Molybdenum Trioxide Nanoparticles with Intrinsic Sulfite Oxidase Activity

Abstract

Sulfite oxidase is a mitochondria-located molybdenum-containing enzyme catalyzing the oxidation of sulfite to sulfate in the amino acid and lipid metabolism. Therefore, it plays a major role in detoxification processes, where defects in the enzyme cause a severe infant disease leading to early death with no efficient or cost-effective therapy in sight. Here we report that molybdenum trioxide (MoO3) nanoparticles display an intrinsic biomimetic sulfite oxidase activity under physiological conditions, and, functionalized with a customized bifunctional ligand containing dopamine as anchor group and triphenylphosphonium ion as targeting agent, they selectively target the mitochondria while being highly dispersible in aqueous solutions. Chemically induced sulfite oxidase knockdown cells treated with MoO3 nanoparticles recovered their sulfite oxidase activity in vitro, which makes MoO3 nanoparticles a potential therapeutic for sulfite oxidase deficiency and opens new avenues for cost-effective therapies for gene-induced deficiencies.

Quantum‐Dot‐Mediated Controlled Synthesis of Dual Oxides of Molybdenum from MoS2: Quantification of Supercapacitor Efficacy

“…[40] Furthermore, the chemical bonding environment of QDs has been evaluated by XPS.T he XPS survey spectrum of QDs ( ure S2 in the Supporting Information) reveals four distinct peaks at 231.7, 233,2 34.8, and 236.2 eV.T he peaks at 231.7 and 234.8 are assigned to the + 5o xidation state of molybdenum, corresponding to Mo 3d 5/2 and Mo 3d 3/2 electrons,r espectively.S imilarly,t he peaks at 233 and 236.2 eV are allocated to the + 6o xidation state, corresponding to Mo 3d 5/2 and Mo 3d 3/2 electrons, respectively. [39,[42][43][44][45][46] Furthermore, the solutiono fQ Ds shows excitation-dependentP Lb ehavior, as generally observed for QD systems ( Figure 3f). [41] The deconvoluted O 1s peaks (Figure 3e)s uggest three types of bondingf or 530.5, 531.6, and 532.6 eV,c orresponding to Mo=O, MoÀOH, and MoÀperoxol inkages, respectively; [42] this confirms the formation of H 2 MoO 5 ·H 2 OQ Ds.…”

“…The solution of QDs shows as trong absorption band at l = 217 nm (Figure 3f), whicha rises from the MoÀOl igand to metal charge transfer. [39,[42][43][44][45][46] Furthermore, the solutiono fQ Ds shows excitation-dependentP Lb ehavior, as generally observed for QD systems ( Figure 3f). [47] The crystal growth processes of MoO 3 and MoO 2 from H 2 MoO 5 ·H 2 OQ Ds during hydrothermalt reatment are elaborated in Scheme 2.…”

Mitochondria-Targeting Particles

“…Recently, it was shown in vitro that molybdenum trioxide NPs, when functionalized with TPP, could confer sulfite oxidase activity to a cultured liver cell line (HepG2) with knocked down sulfite oxidase [83]. It was suggested that these mitochondrial-targeting particles may be used as a therapy for infants with molybdenum cofactor deficiency or sulfite oxidase deficiency.…”

Self-templated formation of aptamer-functionalized copper oxide nanorods with intrinsic peroxidase catalytic activity for protein and tumor cell detection

“…Enzyme-like nanomaterials (nanozymes) [1,2] based on metallic [3][4][5], metal oxide [6][7][8][9][10], bimetallic nanoparticles (NPs) and nanoclusters (NCs) [11][12][13][14], carbon nanomaterials [15][16][17], and hybrid nanocomposites [18][19][20][21][22][23][24][25], have recently received a great deal of attention for their biochemical applications. Enzyme-mimicking molecules (e.g., metal complexes, hemin and other porphyrins, cyclodextrins, and supramolecules) also have been reported to have many advantages over natural enzymes [26][27][28].…”