SX20 Stopped-Flow Spectrometer Options and Accessories
Options and Accessories
A comprehensive range of accessories and upgrades considerably expands the number and type of applications that can be addressed using the SX20. The following are available for both new and existing systems, allowing expansion of the SX20 as research interests evolve.
SQ.1 Sequential mixing
This option provides the SX20 spectrometer with sequential stopped-flow in addition to standard stopped-flow operation. Two reagents ("A" and "B"), are mixed together and allowed to incubate in an ageing loop. After a programmable delay, the contents of the age loop are mixed with a third reagent "C".
PDA.1 Photodiode array
With the PDA.1 accessory, the SX20 can be reconfigured in seconds to provide high performance, rapid scanning capability in absorbance mode. It features up to 1600 UV/Vis spectra per acquisition, wide dynamic range, high sensitivity, logarithmic time-base and rapid sampling frequency. Data can be immediately transferred into Pro-K global analysis package. PDA.1 is available in several versions - including a UV 256-element array with a minimum scan time of 0.65ms and a wavelength range of 200nm to 735nm (only acurate down to 285nm with a standard xenon lamp, see UV.1 below), a visible 256-element array with a minimum scan time of 0.65ms and a wavelength range of 330nm to 1100nm and a high resolution 512-element version.
SEM.1 Scanning Emission Monochromator
Second programmable monochromator to enable automated acquisition of equilibrium and time-resolved fluorescence spectra.
AM.1 Scanning Monochromator (far-UV)
Second programmable monochromator to enable a double-monochromator configuration suitable for far-UV absorbance detection (<250nm).
UV.1 Deuterium light source
The UV.1 is a powerful deuterium light source. The profile of the lamp spectrum is such that the UV output is much enhanced with respect to the visible output; this leads to a reduction in stray light contamination of the far-UV, making this an ideal source for use with the UV version of the PDA.1 photodiode-array detector. With the combination of the UV.1 and the UV PDA.1, accurate, time dependent, spectra between 200nm and 400nm can be obtained.
RC5.1  5µl cell cartridge
The RC5.1 option is a 5µl cell in a removable cartridge. Offers a dead-time of 0.5msecs and optical pathlengths of 5mm and 1mm.
FP.1 Fluorescence polarisation/anisotropy
With the FP.1 accessory, the SX20 can be easily reconfigured to provide high performance fluorescence anisotropy measurements.
DD.1 Dual detection accessory
The dual detection accessory allows the user to simultaneously acquire single and multi-wavelength absorbance and fluorescence data.
DF.1 Dual fluoresence detection accessory
The dual fluoescence detection accessory allows the user to acquire single and multi-wavelength fluorescence data from two channels simultaneously.
AN.1 Anaerobic system
A recently developed system with proven anaerobic performance will ensure that the reaction kinetics of even the most sensitive of samples can be successfully analysed. Ultimate performance is obtained when the AN.1 is used in conjunction with a glove box but excellent results can be achieved even when only rudimentary precautions are taken to exclude air.
QFA.1 Quench-flow adaptor
The quench-flow adaptor allows the SX20 (with option SQ.1) to be configured in minutes to enable quench-flow capability.
Pro-K Global analysis
This is a unique stand-alone software package providing global analysis of time resolved spectral data accompanied by a comprehensive data simulation capability. It features singular value decomposition (a type of factor analysis) allowing spectral component prediction and data reduction. Global fitting to an arbitrary reaction schemes is available through the use of fast numerical integration techniques coupled to a symbolic reaction scheme editor. True intermediate spectra of all coloured species are calculated together with their associated concentration profiles. Multi-wavelength kinetic and PDA data are ideally suited for analysis with Pro-K.
Pro-K II 2nd Order Global analysis
This offers all that its predecessor Pro-K offers but adds second order globalisation to the analysis, whereby separately acquired concentration dependant data sets can be combined for simultaneous analysis. This feature enormously increases the ability to define rates and spectra in more complex models. In addition rapid equilibria can be included in the model facilitating the modelling of pH dependent systems by inclusion of rapid protonation equilibria.
Links to all SX20 Accessories
- SQ.1 Sequential mixing
- PDA.1 Photodiode array
- SEM.1 Scanning Emission Monochromator
- AM.1 Scanning Monochromator (far-UV)
- UV.1 Deuterium light source
- RC5.1 5µl cell cartridge
- FP.1 Fluorescence polarisation/anisotropy
- DD.1 Dual detection accessory
- DF.1 Dual fluorescence detection accessory
- AN.1 Anaerobic system
- QFA.1 Quench-flow adaptor
- Pro-K Global analysis for PC
- Pro-K II 2 nd Order Global analysis for PC
SX20 - the ultimate gold standard in stopped-flow
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