A fluidic device comprising: a base structure comprising: (i) a substrate; (ii) at least one bulk acoustic wave resonator structure supported by the substrate, the at least one bulk acoustic wave resonator structure including a piezoelectric material, a top side electrode arranged over a portion of the piezoelectric material, and a bottom side electrode arranged below at least a portion of the piezoelectric material, wherein a portion of the piezoelectric material is arranged between the top side electrode and the bottom side electrode to form an active region; and (iii) functionalization material arranged over at least a portion of the active region of the at least one bulk acoustic wave resonator structure to form at least one functionalized active region; a wall structure arranged over at least a portion of the base structure and defining lateral boundaries of a fluidic passage containing the active region and being configured to receive a fluid comprising multiple constituents; and a cover structure arranged over the wall structure and defining an upper boundary of the fluidic passage; wherein the base structure defines a lower boundary of the fluidic passage; characterised in that one or more of the wall structure, the cover structure, or a portion of the base structure non-coincident with the active region comprises additional functionalization material to form at least one absorber configured to bind at least one analyte; wherein the at least one functionalized active region comprises a first aggregate surface area exposed to the fluidic passage, and the at least one absorber comprises a second aggregate surface area exposed to the fluidic passage that is at least equal to the first aggregate surface area exposed to the fluidic passage; wherein the second aggregate surface area exposed to the fluidic passage is arranged to increase a dynamic measurement range of the fluidic device by reducing the likelihood of saturation of functionalization material of the at least one functionalized active region at a given analyte concentration. a base structure comprising: (i) a substrate; (ii) at least one bulk acoustic wave resonator structure supported by the substrate, the at least one bulk acoustic wave resonator structure including a piezoelectric material, a top side electrode arranged over a portion of the piezoelectric material, and a bottom side electrode arranged below at least a portion of the piezoelectric material, wherein a portion of the piezoelectric material is arranged between the top side electrode and the bottom side electrode to form an active region; and (iii) functionalization material arranged over at least a portion of the active region of the at least one bulk acoustic wave resonator structure to form at least one functionalized active region; a wall structure arranged over at least a portion of the base structure and defining lateral boundaries of a fluidic passage containing the active region and being configured to receive a fluid comprising multiple constituents; and a cover structure arranged over the wall structure and defining an upper boundary of the fluidic passage; wherein the base structure defines a lower boundary of the fluidic passage; characterised in that one or more of the wall structure, the cover structure, or a portion of the base structure non-coincident with the active region comprises additional functionalization material to form at least one absorber configured to bind at least one analyte; wherein the at least one functionalized active region comprises a first aggregate surface area exposed to the fluidic passage, and the at least one absorber comprises a second aggregate surface area exposed to the fluidic passage that is at least equal to the first aggregate surface area exposed to the fluidic passage; wherein the second aggregate surface area exposed to the fluidic passage is arranged to increase a dynamic measurement range of the fluidic device by reducing the likelihood of saturation of functionalization material of the at least one functionalized active region at a given analyte concentration.