A photo-electrochemical method for the detection and/or quantification of at least one biological component involving a. Contacting a complex comprising i. a first binding agent labeled with a type II photosensitizer; ii. a second binding agent linked to a particle; wherein at least one of said first or said second binding agent is capable of binding to said biological component and, if one of said first or second binding agent is not capable of binding to said biological component, said binding agent is capable of binding to said other binding agent; wherein said binding of said first and/or second binding agent to said biological component and/or the binding of said binding agent to other binding agent do not interfere with each other; and wherein said binding of at least one of said binding agents to said biological component and/or of said other binding agent to said other binding agent is specific such that a complex is formed only with said biological component; with an electrode using a force, such as a magnetic or electronic force, or a gravitational force, such as sedimentation or centrifugation; b. illuminating said complex in the presence of a redox reporter; and c. detecting the photocurrent generated by the oxidation of said redox reporter at the surface of said electrode. a. Contacting a complex comprising i. a first binding agent labeled with a type II photosensitizer; ii. a second binding agent linked to a particle; wherein at least one of said first or said second binding agent is capable of binding to said biological component and, if one of said first or second binding agent is not capable of binding to said biological component, said binding agent is capable of binding to said other binding agent; wherein said binding of said first and/or second binding agent to said biological component and/or the binding of said binding agent to other binding agent do not interfere with each other; and wherein said binding of at least one of said binding agents to said biological component and/or of said other binding agent to said other binding agent is specific such that a complex is formed only with said biological component; with an electrode using a force, such as a magnetic or electronic force, or a gravitational force, such as sedimentation or centrifugation; i. a first binding agent labeled with a type II photosensitizer; ii. a second binding agent linked to a particle; wherein at least one of said first or said second binding agent is capable of binding to said biological component and, if one of said first or second binding agent is not capable of binding to said biological component, said binding agent is capable of binding to said other binding agent; wherein said binding of said first and/or second binding agent to said biological component and/or the binding of said binding agent to other binding agent do not interfere with each other; and wherein said binding of at least one of said binding agents to said biological component and/or of said other binding agent to said other binding agent is specific such that a complex is formed only with said biological component; b. illuminating said complex in the presence of a redox reporter; and c. detecting the photocurrent generated by the oxidation of said redox reporter at the surface of said electrode.