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The monkeypox virus (MPXV) is a linear double-stranded DNA virus with a large genome that causes tens of thousands of infections and hundreds of deaths in at least 40 countries and regions worldwide. Therefore, timely and accurate diagnostic testing could be an important measure to prevent the ongoing spread of MPXV and widespread epidemics. Here, we designed multiple sets of primers for the target region of MPXV for loop-mediated isothermal amplification (LAMP) detection and identified the optimal primer set. Then, the specificity in fluorescent LAMP detection was verified using the plasmids containing the target gene, pseudovirus and other DNA/RNA viruses. We also evaluated the sensitivity of the colorimetric LAMP detection system using the plasmid and pseudovirus samples, respectively. Besides, we used monkeypox pseudovirus to simulate real samples for detection. Subsequent to the establishment and introduction of a magnetic beads (MBs)-based nucleic acid extraction technique, an integrated device was developed, characterized by rapidity, high sensitivity, and remarkable specificity. This portable system demonstrated a visual detection limit of 137 copies/mL, achieving sample-to-answer detection within 1 h. The device has the advantages of integration, simplicity, miniaturization, and visualization, which help promote the realization of accurate, rapid, portable, and low-cost testing. Meanwhile, this platform could facilitate efficient, cost-effective and easy-operable point-of-care testing (POCT) in diverse resource-limited settings in addition to the laboratory. Fig. Schematic diagram of the integrated assay device. The integrated sample-to-answer device was fabricated with three modules, including nucleic acid extraction, LAMP reaction, and colorimetric readout. [Display omitted] • An integrated visual nucleic acid self-testing device based on LAMP assay. • Efficient enrichment of nucleic acids using Si-OH magnetic beads without elution. • Visual results can be obtained within 1 h using the sample-to-answer device. • The LOD for monkeypox virus nucleic acid is as low as 137 copies/mL. • The LAMP-based self-testing device is suitable for point-of-care testing. [ABSTRACT FROM AUTHOR]

Existing digital polymerase chain reaction (PCR) devices consist of multiple independent devices, such as a droplet generator, a PCR thermocycler, and a droplet reader, which have the disadvantages of low integration, complex equipment structure, and high operation difficulty. This paper proposes a fully automatic integrated digital PCR device based on continuous-flow digital PCR theory. By simply adding the sample to the entrance of the integrated instrument, a series of procedures required for digital PCR detection can be fully automated, including sample injection, droplet generation, PCR thermal cycling, fluorescence acquisition, and signal analysis. In contrast to traditional techniques, sample testing requires only one integrated device rather than three separate instruments. For full automation, we design complete control and data processing software, which can complete a test by one-step operation. Therefore, the disadvantages of traditional instruments, such as multi-step operation, and hence, potential environmental pollution, are avoided. Moreover, the system can be powered by solar cells and does not require an external power supply. As a proof of concept, the proposed device is used for absolute quantitative detection of the hepatitis B virus in serum samples. The capacity of the system is validated by absolute quantification of three orders of magnitude from 103 to 105 IU/mL. The results have a good linear correlation (0.9986) with those of the traditional quantitative (qPCR), thus confirming the reliability of the instrument. In summary, we believe that our work can promote the development of integrated digital PCR systems. Image 1 The highlights of the manuscript as follow: •Single device for digital PCR detection. •Solar cells drive, no external power supply. •A software was designed which can control the system and analyze the data. •Absolute quantitative detection of hepatitis B virus in human serum. [ABSTRACT FROM AUTHOR]

An integrated device of electrodialytic membrane suppressor and charge detector (CHD) for ion chromatography (IC) is described, aiming to simplify system complexity and reduce possible extra-column dispersion as well. The device is a flow-through design consisting of five chambers isolated by ion exchange membranes and ionic screens. Two independent electric sources are used to respectively supply CHD and suppressor sections of the device, and a common electrode serves both the cathode of CHD and the anode of suppressor simultaneously. The integrated device has similar performance as a separate suppressor or a CHD while its dead volume and dispersion are reduced ∼18% and ∼37% compared with the combination of a CHD and a suppressor. To our knowledge, this is the first description of such an integrated device with dual functionalities of suppression and CHD. [ABSTRACT FROM AUTHOR]