In this study, the precipitation effi ciency, kinetics, and mechanism of the fractional precipitation for the purifi cation of 

paclitaxel were investigated using glass beads to increase the surface area to volume ratio of the reaction solution (S/V). 

The yield of paclitaxel increased proportionally to the S/V to the power of 0.1 ( Y ∝ (S/V )

0.1

 ) . The maximum yield 

(~ 92%) was achieved after 10 min of precipitation at the optimal S/V (0.21 mm − 1 ). This yield was a 2.28-fold increase 

compared to conventional fractional precipitation. This precipitation method was effi cient because hydrogen bonds are 

formed between the glass bead molecules and paclitaxel molecules during fractional precipitation, and the glass bead 

surface acts as a heterogeneous nucleation site. The paclitaxel purity increased by approximately 20% as the precipitation 

time increased, but it was hardly aff ected by S/V. By applying the precipitation data to a pseudo-second-order model, a 

model was proposed that can predict the surface area to volume ratio of the reaction solution (S/V) and the concentration 

of precipitated paclitaxel (C t

 ) as a function of the operating time (t). Furthermore, a good fi t between the experimental 

and predicted data was confi rmed.