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The utilization of biocatalytic oxidations has evolved from the niche applications of the early 21st century to a widely recognized tool for general chemical synthesis. One of the major drawbacks that hinders commercialization is the dependence on expensive nicotinamide adenine dinucleotide (NAD(P) + ) cofactors, and so, their regeneration is essential. Here, we report the design of carbon-supported Pt catalysts that can regenerate NAD(P) + by proton-driven NAD(P)H oxidation with concurrent hydrogen formation. The carbon support was modified to tune the electronic nature of the Pt nanoparticles, and it was found that the best catalyst for NAD(P) + regeneration (TOF = 581 h -1 ) was electron-rich Pt on carbon. Finally, the heterogeneous Pt catalyst was applied in the biocatalytic oxidation of a variety of alcohols catalyzed by different alcohol dehydrogenases. The Pt catalyst exhibited good compatibility with the biocatalytic system. Its NAD(P) + regeneration function successfully supported biocatalytic conversion from alcohols to corresponding ketone or lactone products. This work provides a promising strategy for chemical synthesis via NAD(P) + -dependent pathways utilizing a cooperative inorganic-enzymatic catalytic system.

Triple-negative breast cancer (TNBC) has a high rate of metastasis, which is associated with breast cancer stem-like cells (CSCs). Although Taxol (micelle formulation of paclitaxel) is the first line chemotherapy to treat TNBC, it increases CSCs in residual tumors. Abraxane, albumin nanoparticle of paclitaxel, showed lower plasma concentration compared to Taxol in both human and animal models, but it is not clear why Abraxane showed superior efficacy to Taxol in treatment of metastatic breast cancer in humans. In this study, we intend to investigate if Abraxane eliminates CSCs for its better efficacy. The results showed that Abraxane showed similar cytotoxicity in SUM149 cells in comparison with Taxol. Although Abraxane showed 3- to 5-fold lower blood drug concentration compared to Taxol, it achieved similar tumor drug concentration and 10-fold higher tumor/plasma ratio in SUM149 xenograft NOD/SCID mouse model. In addition, Abraxane and Taxol showed similar efficacy to shrink the tumor size in orthotopic breast cancer NOD/SCID mouse model. However, Abraxane decreased breast CSCs frequency by 3- to 9-fold, while Taxol increased breast CSCs frequency in an orthotopic breast cancer NOD/SCID mouse model. Furthermore, Abraxane increased 3- to 15-fold intracellular uptake in both ALDH+ CSCs and differentiated ALDH- cells in comparison with Taxol, which provides a mechanism for Abraxane's superior efficacy to eliminate CSCs in comparison with Taxol. Our data suggest albumin nanoparticle Abraxane may have a broad implication to enhance drug's efficacy by eliminating breast cancer stem cells for treatment of metastatic diseases.

Single crystals of Ln 2 Fe 4- x Co x Sb 5- y Bi y (Ln = La, Ce; 0 ≤ x < 0.5; 0 ≤ y ≤ 0.2) were grown using Bi flux and self-flux methods. The compounds adopt the La 2 Fe 4 Sb 5 structure type with tetragonal space group I4/ mmm. The La 2 Fe 4 Sb 5 structure type is comprised of rare earth atoms capping square Sb nets in a square antiprismatic fashion and two transition-metal networks forming a PbO-type layer with Sb and transition-metal isosceles triangles. Substituting Co into the transition-metal sublattice results in a decrease in the transition temperature and reduced frustration, indicative of a transition from localized to itinerant behavior. In this manuscript, we demonstrated that Bi can be used as an alternate flux to grow single crystals of antimonides. Even with the incorporation of Bi into the Sb square net, the magnetic properties are not significantly affected. In addition, we have shown that the incorporation of Co into the Fe triangular sublattice leads to an itinerant magnetic system.

Single crystals of Pr2Fe(4-x)Co(x)Sb5 (1 < x < 2.5) were grown from a Bi flux and characterized by X-ray diffraction. The compounds adopt the La2Fe4Sb5 structure type (I4/mmm). The structure of Pr2Fe(4-x)Co(x)Sb5 (1 < x < 2.5) contains a network of transition metals forming isosceles triangles. The x ∼ 1 analogue is metallic and exhibits a magnetic transition at T1 ≈ 25 K. The magnetic moment obtained from the Curie-Weiss fit is 11.49(4) μ(B), which is larger than the spin-only Pr(3+) moment. The x ∼ 2 analogue orders magnetically at T1 ≈ 80 and T2 ≈ 45 K. This is the first case of the substitution of Co into the La2Fe4Sb5 structure type, evidenced by the increased concentration of dopant with decreased lattice parameters coupled with a change in the transition temperature with a change in the cobalt concentration. The added complexity in the magnetic behavior of the x ∼ 1 and 2 analogues indicates that the increased concentration of Co invokes an additional magnetic contribution of the transition metal in the sublattice. Furthermore, X-ray photoelectron spectroscopy measurements support the change in the oxidation states of transition metals with increasing cobalt concentration.

Although many techniques exist for fabricating near-infrared (NIR)-resonant and magnetic resonance imaging (MRI)-capable nanomediators for photothermal cancer therapy, preparing them in an efficient and scalable process remains a significant challenge. In this report, we exploit one-step siloxane chemistry to facilely conjugate NIR-absorbing satellites onto a well-developed polysiloxane-containing polymer-coated iron oxide nanoparticle (IONP) core to generate dual functional core-satellite nanomediators for photothermal therapy. An advantage of this nanocomposite design is the variety of potential satellites that can be simply attached to impart NIR resonance, which we demonstrate using NIR-resonant gold sulfide nanoparticles (Au2SNPs) and the NIR dye IR820 as two example satellites. The core-satellite nanomediators are fully characterized by using absorption spectra, dynamic light scattering, ζ potential measurements, and transmission electron microscopy. The enhanced photothermal effect under the irradiation of NIR laser light is identified through in vitro solutions and in vivo mice studies. The MRI capabilities as contrast agents are demonstrated in mice. Our data suggest that polysiloxane-containing polymer-coated IONPs can be used as a versatile platform to build such dual functional nanomediators for translatable, MRI-guided photothermal cancer therapy.