微波等离子体炬分子同位素光谱法用于溶液中硼同位素定量分析OA

To meet the demand for rapid analysis of boron isotope ratios in solution systems,this study established a microwave plasma torch molecular isotopic spectrometry(MPT-MIS)method for the quantitative determination of boron isotope ratios in solutions.The method employs a microwave plasma torch(MPT)to excite the emission spectrum of BO2 molecules and combines partial least squares regression(PLSR)to extract boron isotopic abundance from full-spectral shape,enabling rapid measurement of boron isotope ratios.The memory effect of boron was effectively reduced by using a quartz inner tube,and the spectral preprocessing methods as well as the wavelength range were systematically optimized based on leave-one-out cross-validation(LOOCV).Under the optimal preprocessing combination(first derivative+area normalization+25-point smoothing)and the optimal wavelength range(464-589 nm),only two latent variables(LVs)were needed to sufficiently extract the spectral information related to isotope abundance.On the three samples in the validation set,the maximum relative bias of the model-predicted 11B/10B ratio was 2.04%,and the prediction precision was 1%—2%(2σ).Furthermore,it was found experimentally that the BO2 molecular spectral intensity exhibited a good linear relationship with total boron concentration in the range of 5-3000 μg/mL(R²>0.999),indicating the potential of this method for simultaneous determination of total boron concentration.This provides a simple and low-cost new approach for the online simultaneous analysis of boron isotope ratios and total boron concentration in scenarios such as the nuclear industry.