It is well known that the Drinfeld double $D(H)=H^{*op}\otimes H$ of an Hopf algebra $H$ admits a quasitriangular structure. When $H$ is finitely dimensional, the $R$-matrix can be given by $$R=\sum e^i\otimes e_i$$ where $\{e_i\}$ and $\{e^i\}$ are dual basis for $H$ and $H^*$. But I can hardly find any construction of the $R$-matrix for the infinitely dimensional case. My question is:
How to define a quasitriangular structure for infinitely dimensional Drinfeld double?
Do I just imitate the finitely dimensional case or it is not even true?