Contents of this data set for the paper: "An integrated optical Bragg grating refractometer for volatile organic compound detection" - Experimental notes recorded during sensing experiments are provided as PDF files. There are 10 such experimental details notes PDF files. - The experimental data that was collected and processed to determine the sensing response of the device to each of the different solvents are provided as Excel files. There are 10 such Excel files. - The data used to create each figure in the manuscript and supplementary information are presented as Excel files, which are clearly labelled as to which figure they refer. There are 5 such Excel files. - The data used to create the QSPR model is contained within the Excel files "QSPR model data set for Fig 5". The applicable NMR and IR spectra of the modified polysiloxane utilised in this work are also contained in a PDF file named "NMR and IR spectra". Abbreviations: UNC = Uncovered Bragg grating COV = Polysiloxane covered Bragg grating pm = picometre = 1 x 10^-12 m