A method of detecting components of a biomarker complex in a biological sample, said method comprising: (a) contacting said biological sample with a device having an immobilized binding agent on the surface thereof in a pattern that generates an optical diffraction signal so that said biomarker complex in said sample specifically binds to said immobilized binding agent, wherein said biomarker complex comprises a first component, a second component, and a third component; (b) contacting said surface with a first detecting binding agent, wherein said first detecting binding agent specifically binds to said first component of the biomarker complex and not to said second or third component of the biomarker complex; (c) detecting said first component by a change in optical diffraction signal produced by said pattern upon binding of said first detecting binding agent to said first component; (d) contacting said surface with a second detecting binding agent, wherein said second detecting binding agent specifically binds to said second component of said biomarker complex and does not specifically bind to said first or third component; (e) detecting said second component by a change in optical diffraction signal produced by said pattern upon binding of said second detecting binding agent to said second component; (f) contacting said surface with a third detecting binding agent, wherein said third detecting binding agent specifically binds to the third component of said biomarker complex and does not specifically bind to said first or second component; and (g) detecting said third component by a change in optical diffraction signal produced by said pattern upon binding of said third detecting binding agent to said third component. (a) contacting said biological sample with a device having an immobilized binding agent on the surface thereof in a pattern that generates an optical diffraction signal so that said biomarker complex in said sample specifically binds to said immobilized binding agent, wherein said biomarker complex comprises a first component, a second component, and a third component; (b) contacting said surface with a first detecting binding agent, wherein said first detecting binding agent specifically binds to said first component of the biomarker complex and not to said second or third component of the biomarker complex; (c) detecting said first component by a change in optical diffraction signal produced by said pattern upon binding of said first detecting binding agent to said first component; (d) contacting said surface with a second detecting binding agent, wherein said second detecting binding agent specifically binds to said second component of said biomarker complex and does not specifically bind to said first or third component; (e) detecting said second component by a change in optical diffraction signal produced by said pattern upon binding of said second detecting binding agent to said second component; (f) contacting said surface with a third detecting binding agent, wherein said third detecting binding agent specifically binds to the third component of said biomarker complex and does not specifically bind to said first or second component; and (g) detecting said third component by a change in optical diffraction signal produced by said pattern upon binding of said third detecting binding agent to said third component.