A palladium label to monitor nanoparticle-assisted drug delivery of a photosensitizer into tumor spheroids by elemental bioimaging

Abstract

In this study, the cellular uptake of the second generation photosensitizer 5,10,15,20-tetrakis(3-hydroxyphenyl)porphyrin (mTHPP) was investigated using laser ablation coupled to inductively coupled plasma mass spectrometry (LA-ICP-MS) at a spatial resolution of 10 μm. To achieve high sensitivity, the photosensitizer was tagged with palladium. As a tumor model system, a 3D cell culture of the TKF-1 cell line was used. These tumor spheroids were incubated with the Pd-tagged photosensitizer embedded in poly(lactic-co-glycolic acid) (PLGA) nanoparticles to investigate the efficiency of nanoparticle based drug delivery. An accumulation of the drug in the first cell layers of the tumor spheroid was observed. In the case of nanoparticle based drug delivery, a significantly more homogeneous distribution of the photosensitizer was achieved, compared to tumor spheroids incubated with the dissolved photosensitizer without the nanoparticular drug delivery system. The infiltration depth of the Pd-tagged photosensitizer could not be increased with rising incubation time, which can be attributed to the adsorption of the photosensitizer onto cellular components.

Photochemical behavior of biosupramolecular assemblies of photosensitizers, cucurbit[n]urils and albumins

“…8 Many vehicles have been proposed to deliver payloads of drugs such as nanoparticles, quantum dots, proteins, macrocycles, polymers and liposomes, among others. 11 Recent work on DDSs involving photoactive drugs include polymeric nanoparticles, [12][13][14][15] calcium carbonate microparticles, 16 graphene oxide nanosheets, 17 photo-responsive nanocarriers, 18,19 and novel optical fibers which can deliver both the photoactive drug and/or only singlet oxygen. [20][21][22] In spite of the many varieties of DDSs being studied, few of them are being marketed to date.…”

ICP-MS for the analysis at the nanoscale – a tutorial review

“…The porphyrin-based photosensitiser complexed Pd as the central ion and was embedded in poly(lactic-coglycolic acid) nanoparticles with average diameter of 250 nm. 223 Pozebon et al reviewed recent applications of LA-ICP-MS for biological sample analysis including a section on nanoparticle imaging and quantification. They mainly highlighted the fact that the signal response at least in some reported applications was found to depend on nanoparticle size in particular when metal nanoparticles are distributed in organic tissue matrix.…”

Poly(L-Lactide) Bionanocomposites

“…The major biomedical applications of PdNPs include targeted drug delivery [53,54], anti-cancer therapy [55,56], anti-microbial activities [57], biosensors and intracellular analysis-hydrogen sensors [58,59], biocatalysts [60], and catalysis [61]. Graphene oxide (GO) has treated to create an anchoring OH site on the surface of GO.…”