Peltier thermostatted single cell holders
Three Peltier thermostatted single cell holders are available with a maximum light path length of 10 mm, to enable temperature control using the temperature control program. All feature a temperature setting range of -30 to 130 °C with a measurement probe that can be placed inside or adjacent to cell and a magnetic stirrer to eliminate thermal gradients.
- PTC-517: Single-position Peltier for J-1500 and J-1700 for use with rectanguiar cells up to 10 mm.
- PTC-514: Single-position Peltier for J-1100 for use with rectangular cells up to 10 mm.
- PTC-510: Single-position Peltier for J-1500 and J-1700 for use with rectangular and cylindrical cells up to 10 mm.
Automatic 6-position Peltier cell changers
The MPTC accessories are designed to enable high sample throughput and productivity. The six-position holder for rectangular cells allows automated spectral scans and parallel thermal ramps on up to six samples at a time. Applicable measurement modes include spectral scans, thermal ramping at single or multiple wavelengths, and thermal ramping with spectral scans at preset temperatures.
• Temperature setting range of -30 to 130 °C
• Temperature sensors for each cell
• Magnetic stirrers for each cell to eliminate thermal gradient
The MPTC-513 system is compatible with optional fluorescence modes including total fluorescence, scanning excitation/emission fluorescence (FMO-522) accessory and fluorescence polarization/anisotropy (see the section on fluorescence).
Application
Temperature-wavelength scan
Measuring CD spectra while controlling the temperature of a sample provides important information about conformational changes associated with temperature perturbations and is used in the study of biopolymers. The temperature control program measures the thermal denaturation curve (temperature scan) and CD spectra as a function of temperature, according to user-selected parameters. An optional thermal denaturation analysis program determines transition temperatures and thermodynamic parameters, such as ΔH and ΔS, from temperature scans.
Thermal denaturation of Ribonuclease A from 20 to 90 °C
a) CD spectra as a function of wavelength.
b) CD signals at several wavelengths as a function of temperature.
c) 3D view of CD scans as a function of wavelength and temperature.
Other temperature control accessories
HTC-572 Pressure-resistant high temperature measurement unit
Thermal denaturation measurements at temperatures over 100 °C are made difficult by the boiling point of water. Using the same principle as a pressure cooker, this accessory applies pressure to the sample to raise the boiling point, allowing for higher temperatures. Samples can be heated up to 170 °C by applying up to 1 MPa pressure to the cell chamber.
Capillary Cell Jacket
For thermal ramping of microsamples, this accessory allows only 10 μL to be drawn into the capillary cell, which is inserted in a block that is placed in the Peltier cell holder. Accurate Tm measurement of such small sample volumes was not possible in the past.