Hydrogel with ROS scavenging effect encapsulates BR@Zn-BTB nanoparticles for accelerating diabetic mice wound healing via multimodal therapy.

The strategies for eliminating excess reactive oxygen species (ROS) or suppressing inflammatory responses on the wound bed have proven effective for diabetic wound healing. In this work, a zinc-based nanoscale metal-organic framework (NMOF) functions as a carrier to deliver natural product berberine (BR) to form BR@Zn-BTB nanoparticles, which was, in turn, further encapsulated by hydrogel with ROS scavenging ability to yield a composite system of BR@Zn-BTB/Gel (denoted as BZ-Gel). The results show that BZ-Gel exhibited the controlled release of Zn2+ and BR in simulated physiological media to efficiently eliminated ROS and inhibited inflammation and resulted in a promising antibacterial effect. In vivo experiments further proved that BZ-Gel significantly inhibited the inflammatory response and enhanced collagen deposition, as well as to re-epithelialize the skin wound to ultimately promote wound healing in diabetic mice. Our results indicate that the ROS-responsive hydrogel coupled with BR@Zn-BTB synergistically promotes diabetic wound healing.

Kinetically and thermodynamically controlled one-pot growth of gold nanoshells with NIR-II absorption for multimodal imaging-guided photothermal therapy.

Since the successful clinical trial of AuroShell for photothermal therapy, there is currently intense interest in developing gold-based core-shell structures with near-infrared (NIR) absorption ranging from NIR-I (650-900 nm) to NIR-II (900-1700 nm). Here, we propose a seed-mediated successive growth approach to produce gold nanoshells on the surface of the nanoscale metal-organic framework (NMOF) of UiO-66-NH2 (UiO = the University of Oslo) in one pot. The key to this strategy is to modulate the proportion of the formaldehyde (reductant) and its regulator / oxidative product of formic acid to harness the particle nucleation and growth rate within the same system. The gold nanoshells propagate through a well-oriented and controllable diffusion growth pattern (points → facets → octahedron), which has not been identified. Most strikingly, the gold nanoshells prepared hereby exhibit an exceedingly broad and strong absorption in NIR-II with a peak beyond 1300 nm and outstanding photothermal conversion efficiency of 74.0%. Owing to such superior performance, these gold nanoshells show promising outcomes in photoacoustic (PA), computed tomography (CT), and photothermal imaging-guided photothermal therapy (PTT) for breast cancer, as demonstrated both in vitro and in vivo.

A pH-responsive metal-organic framework for the co-delivery of HIF-2α siRNA and curcumin for enhanced therapy of osteoarthritis.

The occurrence of osteoarthritis (OA) is highly correlated with the reduction of joint lubrication performance, in which persistent excessive inflammation and irreversible destruction of cartilage dominate the mechanism. The inadequate response to monotherapy methods, suboptimal efficacy caused by undesirable bioavailability, short retention, and lack of stimulus-responsiveness, are few unresolved issues. Herein, we report a pH-responsive metal-organic framework (MOF), namely, MIL-101-NH2, for the co-delivery of anti-inflammatory drug curcumin (CCM) and small interfering RNA (siRNA) for hypoxia inducible factor (HIF-2α). CCM and siRNA were loaded via encapsulation and surface coordination ability of MIL-101-NH2. Our vitro tests showed that MIL-101-NH2 protected siRNA from nuclease degradation by lysosomal escape. The pH-responsive MIL-101-NH2 gradually collapsed in an acidic OA microenvironment to release the CCM payloads to down-regulate the level of pro-inflammatory cytokines, and to release the siRNA payloads to cleave the target HIF-2α mRNA for gene-silencing therapy, ultimately exhibiting the synergetic therapeutic efficacy by silencing HIF-2α genes accompanied by inhibiting the inflammation response and cartilage degeneration of OA. The hybrid material reported herein exhibited promising potential performance for OA therapy as supported by both in vitro and in vivo studies and may offer an efficacious therapeutic strategy for OA utilizing MOFs as host materials.

AIE-based gold nanostar-berberine dimer nanocomposites for PDT and PTT combination therapy toward breast cancer.

We designed and synthesized three new berberine-based compounds, namely, pyridine-2,6-dimethyl-/2,2'-bipyridine-3,3'-dimethyl-tethered berberine dimers BD1 and BD2, and a tetrakis(4-benzyl)ethylene linked berberine tetramer BD4. We identified that the dimer BD2 and tetramer BD4, as well as 1,10-phenanthroline-2,9-dimethyl-linked berberine dimer BD3 previously reported by us, showed remarkable aggregation-induced emission (AIE) properties which endowed them with higher singlet oxygen (1O2) production ability than berberine. Of the four compounds, BD3 exhibits the lowest ΔEST energy with the highest 1O2 generation ability and thus was selected for further construction of AuNSs-BD3@HA (denoted as ABH, AuNSs = gold nanostars; HA = hyaluronic acid). The nanosystem of ABH shows a remarkable therapeutic effect toward breast cancer by combining photodynamic therapy (PDT) from BD3, photothermal therapy (PTT) from AuNSs, and the CD44-targeting capability of HA. The synergistically enhanced PDT and PTT induce superior cancer cell apoptosis/necrosis in vitro and anti-breast cancer activity in vivo. This study provides a new concept for PDT using natural product derivatives and their combination with PTT for efficient treatment of tumors.

Convenient synthesis of zwitterionic calcium(II)-carboxylate metal organic frameworks with efficient activities for the treatment of osteoporosis.

Calcium supplementation is effective in alleviating the process of osteoporosis and the occurrence of osteoporotic fractures for people with long-term calcium deficiency. Herein, five water-stable calcium carboxylate compounds, that is, mononuclear coordination compound [Ca(Cbdcp)(H2O)6]·0.5H2O (1, H3CbdcpBr = N-(4-carboxybenzyl)-(3,5-dicarboxyl)pyridinium bromide), and metal organic frameworks (MOFs) {[Ca3(Dcbdcp)2(H2O)12]·2H2O}n (2, H4DcbdcpBr = N-(3,5-dicarboxybenzyl)-(3,5-dicarboxyl)pyridinium bromide), {[Ca(Cmdcp)(H2O)4]·3H2O}n (3, H3CmdcpBr = N-carboxymethyl-(3,5-dicarboxyl)pyridinium bromide), {[Ca(Cdcbp)]·2H2O}n (4, H3CdcbpBr = 3-carboxyl-(3,5-dicarboxybenzyl)-pyridinium bromide) and {[Ca0.5(Cmcp)]·2H2O}n (5, H2CmcpBr = N-carboxymethyl-(3-carboxyl)pyridinium bromide), were synthesized from the reaction of CaCl2 with five different kinds of zwitterionic carboxylate ligands in the presence of NaOH, respectively. Compounds 1-5 were characterized by Fourier-transform infrared (FTIR) spectroscopy, elemental analyses, single-crystal X-ray crystallography, and inductively coupled plasma mass spectrometry (ICP-MS). Compound 1 features a mononuclear structure and MOF 2 with a one-dimensional (1D) structure while MOFs 3 and 5 with 2D layer structures and MOF 4 showing a 3D structure. Compounds 1-5 exhibited good water stability and possessed considerable biocompatibility with primary mice osteoblasts. The in vitro ability of compounds 1-5 in regulating osteoblastic differentiation was studied via alkaline phosphatase (ALP) staining, alizarin red S (ARS) staining, and quantitative real-time polymerase chain reaction (qPCR). Among these 5 compounds, MOF 4 showed the overall best in vitro osteogenic effects. Then, we administrated MOF 4 intragastrically to bilaterally ovariectomized mice for 8 weeks and found that bone loss caused by ovariectomy (OVX) was significantly alleviated. Besides, MOF 4 administration showed no toxic effects in the main organs of the mice. Altogether, zwitterionic carboxylate ligands-based calcium compounds provide a new strategy for calcium agents development.

Chemical constituents from Canarium album Raeusch and their anti-influenza A virus activities.

Two new dyhydrophaseic acid glucoside isomers, (1'S, 3'R, 5'S, 8'R, 2Z, 4E)-dihydrophaseic acid-3'-O-ß-D-glucopyranoside (2) and (1'R, 3'S, 5'R, 8'R, 2Z, 4E)-dihydrophaseic acid-3'-O-ß-D-glucopyranoside (4), together with 10 known compounds [myo-inositol (1), 3,4-dihydroxybenzoic acid (3), 3-O-galloyl quinic acid (5), ellagic acid (6), gallic acid (7), ethyl gallate (8), scopoletin (9), ellagic acid-4-O-ß-D-glucopyranoside (10), ellagic acid-4-O-α-L-rhamnopyranoside (11), and isocorilagin (12)] were isolated from the chloroform extract of Canarium album Raeusch fruits by repeated chromatography on macroporous adsorption resin, silica gel, Sephadex LH-20, Toyopearl HW-40F, and reverse-phase C18 columns, etc. Their structures and absolute configurations were determined by comprehensive analysis of 1D- and 2D-nuclear magnetic resonance (NMR), high-resolution electron spray ionization mass spectrometry (HR-ESI-MS), ESI-MS, optical rotation, circular dichroism spectra, and comparison of NMR data with data of known compounds. Bioassay of their anti-influenza virus A activities showed that compounds 9 and 12 displayed a significant inhibitory effect with IC50 values of 22.9 ± 3.7 and 5.42 ± 0.97 µg/ml, respectively.

Sequence-specific fluorometric recognition of HIV-1 ds-DNA with zwitterionic zinc(II)-carboxylate polymers.

Four water-stable zwitterionic zinc-carboxylate polymers are prepared by reacting N-carboxymethyl-(3,5-dicarboxy)-pyridinium bromide (H3CmdcpBr) with zinc(II) nitrate in the presence of NaOH, through adjusting the solvents and ancillary ligands. With H2O as the solvent and the absence of an ancillary ligand, a two-dimensional (2D) polymer network [Zn(Cmdcp)(H2O)]n (1) is formed. In a mixed H2O/DMF solvent and with the presence of chelating ligands 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) and 2-(4-pyridyl)benzimidazole (pbz), a one-dimensional (1D) polymer of {[Zn2(Cmdcp)(bipy)2(H2O)5](NO3)2·3H2O}n (2), a mononuclear ionic species of [Zn(phen)(H2O)4][Cmdcp] (3), and a 2D polymer of {[Zn(Cmdcp)(pbz)][pbz]·7H2O}n (4) are accordingly formed. Compounds 1-4 are characterized by IR, elemental analyses and single crystal X-ray crystallography. Compound 2 strongly adsorbs single-stranded DNA (ss-DNA) probe (denoted as P-DNA) labeled with carboxyfluorescein (FAM) and quenches its fluorescence via a photo-induced electron transfer process. If, however, a double-stranded DNA (ds-DNA) of the human immunodeficiency virus 1 (HIV-1 ds-DNA) is further present, the P-DNA interacts with the major groove in HIV-1 ds-DNA via Hoogsteen hydrogen bonding to form a rigid triplex structure. This results in partial or complete fluorescence recovery depending on the concentration of HIV-1 ds-DNA. The findings are applied in fluorometric sensing of HIV-1 ds-DNA. The calibration plot is linear in the 0-60nM target DNA concentration range, with a 7.4nM detection limit (at a signal-to-noise ratio of 3). The assay is highly specific and not interfered by one base pair mutated for complementary target HIV-1 ds-DNA, complementary ss-DNA, single-base pair mutated for complementary ss-DNA, non-specific ss-DNA sequences, and higher-order dimeric G-quadruplexes.

A zinc(II)-based two-dimensional MOF for sensitive and selective sensing of HIV-1 ds-DNA sequences.

Coordination reaction of a known three-dimensional (3D) polymer precursor {Na3[Na9(Cbdcp)6(H2O)18]}n (A, Cbdcp = N-(4-carboxybenzyl)-(3,5-dicarboxyl)pyridinium) with Zn(NO3)2·6H2O in H2O or H2O/DMF at 100 °C and in the presence of aspirin, 5-fluorouracil (5-FU) as modulators, trans-1,2-bis(4-pyridyl)ethylene (bpe) or 1,2-bis(4-pyridyl)ethane (bpea) as ancillary ligands afforded six novel Zn(II)-based metal-organic frameworks (MOFs), that is, {[Zn(Cbdcp)(H2O)3]·H2O}n (1, 1D zigzag chain), {[Zn(HCbdcp)2]·H2O}n (2, 2D sheet), {[Zn(Cbdcp)(bpe)1/2]·2H2O}n (3, 3D polymer), {[Zn(Cbdcp)(bpe)1/2]·2H2O}n (4, 2D network), {[Zn(Cbdcp)(bpea)1/2]·2H2O}n (5, 3D polymer) and {[Zn(Cbdcp)(bpea)1/2]·2H2O}n (6, 2D network). Among them, compound 2 contains aromatic rings, positively charged pyridinium, Zn(2+) cation centers and carboxylic acid groups lined up on the 2D sheet structure with a certain extended surface exposure. The unique structure of 2 facilitates effective association with carboxyfluorescein (FAM) labeled probe single stranded DNA (probe ss-DNA, delineates as P-DNA) to yield a P-DNA@2 system, and leads to fluorescence quenching of FAM via a photoinduced electron transfer process. The P-DNA@2 system is effective and reliable for the detection of human immunodeficiency virus 1 ds-DNA (HIV ds-DNA) sequences and capable of distinguishing complementary HIV ds-DNA from mismatched target sequences with the detection limit as low as 10 pM (S/N = 3).

A zwitterionic 1D/2D polymer co-crystal and its polymorphic sub-components: a highly selective sensing platform for HIV ds-DNA sequences.

Polymorphic compounds {[Cu(dcbb)2(H2O)2]·10H2O}n (2, 1D chain), [Cu(dcbb)2]n (3, 2D layer) and their co-crystal {[Cu(dcbb)2(H2O)][Cu(dcbb)2]2}n (4) have been prepared from the coordination reaction of a 2D polymer [Na(dcbb)(H2O)]n (1, H2dcbbBr = 1-(3,5-dicarboxybenzyl)-4,4'-bipyridinium bromide) with Cu(NO3)2·3H2O at different temperatures in water. Compounds 2-4 have an identical metal-to-ligand stoichiometric ratio of 1 : 2, but absolutely differ in structure. Compound 3 features a 2D layer structure with aromatic rings, positively charged pyridinium and free carboxylates on its surface, promoting electrostatic, π-stacking and/or hydrogen-bonding interactions with the carboxyfluorescein (FAM) labeled probe single-stranded DNA (probe ss-DNA, delineates as P-DNA). The resultant P-DNA@3 system facilitated fluorescence quenching of FAM via a photoinduced electron transfer process. The P-DNA@3 system functions as an efficient fluorescent sensor selective for HIV double-stranded DNA (HIV ds-DNA) due to the formation of a rigid triplex structure with the recovery of FAM fluorescence. The system reported herein also distinguishes complementary HIV ds-DNA from mismatched target DNA sequences with the detection limit of 1.42 nM.