In the present study, asymptotic solutions for particle moment and standard deviation due to Brownian coagulation have been obtained analytically, using a specific moment-based formulation known as the Taylor-series expansion method of moment (TEMOM). The derivation is rigorous, and the accuracy of the asymptotic solution is fully dependent on underlying approximations in an expanded Taylor series. The accuracy has been validated by a comparison with numerical results. The asymptotic solutions reveal that the long-time particle moments are an explicit exponential function of time and first particle moment. (c) 2013 Elsevier Ltd. All rights reserved.