Evaluation of Polyhedral Oligomeric Silsesquioxane Porphyrin Derivatives on Photodynamic Therapy

Abstract

Polyhedral oligomeric silsesquioxane (POSS) is a promising scaffold to be used as delivery system. POSS can modify the properties of photosensitizers to enhance their efficacy toward photodynamic therapy (PDT). In this work, we designed, synthesized and characterized five different POSS porphyrin (POSSPs 1–5) derivatives containing hydrophobic (1–3) and hydrophilic (4 and 5) functional groups. In general, all the POSSPs showed a better singlet oxygen quantum yield than the parent porphyrins due to the steric hindrance from the POSS unique structure. POSSPs 1 and 3 containing isobutyl groups showed better PDT performance in cancer cells at lower concentrations than POSSPs 4 and 5. However; at higher concentrations, the POSSP4 containing hydrophilic groups has an enhanced PDT efficiency as compared with the parent porphyrin. We envision that the chemical tunability of POSSs can be used as a promising option to improve the delivery and performance of photosensitizers.

Light-Activated Protoporphyrin IX-Based Polysilsesquioxane Nanoparticles Induce Ferroptosis in Melanoma Cells

“…Recently, ferroptosis has also been associated with PDT [ 16 , 24 , 25 ]. Our group has focused on the development of PSilQ nanoparticles as a photosensitizer-delivery platform for PDT [ 5 , 6 , 7 , 8 , 9 , 26 ]. We have already demonstrated that PSilQ nanoparticles carrying PpIX as a photosensitizer induce phototoxicity through apoptotic and necrotic cell death mechanisms [ 8 ].…”

Use of Polyhedral Oligomeric Silsesquioxane (POSS) in Drug Delivery, Photodynamic Therapy and Bioimaging

“…Using this approach, our group synthesized octa(aminopropyl)-POSS using APTES as a silica precursor. The octa(aminopropyl)-POSS was reacted with carboxy(phenyl)-triphenyl porphyrin via an amidation reaction to afford a porphyrin-POSS molecule [27]. Also, Hörner and co-workers used octa(aminopropyl)-POSS as a starting material to be modified with fluorescent tetramethyl-rhodamide.…”

“…For instance, our group used this strategy to afford aminopropyl-hepta(isobutyl)-or aminopropyl-hepta(phenyl)-POSS from the corresponding trisilanol POSS precursors. These molecules were further modified to finally obtain porphyrin-POSS molecules [27]. Using the corner capping strategy, Ervithayasuporn and co-workers reacted 3-chloropropyltrhichlorosilane with hepta(isobutyl)-trisilanol POSS to obtain a cage with only one chloropropyl functionality, that was later subjected to an azidation with excess NaN 3 in DMF-THF (93% yield).…”

“…Carbon nanotubes/paclitaxel/anitbody Propyl ammonium chloride Amidation [41] Carbon dots Aminopropyl Amidation [42] BODIPY Propyl ammonium chloride Amidation [43] Fluorescein Azidopropyl Amidation/CuAAC [33] Gluconolactone/dansyl chloride Aminopropyl Sulfonamide bond [44] Tetraphenyl porphyrin Aminoproppyl Amidation, urea bond [27] Ce6/PEG Aminopropyl Amidation [45] Fluorescein labeled dipeptide Propyl ammonium chloride Amidation [46] DOX Succinic anhydride Amidation [47] DOX/PEG Succinic anhydride Amidation [48] Porphyrin Vinyl and hydroxyl Amidation and CuAAC [49] Porphyrin/OPVEs Vinyl and hydroxyl Amidation and CuAAC followed by Heck coupling [50] FITC/carboxylic acid Aminopropyl and isobutyl Amidation [31] Perfluorinated alkyl/silica nanoparticles or fluorophore Propyl ammonium chloride Amidation 2008, 2009, 2012, 2011 [51][52][53][54] Peptide/Ce6 Malemic acid Amidation [55] Protoporphyrin IX/linolenic acid Propyl ammonium chloride Amidation [56] Quantum dots Propyl ammonium chloride Amidation [57] Quantum dots Mercaptoropyl Capping agent [58] Ferrocene Hydrido or hydridodimethylsiloxy Karstedt's catalyzed reaction [59] Quaternized PDMA-poly (sulfobetaíne) Propyl ammonium chloride ARTP [60] Poly (fluorinated acrylate -PEG) Vinyl RAFT polymerization [61] Galactose or maltose Aminopropyl Amidation [66] Glycosides Vinyl Thiol-ene click reaction [67] Various carbohydrates Azidopropyl CuAAC [68] Sugar alkynes Azidopropyl CuAAc 2010, 2012 [18,69] Glycosides/Cysteine derivatives Vinyl Thiol-ene click reaction [70] Poly (lactic acid) Hydroxypropyl Microwave assisted ROMP [71] BODIPY Azidopropyl CuAAC [18] PVF Vinyl Heck couple reaction [72] Dipeptides or tripept...…”

“…Our group has also functionalized POSS molecules containing different substituents linked to a porphyrin photosensitizer [27]. A series of five POSS-porphyrin derivatives were synthesized containing different types of moieties in the POSS cage (Figure 6).…”