**3. Results and Discussion**

We have recently developed an effective protocol for the preparation and characterization of (co)oligoesters containing bioactive moieties that were linked as pendant groups along oligomer backbones. The purpose of the current research was the preliminary assessment of the developed (co)oligoesters for their use as controlled DS for p-AA. The objects of this study were as follows: (p-AA-CH2-HP)n (sample 1; see Section 2.1. Materials) oligoester and [(p-AA-CH2-HP)x-co-(HB)y] (co)oligoesters (sample 2, see Section 2.1. Materials) containing p-AA (as the bioactive end and side groups) connected to the polymer backbone through the susceptible to hydrolysis and ester bonds [25].