Latest ArticlesTumor heterogeneity plays a critical role in the determination of appropriate anticancer therapy. As circulating tumor cells (CTCs) contain all tumor-related information, the genetic changes on CTCs could help us choose the appropriate treatments for different patients. Single-base mutations are very common in tumor genetic changes which may result in drug resistance. Here, we introduce a single-cell mutation detection platform based on droplet microfluidics. This platform integrates cell capsulation, cell lysis, polymerase chain reaction (PCR) and the observation process. The droplets' generation speed is over 6000 per minute and more than 600 cells could be encapsulated in one second. To verify the performance of our platform in practical use, we performed the mutation analysis of 4 kinds of cells with our platform and noted that the genetic status of each single cell was clearly discriminated. Moreover, these results agreed with those from direct sequencing. Compared with other forms of single-cell mutation detection techniques, our platform has high throughput, short experimental time and less experimental operations.
Two-dimensional (2D) materials composed of single pnictogen element, namely, 2D pnictogens (e.g., black phosphorus, arsenene, antimonene and bismuthine), have recently showed remarkable potential for biomedical applications, especially after the rapid development of black phosphorus. With unique optical and electronic properties, 2D pnictogens are considered as promising nanoagents for biosensors, diagnosis and therapy. In this review, after brief introduction of the structure, properties, synthesis strategies, and biocompatibility of 2D pnictogens, their biomedical applications including anti-tumor, anti-inflammation, anti-bacterial, neurodegenerative treatment and tissue repairing are reviewed. The major obstacles and opportunities of 2D pnictogens are also discussed. This review provides a short yet timely summary on the synthesis and biomedical applications of emerging 2D pnictogens.
With the development of nanotechnology and materials science, bioinspired nanochannels appeared by mimicking the intelligent functions of biological ion channels. They have attracted a great deal of attention in recent years due to their controllable structure and tunable chemical properties. Inspired by the layered microstructure of nacre, 2D layered materials as excellent matrix material of nanochannel come into our field of vision. Bionic nanochannels based on 2D materials have the advantages of facile preparation, tunable channel size and length, easy expansion, and modification, etc. Therefore, the 2D layered nanofluid system based on bionic nanochannels from 2D layered materials has great potential in biomimetic microsensors, membrane separations, energy conversion, and so on. In this paper, we focus on the construction and application of bionic nanochannels based on 2D layer materials. First, a basic understanding of nanochannels based on 2D materials is briefly introduced, we also present the property of the 2D materials and construction strategies of bionic nanochannels. Subsequently, the application of these nanochannels in responsive channels and energy conversion is discussed. The unsolved challenges and prospects of 2D materials-based nanochannels are proposed in the end.
Adjusting the electronic structure of graphitic carbon nitride (g-C3N4) photocatalyst through π-π conjugation is an effective method to achieve efficient photogenerated carrier separation. One key challenge of π-π conjugation control is to tune the degree of such conjugation without destroying the g-C3N4 structure. Herein we report a conceptual design that achieves a coplanar heterojunction by enhancing the π-π conjugation via the doping of crystalline g-C3N4 using a conjugated double bond ring molecule, 1,3,5-benzenetriol, during calcination process. The selection of the dopant enables the facile creation of a unique coplanar heterojunction which not only retains the pristine network structure of g-C3N4, but remarkably promotes separation and transfer of photogenerated carriers through the enhanced π-conjugated endogenous electric field. As a result, the new g-C3N4 photocatalyst efficiently photocatalytically produces hydrogen from water under visible light irradiation with a high H2 production rate up to 94.94 μmol/h, and a notable external quantum efficiency of 16.4% at 420 nm.
Developing phosphors with long-lifetime (millisecond scale or even longer) solid state room temperature phosphorescence (RTP) feature has attracted considerable attention. However, to date, stimuli-responsive phosphors with RTP nature are still rare due to the absence of effective guidelines for the exploitation of luminophors synchronously possessing stimuli-responsive and RTP characteristics. In this work, a series of mononuclear gold(I) complexes are reported. All these complexes exhibit various solid-state RTP properties, and phosphor 1-Cl exhibits long-lived RTP behavior. The effect of halogen atoms on the RTP nature of these complexes is investigated in detail. Furthermore, the introduction of different types of halogen atoms can effectively regulate the phosphorescent mechanochromism phenomena of these gold(I)-containing complexes. In addition, these phosphors display typical aggregation-induced emission (AIE) effect except for phosphor 5-CCl, which lacks hydrogen-bonding interactions compared with the other four phosphors. This work will be very helpful to the development of mechanical-force-responsive AIE phosphors with lasting RTP.
The first total synthesis of dracaenins A and B is achieved in four steps. The synthesis features the convergent coupling of three readily available fragments with minimized use of protecting groups. The chemical synthesis enables the discovery of their activity in stimulating platelet aggregation, and thus, sheds light on the possible origin of the hemostatic effect of dragon's blood.
By combining 5, 10, 15, 20-tetra(4-chlorine)phenylporphyrin (TClPP) and α-Keggin polyoxometalate H5PV2Mo10O40 (H5PVMo) via a simple ion-exchange method, an organic-inorganic hybrid material [C44H28N4Cl4]1.5[H2PMo10V2O40]·2C2H6O (H2TClPP-H2PVMo) was prepared and thoroughly characterized by a variety of techniques. The homogeneous photocatalytic degradation of 2-chloroethyl ethyl sulfide (CEES) (5 µL) by H2TClPP-H2PVMo (1 × 10−6 mol/L) was studied in methanol and methanol-water mixed solvent (v/v = 1:1), in which the degradation rate of CEES reached 99.52% and 99.14%, respectively. The reaction followed first-order reaction kinetics, and the half-life and kinetic constant in methanol and the mixed solvent were respectively 33.0 min, −0.021 min−1 and 15.7 min, −0.043 min−1. Mechanism analysis indicated that under visible light irradiation in the air, CEES was degraded via oxidation and alcoholysis/hydrolysis in methanol and the mixed solvent. O2·− and 1O2 generated by H2TClPP-H2PVMo selectively oxidized CEES into a nontoxic sulfoxide. Singlet oxygen capture experiments showed that H2TClPP-H2PVMo (ϕ = 0.73) had a higher quantum yield of singlet oxygen than TClPP (ϕ = 0.35) under an air atmosphere and visible light irradiation.
An efficient chlorination reaction of in situ generated (β-diazo-α, α-difluoroethyl)phosphonates has been achieved with hydrochloric acid as a chlorine source under mild and operationally convenient conditions. The reaction does not need any catalyst and tolerates a wide scope of substrates, which affords the (β-chlorodifluoroethyl)phosphonate products in good to excellent yields. This reaction represents the first example of the halogenation of difluoroalkyl diazo compounds, and also provides an easy way for the synthesis of difluoromethylenephosphonate-containing compounds.
A linear supramolecular polymer with controllable features based on twisted cucurbit[14]uril (tQ[14]) and cucurbit[8]uril (Q[8]) was firstly fabricated via an effective self-sorting strategy. Herein we designed a monomer, 1-butyl-1′-(naphthalen- 2-ylmethyl)-4, 4′-bipyridinium bromide (BNB), that contains bipyridyl, aliphatic butyl and aromatic naphthyl groups, simultaneously. Two host molecules, tQ[14] and Q[8] were employed to develop an effective strategy for constructing a linear supramolecular polymer with controllable features. The alkyl groups on both sides of BNB could insert into the two cavities of tQ[14], the naphthyl part of BNB via π-π stacking in Q[8] cavity, serving as the driving force for supramolecular polymerization. Through self-sorting of the monomer, tQ[14] and Q[8], led to the formation of the linear supramolecular polymer. Depolymerization could be achieved by addition of adamantane hydrochloride (AH) which driven two BNB guest molecules out of the Q[8] cavity. This self-sorting strategy has great potential, not only for designing supramolecular polymer materials with different controllable structures through introduction of multiple functional groups, but also for broadening the application of twisted cucurbit[14]uril in supramolecular chemistry.
Chemodynamic therapy (CDT), defined as an in situ oxidative stress response catalyzed by the Fenton or Fenton-like reactions to generate cytotoxic hydroxyl radicals (•OH) at tumor sites, exhibits conspicuous inhibition of tumor growth. It has attracted extensive attention for its outstanding edge in effectiveness, lower systemic toxicity and side effects, sustainability, low cost and convenience. However, the inconformity of harsh Fenton reaction conditions and tumor microenvironment hamper its further development, based on which, numerous researchers have made efforts in further improving the efficiency of CDT. In this review, we expounded antitumor capacity of CDT in mechanism, together with its limitation, and then summarized and came up with several strategies to enhance CDT involved tumor therapy strategies by 1) improving catalytic efficiency; 2) increasing hydrogen peroxide levels at tumor sites; 3) reducing glutathione levels at tumor sites; 4) applying external energy intervention; 5) amplifying the distribution of hydroxyl radicals at tumor sites; and 6) combination therapy. Eventually, the perspectives and challenges of CDT are further discussed to encourage more in-depth studies and rational reflections.