The present invention relates to isolated monoclonal antibodies (mAbs) and/or antigen-binding fragments thereof that specifically recognize indoxyl sulfate, a protein-bound uremic toxin, isolated polynucleotide segment encoding the isolated antibodies and/or antigen-binding fragments thereof, and uses of such isolated anti-IS mAbs and/or antigen-binding fragments thereof to create immunoassay methods, device compositions, and pharmaceutical compositions applied in theragnosis of IS-related diseases.
