Design and construction of a compact end-station at NSRRC for circular-dichroism spectra in the vacuum-ultraviolet region.
A synchrotron-radiation-based circular-dichroism end-station has been implemented at beamline BL04B at the National Synchrotron Radiation Research Center (NSRRC) in Taiwan for biological research. The design and performance of this compact end-station for measuring circular-dichroism spectra in the vacuum-ultraviolet region are described. The linearly polarized light from the beamline is converted to modulated circularly polarized light with a LiF photoelastic modulator to provide a usable wavelength region of 130-330 nm. The light spot at the sample position is 5 mm × 5 mm at a slit width of 300 µm and provides a flux greater than 1 × 10(11) photons s(-1) (0.1% bandwidth)(-1). A vacuum-compatible cell made of two CaF(2) windows has a variable path length from 1.3 µm to 1 mm and a temperature range of 253-363 K. Measured CD spectra of (1S)-(+)-10-camphorsulfonic acid and proteins demonstrated the ability of this system to extend the wavelength down to 172 nm in aqueous solution and 153 nm in hexafluoro-2-propanol.
Liu
Szu Heng
SH
National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan.
Lin
Yi Hung
YH
Huang
Liang Jen
LJ
Luo
Shiang Wen
SW
Tsai
Wan Lin
WL
Chiang
Su Yu
SY
Fung
Hok Sum
HS
D002164:Camphor / Q000031:analogs & derivatives* / Q000737:chemistry; D002942:Circular Dichroism / Q000379:methods*; D003208:Concanavalin A / Q000737:chemistry; D009211:Myoglobin / Q000737:chemistry; D017510:Protein Folding; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012996:Solutions; D017356:Synchrotrons / Q000295:instrumentation*
D009211:Myoglobin; D011506:Proteins; D012996:Solutions; D003208:Concanavalin A; D012710:Serum Albumin, Bovine; D002164:Camphor; C006881:10-camphorsulfonic acid