Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published January 2009 | public
Journal Article

Shape Induced Inhibition of Phagocytosis of Polymer Particles

Abstract

Purpose. To determine if particle shape can be engineered to inhibit phagocytosis of drug delivery particles by macrophages, which can be a significant barrier to successful therapeutic delivery. Methods. Non-spherical polystyrene particles were fabricated by stretching spherical particles embedded in a polymer film. A rat alveolar macrophage cell line was used as model macrophages. Phagocytosis of particles was assessed using time-lapse video microscopy and fluorescence microscopy. Results. We fabricated worm-like particles with very high aspect ratios (>20). This shape exhibits negligible phagocytosis compared to conventional spherical particles of equal volume. Reduced phagocytosis is a result of decreasing high curvature regions of the particle to two single points, the ends of the worm-like particles. Internalization is possible only at these points, while attachment anywhere along the length of the particles inhibits internalization due to the low curvature. Conclusions Shape-induced inhibition of phagocytosis of drug delivery particles is possible by minimizing the size-normalized curvature of particles. We have created a high aspect ratio shape that exhibits negligible uptake by macrophages.

Additional Information

© 2009 Springer. Received March 10, 2008; accepted May 5, 2008; published online June 12, 2008. Authors acknowledge Alejandro Sanchez, Santosh Gupta, and Poornima Kolhar for assistance. JAC acknowledges a graduate fellowship from the National Science Foundation. This research was supported by the Program of Excellence in Nanotechnology by the National Institutes of Health. Electronic supplementary material The online version of this article (doi:10.1007/s11095-008-9626-z) contains supplementary material, which is available to authorized users.

Additional details

Created:
August 22, 2023
Modified:
October 17, 2023