FGF-2 is often an additive to stem cells culture media aimed at preserving the differentiation potential of stem cells through higher passages. Its bioactivity is triggered by binding two classes of receptors: high-affinity fibroblast growth factor receptors and low-affinity receptors – heparin and heparan sulfate proteoglycans (HSPG). The sulfation degree and positioning in HSPG play a crucial role in these processes. In this work, we have prepared synthetic mimics of HSPG with different content of –SO3H and –OH groups. Mixed self-assembled monolayers were prepared by co-adsorption of HS(CH2)11OH and HS(CH2)11SO3H at different ratios (0.00, 0.25, 0.75 and 1.00). The interaction between these surfaces and FGF- 2 was studied in situ by QCM-D: in the presence of –OH groups the adsorbed mass increases with the rise of the –SO3H surface fraction. This mass increase is not a function of FGF-2 concentration but the kinetics of the process is concentration-dependent. Surfaces containing only –SO3H groups demonstrated unexpected behaviour: a lower amount of FGF- 2 was detected for these substrates as compared to the ones with -SO3H surface fraction of 0.75. The bioactivity of FGF-2 was tested by its interactions with anti-FGF-2 and decreases in the following order: -SO3H(0.75) > -SO3H(1.00) >> -SO3H(0.25) > -SO3H(0.00). Finally, we investigated the impact of these interactions on adipose-derived stem cells (ASCs) morphology. We found that in addition to spindle-like cellular morphology, the exogenous FGF-2 induces significantly more and longer filopodia in ASCs cultured on –SO3H rich surfaces.