We have recently developed a genetically and chemically-modified α-haemolysin pore for the simultaneous measurement of a range of neurotransmitters, including purines, catecholamines and glutamate (Boersma et al., 2012). Building upon a previous purine-sensitive pore (Cheley et al., 2002), a catecholamine binding side that incorporated Cu2+ allowed several catecholamines, including noradrenaline, adrenaline and dopamine, to bind. These measurements were made in a Cl–free, HCO3–free physiological saline containing (mM): 118 NaCl, 10 MOPS, 4.7 KCl, 1.8 CaCl2, 1.8 MgCl2, 11.1 D-glucose; pH 7.4. When such pores are incorporated into an artificial bilipid membrane, and then voltage-clamped, single molecules of these neurotransmitters can be detected as they block the α-haemolysin pore. The identity of each molecule can be determined my measuring both the amplitude of the conductance block and the dwell time of the molecule on the pore. We have demonstrated the ability of this technique to distinguish separate molecules in a cocktail of ATP (5 µM), ADP (5 µM) and noradrenaline (1µM), and describe a technique for calculating the concentration of each component of the mixture. Glutamate (<5 µM) is also detectable with the same pore. Altering the clamp voltage modifies the relative sensitivity of the pore, which provides an additional method for identifying binding molecules. Such a need might arise if very similar species need to be distinguished. We have tested this probe on the spontaneous and epibatidine-evoked release of transmitters from PC12 cells, and in pilot experiments can simultaneously identify ADP, ATP and noradrenaline, as well as a small set of other binding events for which the chemical species responsible have not yet been identified. The stable nature of α-haemolysin implies that this approach may be developed to produce a relatively simple-to-use method for single-molecule detection of neurotransmitter release in small sample volumes, although several technical challenges remain including the optimization of suitable bilipid membranes (or other methods of supporting the channel), reducing the binding site affinity (to increase the off rate and hence increase the sampling frequency, particularly for catecholamines) and the identification of all biologically relevant binding molecules.