beta-cyclodextrin (beta-CD) functionalized CdTe quantum dots (QDs) were prepared with beta-CD and mercaptopropionic acid (MPA) as the stabilizers (denoted as beta-CD-MPA-CdTe). The QDs capped with the dual stabilizers, beta-CD and MPA, not only showed improved electrochemiluminescence (ECL) efficiency and higher ECL intensity due to the effective removal of the nonradiative surface state and deep surface trap of the QDs, but also exhibited selective response toward benzo[a]pyrene (BaP) as a consequence of specific host-guest interaction between the beta-CD and BaP, resulting in decreased ECL of the QDs. On the basis of the quenching effect of BaP on the ECL of beta-CD-MPA-CdTe QDs, a sensitive and selective method for the determination of BaP was developed. Under optimal conditions, a linear range from 87 pM to 10 nM with a detection limit of 29 pM (S/N = 3) was obtained for the detection of BaP. (C) 2015 Elsevier Ltd. All rights reserved.