Microgels are soft, colloidal hydrogel particles that are used in biological applications,. These gel particles are made of poly-n-isopropylacrylamide (NIPAM) and are capable of changing volume, in response to their environment. The microgel particles can also be copolymerized with acrylic acid (AAC), which provide a means for bioconjugating biomolecules of interest to the surface of the microgel particles. In this work, microgel bioconjugation was explored by using carbodiimide cross linking chemistry to bind a fluorophore, Alexa Flur 488 Cadaverine, to the surface of synthesized NIPAM – co – AAC [90:10] microgel particles. EDC (1-ethyl-3-[3-dimethylaminopropyl]carbodiimide) and sulfo-NHS (N-hydroxysolfosuccinimide) were first added, to initiate the reaction and form stable intermediate compounds. The bioconjugation reaction was completed after the sulfo-NHS functional groups were exchanged for a peptide bond, formed between the microgel particle and the fluorophore. After the bioconjugation experiments, the efficacy of the reaction was ascertained by measuring the intensity values of the fluorescence signal, measured from the bioconjugated microgel particles. The fluorescence intensities were measured on a fluorescence microscope. The results from our experiments will aid in the our future investigation on uncovering the interfacial properties between microgel particles and flat surfaces, with the future intent to develop them into biosensors.
