For developing highly sensitive and compact sensors on silicon-on-insulator platforms the sub-wavelength grating (SWG) waveguides are attracting great research interest. With better modal interactions resulting into improved sensitivities, SWGs offer immense potential for chemical sensing applications. This paper reports a subwavelength grating slot waveguide (SWGSW) with improved sensitivity of around 857.14 nm/RIU for label free refractometric detection of industrial chemicals such as glycerine. Furthermore, the effect of optimizing structural parameters on transmission spectra is also analysed.