CD spectral measurement of protein water solution in vacuum UV region by J-1500 CD spectrometer

CD spectroscopy is an essential tool for structural analysis of proteins. CD spectra reflecting the secondary structure of protein are usually observed from UV region below 260 nm to the vacuum ultraviolet region, however, the water itself used as a solvent has strong absorption in the vacuum UV region. In case of light water (H2O), its absorption becomes drastically higher at around 175 nm and even the absorption of heavy water (D2O), at around 170 nm. Therefore, in order to obtain the highly accurate SSE results, the measurement keeping high signal to noise ratio (S/N) down to such wavelength limit for water is required.

Jasco's J-1500 CD spectrometer allows the researchers to carry out the measurement with high S/N ratio in the vacuum UV region, by incorporating the several latest technologies such as digital lock-in detection in electrical system, high-throughput optics and highly effective nitrogen gas purging system based on computational fluid simulation.

In this application note, the CD measurement of protein water solution (light water: H2O) down to the vacuum UV region was performed in order to carry out the SSE, using of the J-1500 CD spectrometer and multivariate SSE program (Model JWMVS-529).