Anisotropic Protein Patterned Microspheres

Mimicking the surface anisotropy of natural systems (e.g. atoms, molecules, proteins and immune cells) by patterning proteins or polymers as “interactive patches” on synthetic substrates is an attractive strategy to achieve unique functional efficiency in applications such as sensors, biomedicine and photonics1. Further, microspheres are an attractive substrate because their shape and size allows them to interact with similarly sized units like biological cells. Yet a method for facile surface patterning of the microspheres is not yet available. Ideally, this technique would include mild conditions during processing while still permitting fine control over size and order of patterns. Recently, we have developed a new dewetting induced lithography technique to accomplish this task on a microsphere surface. We utilize a new self-assembly process to control the orientation of polystyrene (PS) microspheres (as a model particle). Subsequently, we use a scaffold-based protection/deprotection and labeling procedure that produces polymer or protein patterns reproducibly under mild conditions. SEM-EDAX studies indicate that the pattern of PDMS patch formation on the surface is robust. CLSM studies reveal regular and ordered dual protein pattern. We are currently exploring several applications for our dual-labeled particles including drug delivery, immunotherapeutics, catalysis, and photonic applications.

Acknowledgement

Arnold and Mabel Beckman Foundation for funding.

References

(1) Zhang Z, Glotzer, SC, Self-Assembly of Patchy Particles., Nano Letters, 2004, Vol. 4, No. 8, 1407-1413