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Bayesian modelling and quantification of Raman spectroscopy

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Title: Bayesian modelling and quantification of Raman spectroscopy
Authors: Moores, M
Gracie, K
Carson, J
Faulds, K
Graham, D
Girolami, M
Item Type: Working Paper
Abstract: Raman spectroscopy can be used to identify molecules such as DNA by the characteristic scattering of light from a laser. It is sensitive at very low concentrations and can accurately quantify the amount of a given molecule in a sample. The presence of a large, nonuniform background presents a major challenge to analysis of these spectra. To overcome this challenge, we introduce a sequential Monte Carlo (SMC) algorithm to separate each observed spectrum into a series of peaks plus a smoothly-varying baseline, corrupted by additive white noise. The peaks are modelled as Lorentzian, Gaussian, or pseudo-Voigt functions, while the baseline is estimated using a penalised cubic spline. This latent continuous representation accounts for differences in resolution between measurements. The posterior distribution can be incrementally updated as more data becomes available, resulting in a scalable algorithm that is robust to local maxima. By incorporating this representation in a Bayesian hierarchical regression model, we can quantify the relationship between molecular concentration and peak intensity, thereby providing an improved estimate of the limit of detection, which is of major importance to analytical chemistry.
Issue Date: 24-Jan-2018
URI: http://hdl.handle.net/10044/1/72571
Publisher: arXiv
Copyright Statement: © 2018 The Authors.
Keywords: stat.AP
92E99, 65D10, 62F15, 62H12
92E99, 65D10, 62F15, 62H12
Publication Status: Published
Appears in Collections:Mathematics
Faculty of Natural Sciences