The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting.Hence,a method for controlling and removing the...The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting.Hence,a method for controlling and removing the electrical charge needs to be developed.In this study,by using the electrode-deposited pipet tip(E-pipet tip),the charge-controlling system is newly developed and the electrical charge of a droplet is precisely controlled.The effect of electrolyte concentration and volume of the transferred solution to the electrical charge of a dispensed droplet is theoretically and experimentally investigated by using the equivalent capacitor model.Furthermore,a proof-of-concept example of the self-alignment and self-assembly of sequentially dispensed multiple droplets is demonstrated as one of the potential applications.Given that the electrical charge of the various aqueous droplets can be precisely and simply controlled,the fabricated E-pipet tip can be broadly utilized not only as a general charge-controlling platform of aqueous droplets but also as a powerful tool to explore fundamental scientific research regarding electrical charge of a droplet,such as the surface oscillation and evaporation of charged droplets.展开更多
Reliable and comprehensive monitoring data are required to trace and counteract biodiversity loss. Highthroughput metabarcoding using DNA extracted from community samples (bulk) or from water orsediment (environmental...Reliable and comprehensive monitoring data are required to trace and counteract biodiversity loss. Highthroughput metabarcoding using DNA extracted from community samples (bulk) or from water orsediment (environmental DNA) has revolutionized biomonitoring, given the capability to assess biodiversity across the tree of life rapidly with feasible effort and at a modest price. DNA metabarcoding canbe upscaled to process hundreds of samples in parallel. However, while automated high-throughputanalysis workflows are well-established in the medical sector, manual sample processing still predominates in biomonitoring laboratory workflows limiting the upscaling and standardization for routinemonitoring applications. Here we present an automated, scalable, and reproducible metabarcodingworkflow to extract DNA from bulk samples, perform PCR and library preparation on a liquid handler.Key features are the independent sample replication throughout the workflow and the use of manynegative controls for quality assurance and quality control. We generated two datasets: i) a validationdataset consisting of 42 individual arthropod specimens of different species, and ii) a routine monitoringdataset consisting of 60 stream macroinvertebrate bulk samples. As a marker, we used the mitochondrialCOI gene. Our results show that the developed single-deck workflow is free of laboratory-derivedcontamination and produces highly consistent results. Minor deviations between replicates are mostlydue to stochastic differences for low abundant OTUs. Thus, we successfully demonstrated that roboticliquid handling can be used reliably from DNA extraction to final library preparation on a single deck,thereby substantially increasing throughput, reducing costs, and increasing data robustness for biodiversity assessments and monitoring.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIP).(No.2014R1A2A1A010065272011-0030075+1 种基金2012R1A2A2A06047424)supported by the convergence technology development program for bionic arm through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT&Future Planning(No.2014M3C1B2048632)
文摘The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting.Hence,a method for controlling and removing the electrical charge needs to be developed.In this study,by using the electrode-deposited pipet tip(E-pipet tip),the charge-controlling system is newly developed and the electrical charge of a droplet is precisely controlled.The effect of electrolyte concentration and volume of the transferred solution to the electrical charge of a dispensed droplet is theoretically and experimentally investigated by using the equivalent capacitor model.Furthermore,a proof-of-concept example of the self-alignment and self-assembly of sequentially dispensed multiple droplets is demonstrated as one of the potential applications.Given that the electrical charge of the various aqueous droplets can be precisely and simply controlled,the fabricated E-pipet tip can be broadly utilized not only as a general charge-controlling platform of aqueous droplets but also as a powerful tool to explore fundamental scientific research regarding electrical charge of a droplet,such as the surface oscillation and evaporation of charged droplets.
基金This study is a part of the GeDNA project funded by the German Environment Agency(FKZ 3719242040)All members are part of COST Action DNAqua-Net(CA15219)+1 种基金D..B is supported by a grant of the German Research Foundation(DFG,LE 2323/9-1)We thank Kristin Stolberg(LfU)for discussions and permission to use the metabarcoding data.
文摘Reliable and comprehensive monitoring data are required to trace and counteract biodiversity loss. Highthroughput metabarcoding using DNA extracted from community samples (bulk) or from water orsediment (environmental DNA) has revolutionized biomonitoring, given the capability to assess biodiversity across the tree of life rapidly with feasible effort and at a modest price. DNA metabarcoding canbe upscaled to process hundreds of samples in parallel. However, while automated high-throughputanalysis workflows are well-established in the medical sector, manual sample processing still predominates in biomonitoring laboratory workflows limiting the upscaling and standardization for routinemonitoring applications. Here we present an automated, scalable, and reproducible metabarcodingworkflow to extract DNA from bulk samples, perform PCR and library preparation on a liquid handler.Key features are the independent sample replication throughout the workflow and the use of manynegative controls for quality assurance and quality control. We generated two datasets: i) a validationdataset consisting of 42 individual arthropod specimens of different species, and ii) a routine monitoringdataset consisting of 60 stream macroinvertebrate bulk samples. As a marker, we used the mitochondrialCOI gene. Our results show that the developed single-deck workflow is free of laboratory-derivedcontamination and produces highly consistent results. Minor deviations between replicates are mostlydue to stochastic differences for low abundant OTUs. Thus, we successfully demonstrated that roboticliquid handling can be used reliably from DNA extraction to final library preparation on a single deck,thereby substantially increasing throughput, reducing costs, and increasing data robustness for biodiversity assessments and monitoring.
