In this work, we report on the integration of Hollow-core Optical Fibers (HOF) and Single Walled Carbon NanoTubes (SWCNTs) in order to obtain new functionalized devices by means of the modification of the photonic bandgap (PBG) characterizing the HOF itself. The samples were obtained by coating and partially filling by SWCNTs the termination of HOFs. The infiltration of SWCNTs inside the HOF holes has been accomplished by means of the Langmuir-Blodgett technique. Far field transmission characterizations have been carried out at 1550nm in order to study the influence of the carbon nanotubes within the HOF holes on the HOF PBG. Finally, in light of the sensing features of the SWCNTs, the realized samples have been employed as opto-chemical sensors for volatile organic compounds (VOCs) detection and their sensing capability has been proved by their exposure to VOCs traces. Experimental results demonstrate the success of the SWCNTs partial filling within the HOF holes, the influence of the deposition parameters on the HOF PBG and sensing performances as well as the sensor capability to perform VOCs detection with a good sensitivity and fast response times.