以中红外光透明的单质硫作为薄层色谱的新型固定相。减小固定相颗粒大小有助于分离,因此通过优化实验条件制备了粒径约为500 nm的硫颗粒,并用其制备了普通的薄层板和窄带薄层板以开展原位薄层色谱-红外光谱联用分析。以罗丹明B和龙胆紫以及罗丹明B和溴酚蓝为研究对象,实验结果表明,以单质硫作为新型固定相的薄层板具备一定的分离混合组分的能力,且不影响分离组分的红外检测,可以实现薄层色谱-红外光谱联用分析。
In situ thin-layer chromatography-Fourier transform infrared spectroscopy ( TLC-FTIR ) technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase has strong absorption in FTIR spectrum and brings about severe interference in the detection of samples. This paper proposes to use sulfur fine particles, which is transparent in mid-infrared, as a new type of TLC stationary phase. Additionally, decreasing the particle size of sulfur is very important in TLC-FTIR analysis technique. By optimizing the experimental conditions, the sulfur particle with a size of 500 nm was prepared and the conventional TLC plate and the narrow TLC plate using the sulfur paticles as the stationary phase was prepared. TLC experimental results prove that the TLC plate can separate the mixture of rhodamine B and gentian violet successfully. FTIR analysis confirms that the FTIR spectra of the separated rhodamine B/gentian violet spots and rhodamine B/bromophenol blue spots are in good agreement with the FTIR spectra of pure rhodamine B, gentian violet and bromophenol blue.