to 8 spectra/s can be saved, over the wavelength range 190-600 nm. The work-station is designed to handle and process this with maximum efficiency.
The good colour graphics, multiple windowing and operating simplicity of the HP 9000 Series 300 computer are put to good effect in the new workstation. During a run, the status of the entire LC system may be displayed on the screen, or the developing chromatogram and changing spectra may be viewed simultaneously.
After a run, chromatograms at any specified wavelength and bandwith may be reconstructed from the spectral data. A spectrum is displayed in the top window of the screen, and by moving a horizontal cursor across the wavelength axis, different chromatograms appear in the lower window. The wavelength offering the best sensitivity and selectivity for the compound is soon determined. Individual peaks may be enlarged for more detailed inspection.
Using a vertical cursor across the time axis, spectral changes over the run can be reviewed. Spectra from different parts of the peak may be frozen on the display, normalized and superimposed, so that individual peaks may be checked for purity. An overlay of the peak at several wavelengths appears in the same display, and any shift in retention time due to an impurity is clearly seen.
ability to convert all spectra from a run into a map. of iso-absorbance data. The conversion is effected in seconds at the touch of a single key, and the cursors may be moved through the map to give a thorough assessment of the sample.
Once the optimum wavelength and bandwidth for each compound has been established, the chromatograms are quantitated simultaneously using integration software. All integration parameters and timed events are defined on the graphics display, and can be modified in seconds so that re-integration may be performed without the need to rerun the sample. The system gives a choice of report formats. Results are stored on Winchester hard disks. An HP 2225 ThinkJet printer may be used for instant hardcopy print-out, while presentation quality copies ofchromatograms and spectra may be produced on the HP 7440 eight-pen colour plotter.
The work-station can be programmed to run its methods in sequence, and to control the various components of the HPLC system, including an autosampler to permit unattended operation. By programming the parameters for separation, detection, evaluation, integration and reporting for each LC method, totally automated analyses may be performed. Hewlett-Packard's new chromatography work-station provides an unprecedented degree of control and data manipulation and extrapolation, and is set to become the new industry standard. The series consists of three instruments: Models 881, 882 and 883, covering the ranges 4000 to 600 cm-1, 400 cm-a and 200 cmrespectively. A monochrome VDU in an adjustable housing provides fast, high resolution graphics allowing fullor part-range infra-red spectra to be viewed and manipulated before being plotted. Spectral data can be copied from one region to another, processed, reformatted and reset at any stage to the original spectrum so that the raw data is never lost. Hard copy output is provided by an ultrafast digital plotter/printer. Plot and print functions permit data to be replotted or results to be printed without having to rerun the spectrum.
An entirely new optical and electronic design concept results in outstanding spectroscopic performance. Ratio recording allows very weakly absorbing samples be measured with a high signal-to-noise ratio. Fast scanning and high sensitivity allow a survey spectrum to be measured and plotted in less than a minute. Fast sampling techniques, such as diffuse reflectance, are well suited to the speed and sensitivity of the 800 Series.