New Structure Mass Tag based on Zr-NMOF for Multiparameter and Sensitive Single-Cell Interrogating in Mass Cytometry

Mass cytometry, also called cytometry by time-of-flight (CyTOF), is an emerging powerful proteomic analysis technique that utilizes metal chelated polymer (MCP) as mass tags for interrogating high-dimensional biomarkers simultaneously on millions of individual cells. However, under the typical polymer-based mass tag system, the sensitivity and multiplexing detection ability has been highly restricted. Herein, a new structure mass tag based on a nanometal organic framework (NMOF) is reported for multiparameter and sensitive single-cell biomarker interrogating in CyTOF. A uniform-sized Zr-NMOF (33 nm) carrying 105 metal ions is synthesized under modulator/reaction time coregulation, which is monodispersed and colloidally stable in water for over one-year storage. On functionalization with an antibody, the Zr mass tag exhibits specific molecular recognition properties and minimal cross-reaction toward nontargeted cells. In addition, the Zr-mass tag is compatible with MCP mass tags in a multiparameter assay for mouse spleen cells staining, which exploits four additional channels, m/z = 90, 91, 92, 94, for single-cell immunoassays in CyTOF. Compared to the MCP mass tag, the Zr-mass tag provides an additional fivefold signal amplification. This work provides the fundamental technical capability for exploiting NMOF-based mass tags for CyTOF application, which opens up possibility of high-dimensional single-cell immune profiling, low abundant antigen detection, and development of new barcoding systems.

Rapid spatially-resolved post-synthetic patterning of metal-organic framework films

Reactive inkjet printing was used for fast and facile spatially-controlled post-synthetic patterning of metal-organic framework films. Here, we report use of the reactive inkjet printing technique to rapidly produce patterned electroactive MOF films by covalent attachment of redox-responsive ferrocenyl groups to UiO-66-NH2 on FTO glass. This study paves the way for the wide applicability of reactive printing to MOF film modification.

One Stone Two Birds: Zr-Fc Metal-Organic Framework Nanosheet for Synergistic Photothermal and Chemodynamic Cancer Therapy

Metal-organic frameworks (MOFs) have been identified as promising materials for the delivery of therapeutics to cure cancer owing to their intrinsic porous structure. However, in a majority of cases, MOFs act as only a delivery cargo for anticancer drugs while little attention has been focused on the utilization of their intriguing physical and chemical properties for potential anticancer purposes. Herein for the first time, an ultrathin (16.4 nm thick) ferrocene-based MOF (Zr-Fc MOF) nanosheet has been synthesized for synergistic photothermal therapy (PTT) and Fenton reaction-based chemodynamic (CDT) therapy to cure cancer without additional drugs. The Zr-Fc MOF nanosheet acts not only as an excellent photothermal agent with a prominent photothermal conversion efficiency of 53% at 808 nm but also as an efficient Fenton catalyst to promote the conversion of H₂O₂ into hydroxyl radical (^•OH). As a consequence, an excellent therapeutic performance has been achieved in vitro as well as in vivo through this combinational effect. This work aims to construct an "all-in-one" MOF nanoplatform for PTT and CDT treatments without incorporating any additional therapeutics, which may launch a new era in the investigation of MOF-based synergistic therapy platforms for cancer therapy.

Novel dual ROS-sensitive and CD44 receptor targeting nanomicelles based on oligomeric hyaluronic acid for the efficient therapy of atherosclerosis

Although the clinical usage of drugs administration was raising, the application of nanoparticles encapsulating the hydrophobic drugs with plummy efficiency was very scarce for atherosclerosis (AS) treatment. In this work, a novel dual ROS-sensitive and CD44 receptors targeting amphiphilic carrier material, oligomeric hyaluronic acid-2'-[propane-2,2-diyllbls (thio)] diacetic acl-hydroxymethylferrocene (oHA-TKL-Fc), named HASF, was synthesized and characterized by ¹H-NMR spectra. Then, we combined curcumin (Cur) with HASF into nano-micelles (HASF@Cur micelles) by self-assembling method. The resulting HASF@Cur micelles had the average size of 150.8 nm and zeta potential of -35.04 mV to maintain the will-defined spheroidal structure and stability. Importantly, the HASF@Cur micelles had ultrahigh entrapment efficiency (about 51.41 %). Moreover, in vitro release study, Cur release from HASF@Cur micelles was effective in the reactive oxygen species (ROS) condition, and the release rate was interrelated with the concentration of hydrogen peroxide (H₂O₂). Further, fluorescence imaging showed that the HASF@Cur micelles could more selective access to Raw 264.7 cells than free Cur via oHA-receptor mediated endocytosis. The MTT assay attested the safety of amphiphilic carrier material HASF. Additionally, the results of in vivo Oil red O lipid staining studies showed that the lesion area of the aorta was reduced to 47.3±3.4 % with HASF@Cur micelles, compared with the lesion area of Cur group (63.2±2.7 %), HASF@Cur micelles had the more remarkable effect in reducing lesion area (*P < 0.05). Consequently, the novel dual ROS-sensitive and CD44 receptors targeting drug delivery system would become a promising strategy for atherosclerosis.

Ferrocenyl metal–organic framework hollow microspheres for in situ loading palladium nanoparticles as a heterogeneous catalyst

Zn–Fc MOF hollow microspheres were prepared for the in situ reduction of Pd²⁺ into Pd nanoparticles as a highly efficient heterogeneous catalyst.