Showing papers by "Leigh T. Canham published in 2015"
TL;DR: It is shown that the ability of porous silicon to act as an effective carrier for sustained delivery of antibacterial agents can be sensitively altered by surface functionalization.
Abstract: Nanostructured mesoporous silicon possesses important properties advantageous to drug loading and delivery. For controlled release of the antibacterial drug triclosan, and its associated activity versus Staphylococcus aureus, previous studies investigated the influence of porosity of the silicon matrix. In this work, we focus on the complementary issue of the influence of surface chemistry on such properties, with particular regard to drug loading and release kinetics that can be ideally adjusted by surface modification. Comparison between drug release from as-anodized, hydride-terminated hydrophobic porous silicon and the oxidized hydrophilic counterpart is complicated due to the rapid bioresorption of the former; hence, a hydrophobic interface with long-term biostability is desired, such as can be provided by a relatively long chain octyl moiety. To minimize possible thermal degradation of the surfaces or drug activity during loading of molten drug species, a solution loading method has been investigate...
23 citations
30 Jun 2015
TL;DR: In this paper, supercritical drying of ultrahigh porosity (90%) porous silicon is shown to preserve much higher mesopore volumes (up to 4mL/g) and surface areas than achievable with standard air drying.
Abstract: Biodegradable porous silicon (pSi) is under assessment for the controlled release of both proteins and poorly-soluble API formulations. Super-critical drying of ultrahigh porosity (90%) porous silicon is shown here to preserve much higher mesopore volumes (up to 4mL/g) and surface areas (up to 600m2M/g) than achievable with standardair drying. The payloads and physical state of the model drug (S) (+) ibuprofen, as loaded within a super-critically dried porous silicon carrier matrix,were quantified and assessed using TGA, DSC, cross-sectional EDX, XRD, Raman mapping andFT-IR. In-vitro biodegradability was assessed using Mmolybdenum blue assay and drug release using RPHPLC. Entrapped drug payloads as high as 70%w/w have been achieved, substantially higher than values reported for other mesoporous materials. The entrapped (S) (+) ibuprofen showed faster release than bulk (S) (+) ibuprofen.
2 citations
Patent•
16 Sep 2015
TL;DR: In this article, the authors proposed a method for delivering therapeutic agents, particularly proteins and antibodies, via a porous silicon-based carrier material impregnated with the therapeutic agent, which can be used in vitro or in vivo to maintain an equilibrium concentration of a therapeutic agent over an intended period of time such as over multiple days, weeks, months, or years.
Abstract: This invention discloses reservoirs, such as implants for delivering therapeutic agents, particularly large molecules such as proteins and antibodies. The reservoirs may comprise a porous silicon-based carrier material impregnated with the therapeutic agent. The reservoir may be used in vitro or in vivo to maintain an equilibrium concentration of a therapeutic agent over an intended period of time such as over multiple days, weeks, months, or years. Additionally, the reservoir may be reloaded with additional therapeutic agent. These reservoirs may be used for treating or preventing conditions of a subject such as chronic diseases.