Mesoporous silicon particles as intravascular drug delivery vectors: fabrication, in‐vitro, and in‐vivo assessments

Abstract

Porous silicon is an attractive biomaterial for drug delivery thanks to its biocompatibility, biodegradability, ease of fabrication, tunable nanostructure, and porous network. Herein we briefly present the development of a multi‐stage delivery vector that leverages these advantages to enhance delivery of systemically administered therapeutic agents. We illustrate the rational design, objective‐oriented fabrication and geometric control of first stage porous silicon microparticles. We describe how geometry affects the biodistribution of first stage vectors and how their porous structure affects the loading and release of second stage theranostic payloads. We describe the mechanism of cellular internalization and intracellular trafficking of particles. Finally we present two multi‐stage vector prototypes for the delivery of magnetic resonance imaging contrast agents and small interfering RNA (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Tailoring Porous Silicon for Biomedical Applications: From Drug Delivery to Cancer Immunotherapy

“…As for microparticles, the circulation time and the organ accumulation are size and shape dependent . After 4 h from the injection, the particles were mainly found in liver and spleen, with minimal distribution to lung, heart, and kidneys;[19a] the particles distributed in the whole body during the first min, then accumulated within the RES, and ended up in the liver …”

Advances in Porous Silicon–Based Nanomaterials for Diagnostic and Therapeutic Applications

“…Although centrifugation and filtration allow for a narrow size selection, precise fabrication of pSi in a discoidal geometry has been studied which provide certain advantages. One of the reported advantages is that discoidal particles behave differently under flow that cannot be observed with spherical particles . In this specific shape, the particles are more prone to margination toward blood vessel walls, improving the accumulation of the particles in disease sites and enhances its biodistribution 1a,21.…”

Multistage vector (MSV) therapeutics

“…The particles are then subjected to sonication in isopropanol to release them from the silicon substrate. For large-scale production, a multilayer stack procedure can be employed, in which silicon pillars are formed through deep anisotropic etching [9, 10]. Silicon nitride can then be deposited on the entire substrate and the silicon on top of the pillar subjected to reactive-ion etching in fluorocarbon plasma.…”