Method of detecting Symmetrical dimethyl arginine (SDMA) in biological samples. SDMA analogs for generating anti-SDMA antibodies having little or no cross-reactivity with asymmetrical dimethyl arginine, arginine, and monomethylarginine. The analogs have a protected or free thiol (-SH) group or hydroxyl (-OH) group that allow them to be linked to a suitable conjugation target which can be, for example, a protein containing molecule of a label. The anti-SDMA antibodies can be used in diagnostic immunoassay for the diagnosis of SDMA associated disorders and/or diseases.