Tracking the Fate of Porous Silicon Nanoparticles Delivering a Peptide Payload by Intrinsic Photoluminescence Lifetime

Abstract

A nanoparticle system for systemic delivery of therapeutics is described, which incorporates a means of tracking the fate of the nanocarrier and its residual drug payload in vivo by photoluminescence (PL). Porous silicon nanoparticles (PSiNPs) containing the proapoptotic antimicrobial peptide payload, [KLAKLAK] , are monitored by measurement of the intrinsic PL intensity and the PL lifetime of the nanoparticles. The PL lifetime of the PSiNPs is on the order of microseconds, substantially longer than the nanosecond lifetimes typically exhibited by conventional fluorescent tags or by autofluorescence from cells and tissues; thus, emission from the nanoparticles is readily discerned in the time-resolved PL spectrum. It is found that the luminescence lifetime of the PSiNP host decreases as the nanoparticle dissolves in phosphate-buffered saline solution (37 °C), and this correlates with the extent of release of the peptide payload. The time-resolved PL measurement allows tracking of the in vivo fate of PSiNPs injected (via tail vein) into mice. Clearance of the nanoparticles through the liver, kidneys, and lungs of the animals is observed. The luminescence lifetime of the PSiNPs decreases with increasing residence time in the mice, providing a measure of half-life for degradation of the drug nanocarriers.

Response of Photoluminescence of H-Terminated and Hydrosilylated Porous Si Powders to Rinsing and Temperature

“…Porous silicon has garnered significant interest in the past several decades due to its relevance to rechargeable lithium ion batteries [1][2][3][4], sensing [5][6][7][8], and biomedical applications including drug delivery [9][10][11], as a vaccine adjuvant [12], in theranostics [13,14], and as a functional biomaterial [15]. When nanostructured, silicon becomes a biocompatible material [16,17].…”

Hierarchical Nanostructuring of Porous Silicon with Electrochemical and Regenerative Electroless Etching

“…In addition, the process can be used to considerably increase the SSA of the material, to tune the size of the remaining silicon skeleton structure and, thereby, to enhance the PL with respect to emission color and intensity. Strong PL combined with its resorbable nature are essential for use of PSi particles in bioimaging, in particular, time-gated PL imaging and as a self-reporting material in drug delivery , and smart bandages for which PSi is particularly well suited.…”

Overcoming Barriers: Clinical Translation of siRNA Nanomedicines

“…entrapped siRNA molecules into the porous structure, capping the open‐ended pores with an organic layer of calcium silicate ( Figure A,B). [ 137 ] The versatility of this unique self‐sealing method was also demonstrated in the delivery of antibiotics, [ 138 ] peptides, [ 139 ] and miRNA. [ 140 ] Further on, the Sailor group investigated coating the siRNA‐loaded calcium silicate pSiNPs with a lipid bilayer, obtaining a fusogenic nanoparticle.…”