title: Biomineralized anisotropic gold microplate-macrophage interactions reveal frustrated phagocytosis-like phenomenon: a novel paclitaxel drug delivery vehicle.
abstract: This study reports a facile biomineralization route for gold microplates (GMPs) synthesis using bovine serum albumin (BSA) as a reductant and stabilizing agent. Adding BSA to HAuCl4 solution yields spontaneous versatile anisotropic and partially hollow GMPs upon aging. We hypothesize that the instantaneous protein denaturation at low pH enabled access to serine and threonine hydroxyl, and sulfhydryl groups of BSA, which act as a reductant and stabilizer, respectively. This reaction could be hastened by increasing the temperature well beyond 65 °C. Transmission electron microscopy/X-ray diffraction studies revealed highly crystalline and anisotropic structures (triangle, pentagon, and rectangle). Atomic force microscopy/scanning electron microscopy analyses demonstrated unique morphology of microplates with a partially void core and BSA mineralized edge structure. RAW 264.7 mice peritoneal macrophage-microplate interaction studies using live cell confocal imaging reveal that cells are capable of selectively internalizing smaller GMPs. Large GMPs are preferentially picked with sharp vertices but cannot be internalized and exhibit frustrated phagocytosis-like phenomenon. We explored particle phagocytosis as an actin mediated process that recruits phagosome-like acidic organelles, shown by a lysosensor probe technique. The biocompatible GMPs exhibited ∼70% paclitaxel (PCL) loading and sustained release of PCL, showing antitumor activity with the MCF-7 cell line, and could be a novel drug carrier for breast cancer therapy.
authors.affiliation: Department of Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute , Troy, New York 12180, United States.
authors.forename: Ajay Vikram
authors.initials: AV
authors.lastname: Singh
authors.forename: Madu
authors.initials: M
authors.lastname: Batuwangala
authors.forename: Ruchir
authors.initials: R
authors.lastname: Mundra
authors.forename: Krunal
authors.initials: K
authors.lastname: Mehta
authors.forename: Sanket
authors.initials: S
authors.lastname: Patke
authors.forename: Ermelinda
authors.initials: E
authors.lastname: Falletta
authors.forename: Rajendra
authors.initials: R
authors.lastname: Patil
authors.forename: W N
authors.initials: WN
authors.lastname: Gade
mesh_terms: D000818:Animals; D002417:Cattle; D002460:Cell Line; D016503:Drug Delivery Systems / Q000379:methods*; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D017239:Paclitaxel / Q000008:administration & dosage / Q000737:chemistry*; D010587:Phagocytosis / Q000502:physiology*; D012710:Serum Albumin, Bovine / Q000737:chemistry
chemical_list: D012710:Serum Albumin, Bovine; D017239:Paclitaxel