The present invention provides compositions comprising at least one biologically active agent (D) chemically conjugated to a peptide or oligopeptide with overall hydrophilicity (Pep). In some embodiments, the composition comprises D-Pep wherein the biologically active agents are linked to the Pep molecule via an chemical linker, such as amino acid linker. These compositions can be mixed with the other compositions to provide mixtures of nanofiber hydrogel structures that also can be used to locally deliver biologically active agents to tissues of interest. The methods and compositions disclosed herein are useful for sustained drug release when administered in situ to the tissue of interest.