UV, Visible, and NIR measurements up to 2500 nm for MCD and specialized applications.
The J-1700 was specifically designed for more demanding near-infrared CD applications. In addition to the enhanced far-UV capabilities, researchers probing the chiral activity of molecules in the NIR spectral region now have the ability to obtain data at wavelengths up to 2500 nm
System description
The InGaAs detector has a wavelength range from 900-2500 nm, while the PMT ranges from 163-960 nm. The automatic detector interchange allows researchers to obtain both far-UV and NIR measurements without having to manually switch detectors. The addition of a grating monochromator to the double-prism monochromator setup provides low stray light and high light intensity, generating CD signals with high S/N performance throughout a large spectral range.
NIR-CD applications vary from conformational and chirality studies of metal coordination complexes to tuning chiral properties of nanomaterials. Additionally, Magnetic Circular Dichroism (MCD) can be used in conjunction with NIR-CD to probe a chromophore’s electronic structure as well as to induce chirality in compounds.
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● Wavelength range 163-2500 nm
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● Low stray light
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● Simultaneous Multi-Probe (SMP): CD, LD, fluorescence, UV-visible, absorbance
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● Integrated Hg lamp for wavelength calibration
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● Three scanning modes: auto, step and continuous
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● Highly efficient nitrogen purge system: low volume monochromator designed using a flow simulator
Product Specialist
Mats Grapne
α-pinene enantiomers (gas phase) showing excellent performance in the Far-UV region.
CD spectra of Human Serum Albumin (Helix rich), Concanavalin A (β-sheet rich) and Trypsin inhibitor (Random rich) in water with excellent signal to noise to 174 nm.
The same α-pinene sample showing similar superior performance in the vacuum-UV region down to 163 nm.
Exceptional Stray-Light Rejection
High Sensitivity and Wide Dynamic Range of PMT Detector
The gain on a PMT detector is much larger than most detectors, and therefore the signal amplification is larger. Under conditions with adequate light intensity, this typically leads to a larger amount of noise and therefore a lower S/N ratio. However, under conditions where there is a small amount of light hitting the detector (i.e. far-UV region), the gain of the PMT allows for good signal amplification at very low noise, increasing the S/N ratio.
Simultaneous Multi-Probe Measurements
Additionally, the lock-in amplifier obtains a signal at a specific resonance frequency while filtering out noise signals at other frequencies, providing spectra with excellent signal-to-noise ratios.
Multi-probe measurement of Lysozyme showing the simultaneous acquisition of CD, Absorbance, Ex Fluorescence and Em Fluorescence during a thermal-ramping experiment.
The only CD instrument designed to explore the structure and stability of biomolecules by providing the maximum signal-to-noise under highly absorbing, low light intensity conditions of the far-UV spectral region.
Unlike some detectors which only provide good signal-to-noise for low absorbing materials, the J-1000 Series circular dichroism spectrophotometers use high dynamic range detectors to obtain high quality spectra of samples with excellent signal-to-noise, especially for highly absorbing materials found in the far-UV.
