Microporous Drug‐Eluting Large Silk Particles Through Cryo‐Granulation
Abstract
A facile method for the preparation of large, microporous, drug‐loaded particles is presented. High shear bollus injections of silk with cross‐linker and drug colloids into super‐cooled hexane are utilized to trigger phase separation of silk droplets, followed by immediate freezing at –60 °C. A subsequent –20 °C freeze‐thaw of the frozen droplets resulted in self‐assembly (crystallization) of the silk. The silk particles developed an internal interconnected microporous morphology with 0.1–10 μm in diameter pores. The silk particles ranged in diameter from 100 to 1300 μm, with particle mean diameter and polydispersity controlled by the starting concentration of the cross‐linking agent and silk, the rheology of the reaction mixture, and the injection pressure (80–300 kPa). Cryogranulation provided a one‐step process to produce microporous meso‐scale silk particles with encapsulated drugs, such as doxorubicin chloride (DoxR), tobramycin sulfate (TS), kanamycin sulfate (KS), or gentamicin sulfate (GS). Almost 100% drug encapsulation efficiency is achieved in the process, and subsequent release profiles depended on the starting concentration of both the drug, silk, and pH of the elution medium. Kirby–Bauer tests and bioluminescent imaging confirmed the retention of anti‐bacterial potency of the antibiotics pre‐encapsulated in the cryo‐particles, and macroparticles cytocompatibility toward human fibroblast and kidney cells.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 18, 2019
- Source ID
- 10.1002/adem.201801242
Entities
People
- David L. Kaplan
- Ilia Rodionov
- Nadia Abdullah
Organizations
- Air Force Office of Scientific Research
- National Institutes of Health
- Tufts University