A new and rapid on-line flow injection (FI) procedure for the preconcentration and separation of aluminum(III) species in dialysis concentrates is described based on the combining of solid phase extraction with Lewatit TP-207 resin and electrothermal atomic absorption spectrometry (ETAAS). Lewatit TP-207 resin being a weakly acidic, macroporous cation exchanger with chelating iminodiacetate groups was firstly used in the determination of Al(III) species. The influences of the analytical parameters such as pH, type of eluent, flow rates of the eluent and sample, volume of the eluent, and matrix ions were investigated. A preconcentration factor of 40 and a detection limit (LOD, defined as 3 s/b) of 7.4 ng L-1 were achieved along with the sampling frequency of 21 h(-1), a sample loading time of 170 s, and a sample consumption of 2.8 mL. The relative standard deviation (RSD) was 2.1% for mu g L-1 Al(III) level. The developed method was performed for the determination of Al(III) in dialysis concentrates. The results of the analysis of the certified reference material (CRM 403) are in good agreement with the certified value. (C) 2015 Elsevier B.V. All rights reserved.