Disease treatment with advanced biological therapies such as adalimumab (ADM), although largely 16beneficial,is still costly and suffersfrom loss of response. To tackle these aspects, therapeutic drug 17monitoring (TDM) isproposed toimprove treatment dosing and efficacy, but is often associated 18with long sampling-to-result workflows. Here, we presentan in-house constructed ADM-sensor, 19allowing TDM of ADMat the doctor’s office. This biosensor brings fiber optic surface plasmon 20resonance (FO-SPR),combined with self-powered microfluidics,to a point of care (POC)settingfor 21the first time. AfterdevelopingarapidFO-SPR sandwich bioassayfor ADMdetection on a 22commercial FO-SPR device, this bioassay wasimplemented onthefully-integratedADM-sensor. For 23thelatter, wecombined (I) agold coated fiber optic (FO) probe for bioassay implementationand (II) 24an FO-SPR readout system with(III) the self-powered iSIMPLE microfluidic technologyempowering25plasma sample and reagent mixingon the-cartridge as well asconnectiontothe FO-SPR readout 26system. With a calculated limit of detection (LOD)of 0.35 μg/mL in undiluted plasma, and a total 27time-to-result (TTR)within12 min, this innovative biosensor demonstrated acomparable 28performance to existing POC biosensorsfor ADM quantification in patient plasma samples, while29requiringonly 1 μL of plasma. Whereas this study demonstratesgreat potential for FO-SPR 30biosensing at the POCusing ADM as a model case,italso showshugepotential for bedside TDM of 31other drugs(e.g.other immunosuppressants, anti-epileptics and antibiotics), as the bioassay is 32highly amenable to adaptation. ispartof: Biosensors & Bioelectronics vol:206 ispartof: location:England status: Published online