In traditional lateral flow immunoassays (LFIA) for pathogens detection, capture antibody (CA) is necessary and usually conjugated to Au nanoparticles (NPs) in order to label the target analyte. However, the acquisition process of the Au–CA nanoprobe is relatively complicated and costly, which will limit the application of LFIA. Herein, p-mercaptophenylboronic acid-modified Au NPs (namely Au–PMBA nanocrabs), were synthesized and applied for a new CA-independent LFIA method. The stable Au–PMBA nanocrabs showed outstanding capability to capture both Gram-negative bacteria and Gram-positive bacteria through covalent bonding. The acquired Au–PMBA–bacteria complexes were dropped onto the strip, and then captured by the detection antibody on the test line (T-line). Take Escherichia coli O157:H7 as an example, the gray value of T-line was proportional to the bacteria concentration and the linear range was 103–107 cfu·mL–1. This CA-independent strategy exhibited higher sensitivity than the traditional CA-dependent double antibody sandwich method, because detection limit of the former one was 103 cfu·mL–1 only by visual observation, which was reduced by 3 orders of magnitude. Besides, this platform successfully screened E. coli O157:H7 in four food samples with recoveries ranging from 90.25% to 107.25%. This CA-independent LFIA showed great advantages and satisfactory potential for rapid foodborne pathogens detection in real samples.

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Psoriasis is a chronic and recurrent skin disease that often requires long‐term treatment, and topical transdermal drug delivery can reduce systemic side effects. However, it is still a challenge in efficient transdermal drug delivery for psoriasis treatment due to low penetration efficiency of most drugs and the abnormal skin conditions of psoriasis patients. Here, a safe and effective methacryloyl chitosan hydrogel microneedles (CSMA hMNs) patch is developed and served as a sustained drug release platform for the treatment of psoriasis. By systematically optimizing the CSMA preparation, CSMA hMNs with excellent morphological characteristics and strong mechanical properties (0.7 N needle−1) are prepared with a concentration of only 3% (w/v) CSMA. As a proof‐of‐concept, methotrexate (MTX) and nicotinamide (NIC) are loaded into CSMA hMNs patch, which can produce a sustained drug release of 80% within 24 h in vitro. In vivo experiments demonstrated that the CSMA hMNs patch can effectively inhibit the skin thickening and spleen enlargement of psoriatic mice and has a good biosafety profile at sufficient therapeutic doses. This study provides a new idea for the preparation of hMN systems using modified CS or other biocompatible materials and offers an effective therapeutic option for psoriasis treatment.This article is protected by copyright. All rights reserved

Helicobacter pylori (H. pylori) is listed as a definite carcinogen and clinical triple therapy is less satisfactory because H. pylori colonizes beneath the gastric mucous layer and easily forms biofilm. More importantly, the frequent and excessive use of antibiotics causes a disorder of gut microbiota due to the lack of targeting to H. pylori. Here, a kind of protonated charge reversal metal based nanodrugs (MNDs)—ZnO‐Ag‐mercaptoacetamide@chitosan for H. pylori eradication treatment without affecting beneficial gut microbiota is prepared. In H. pylori infected mouse model, the MNDs actively target submucosa colonized H. pylori owing to mucous penetrability and protonation effect, and further eradicate H. pylori and its biofilm by producing metal ions and reactive oxygen species. Transcriptomic analysis shows that there are no obvious side effects to intestinal microorganisms during the treatment. Besides, it is found that the MNDs are great potential to remove gastric inflammation along with the blocking of inflammatory pathways and the reduction of virulence factors, which is related to the infiltration of CD4+ T cells to clear H. pylori.

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