A new time- and energy-saving method for the determination of asymmetric dimethylarginine in human serum is presented. Here, a newly developed eluent was used in the sample cleanup of the solid-phase extraction whose composition makes an evaporation step redundant. After derivatization, asymmetric dimethylarginine was quantified by high-performance liquid chromatography with fluorescent detection. The conditions of the solid-phase extraction lead to a relative recovery of asymmetric dimethylarginine of 101%. A concentration of 25 ng/mL was found as the limit of quantification and the batch was highly linear from 25 to 800 ng/mL with the correlation coefficient R2 = 0,9999. Intra-assay coefficients of variation <2.1% and inter-assay coefficients of variation <3.1% indicate a high precision. Since no evaporation is necessary compared to previously published methods, this newly presented method does not only save time, but also is a cost- and energy-saving alternative for the routine quantification of asymmetric dimethylarginine in serum.