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Remedying a multidrug-resistant (MDR) bacteria wound infection is a major challenge due to the inability of conventional antibiotics to treat such infections against MDR bacteria. Thus, developing wound dressings for wound care, particularly against MDR bacteria, is in huge demand. Here, we present a strategy in designing wound dressings: we use a small molecule (6-aminopenicillanic acid, APA)-coated gold nanoparticles (AuNPs) to inhibit MDR bacteria. We dope the AuNPs into electrospun fibers of poly(ε-caprolactone) (PCL)/gelatin to yield materials that guard against wound infection by MDR bacteria. We systematically evaluate the bactericidal activity of the AuNPs and wound-healing capability via the electrospun scaffold. APA-modified AuNPs (Au_APA) exhibit remarkable antibacterial activity even when confronted with MDR bacteria. Meanwhile, Au_APA has outstanding biocompatibility. Moreover, an in vivo bacteria-infected wound-healing experiment indicates that it has a striking ability to remedy a MDR bacteria wound infection. This wound scaffold can assist the wound care for bacterial infections.

A celling point: A mixed self‐assembled monolayer comprising two types of alkanethiols—one containing an azobenzene unit terminated with a peptide, the other containing a hexa(ethylene glycol) group that resists nonspecific cell adhesion—enables cell adhesion to be modulated photochemically. The reversible conversion of the azobenzene moiety between E and Z configurations allows the surface to either support or resist cell adhesion.

Cancer is a disease of complex genetic alterations, and comprehensive genetic diagnosis is beneficial to match each patient to appropriate therapy. However, acquisition of representative tumor samples is invasive and sometimes impossible. Circulating tumor DNA (ctDNA) is a promising tool to use as a non-invasive biomarker for cancer mutation profiling. Here we implemented targeted next generation sequencing (NGS) with a customized gene panel of 382 cancer-relevant genes on 605 ctDNA samples in multiple cancer types. Overall, tumor-specific mutations were identified in 87% of ctDNA samples, with mutation spectra highly concordant with their matched tumor tissues. 71% of patients had at least one clinically-actionable mutation, 76% of which have suggested drugs approved or in clinical trials. In particular, our study reveals a unique mutation spectrum in Chinese lung cancer patients which could be used to guide treatment decisions and monitor drug-resistant mutations. Taken together, our study demonstrated the feasibility of clinically-useful targeted NGS-based ctDNA mutation profiling to guide treatment decisions in cancer.

No abstract

This study uses metal–organic frameworks (MOFs) alone without any added antibacterial ingredients as the nonantibiotic agent for photodynamic therapy (PDT) of chronic wounds infected by multidrug‐resistant (MDR) bacteria. Nanoparticles (NPs) of MOFs (PCN‐224) are incorporated with titanium through a facile cation exchange strategy. The obtained bimetallic PCN‐224(Zr/Ti) shows greatly enhanced photocatalytic performance for the generation of reactive oxygen species under visible light, which is responsible for the effective antibacterial activities. The PCN‐224(Zr/Ti) NPs are loaded onto lactic‐co‐glycolic acid nanofibers to prepare a wound dressing, which shows high biocompatibility and minimal cytotoxicity. The wound dressing is efficient for PDT‐based in vivo healing of the chronic wound infected by MDR bacteria. Most importantly, this work does not involve any additional antibacterial agents, which is facile, low cost, and in particular, greatly explores the potential of MOFs as a powerful nonantibiotic agent in PDT.

A simple and label-free colorimetric method for cadmium ions (Cd 2+ ) detection using unmodified gold nanoparticles (AuNPs) is reported. The unmodified AuNPs easily aggregate in a high concentration of NaCl solution, but the presence of glutathione (GSH) can prevent the saltinduced aggregation of AuNPs. When Cd 2+ is added to the stable mixture of AuNPs, GSH, and NaCl, Cd 2+ can coordinate with 4× GSH as a spherical shaped complex, which decreases the amount of free GSH on the surface of gold nanoparticles to weaken the stability of AuNPs, and AuNPs will easily aggregate in high-salt conditions. On the basis of the mechanism, we design a simple, label-free colorimetric method using AuNPs accompanied by GSH in a high-salt environment to detect Cd 2+ in water and digested rice samples.A s an important natural element, cadmium is widely used in many fields, such as industry, agriculture, and so on. 1 However, chronic exposure of Cd 2+ has caused many serious environmental and health problems, including renal dysfunction, reduced lung capacity, and some cancers. 2,3 In 2013, the government test indicated that some rice samples in South China were contaminated with cadmium. In China, the maximum permitted concentration for cadmium in rice has been set at a level of 0.2 mg/kg, 4 which is lower than the standard of Codex Alimentarius Commission (CAC), but these events are people alarming. Thus, sensitive sensing cadmium in rice is of considerable significance for food safety and human health. Though many methods for Cd 2+ detection have been developed, these methods either are time-consuming or require costly instruments and complicated operation. 5−9 To satisfy the requirement of an on-site and quick testing, a facile, simple, and on-site method for monitoring Cd 2+ is, therefore, still required.Nowadays, many colorimetric detection methods based on gold nanoparticles (AuNPs) or silver nanoparticles have been well developed because these nanoparticles have extremely high extinction coefficients and strong distance-dependent optical properties. 10−17 However, there are very few colorimetric methods for Cd 2+ detection, and the selectivity and sensitivity of those detection methods of Cd 2+ is not sufficiently good for real-world applications. 18−23 For example, a colorimetric method for Cd 2+ detection is developed with triazole-ester modified silver nanoparticles. This method suffers from complex organic synthesis, long response time, and poor sensitivity. 18 AuNPs cofunctionalized with 6-mercaptonicotinic acid and L-cysteine can sense Cd 2+ with a visible color change. However, Pb 2+ and Cu 2+ show interference with the detection of Cd 2+ . 19 A new test paper for the colorimetric immunosensing Cd 2+ has been constructed by using the Cd 2+ -ethylenediaminetetraacetic acid-bovine serum albumin-AuNPs conjugate. The test paper can be successfully used to detect Cd 2+ in drinking and tap water with almost 100% accuracy. However, the practical application is not included in this paper. 22 A new colorimetric met...

A simple and one-pot method for the synthesis of water-soluble, redemitting, highly fluorescent gold nanoparticles has been reported using 11-mercaptoundecanoic acid (11-MUA) as the protecting group. We found that the fluorescent gold nanoparticles could selectively detect copper ions in aqueous solution, with a limit of detection of about 87 nM.