Arsenic sorption and speciation with branch-polyethyleneimine modified carbon nanotubes with detection by atomic fluorescence spectrometry

► A novel sorbent for arsenic by modifying carbon nanotubes (MWNTs) with polyethyleneimine (BPEI). ► The MWNTs-BPEI nanocomposites exhibit favorable selectivity to As(V) adsorption. ► It facilitates speciation of As(V) and As(III) by coupling to atomic fluorescence spectrometry.