Most of the literature in this field is largely focused on the properties of bulk (liquid) materials, with less emphasis based on building substrate models, despite the latter's perhaps equal importance in numerous practical applications such as in laundry detergency, home and personal care products, emulsion and foam stability, and industrial separation processes. Indeed, even the basic question of how to parametrise substrates in chemically-specific DPD models has received scant attention to date. Whilst a few studies exist exploring the role of structure and patterns, and heterogeneity, studies which look to build chemically specific surface models (in DPD) do not yet appear in the literature. Here, we start to lay some foundations in this area by providing the basic building blocks for achieving some degree of specificity.