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A range of microgels with two different functionalities were synthesized, and their utility in novel bioapplications was examined. Cationic microgels with varying properties were developed by tuning synthesis conditions. Their size and primary amine content was analyzed, and one microgel system was selected as a model construct. Its primary amine groups were conjugated to two dyes with properties favorable for utilization as contrast agents in photoacoustic imaging. The concentration of contrast agent in single particles was determined. The implications of a high local dye concentration in the generation of high intensity photoacoustic signals, are discussed. The second bioapplication involved the targeted delivery of fibrinolytics to fibrin clots, in order to bring about dissolution of abnormal thrombi. For this purpose, core/shell microgels with carboxylic acid groups in their shells were synthesized in three size ranges. Following this, their dimension based differential localization in and around porous fibrin clots was examined. Fibrin-specific peptides were then conjugated onto the shells of these particles and the conjugates were shown to demonstrate strong interactions with the fibrin clots. The microgels conjugated to the peptide with the highest binding affinity to fibrin, were observed to bring about disruption of fibrin clots, merely through interference in the dynamic interactions among clot fibers, due to the equilibrium nature of the fibrin polymer. The implications of these novel results and future studies required to facilitate a better understanding of the phenomena involved, are discussed.