Microfluidic systems for infectious disease diagnostics.

Microorganisms, encompassing both uni- and multicellular entities, exhibit remarkable diversity as omnipresent life forms in nature. They play a pivotal role by supplying essential components for sustaining biological processes across diverse ecosystems, including higher host organisms. The complex interactions within the human gut microbiota are crucial for metabolic functions, immune responses, and biochemical signalling, particularly through the gut-brain axis.

Acoustofluidic large-scale mixing for enhanced microfluidic immunostaining for tissue diagnostics.

The usage of microfluidics for automated and fast immunoassays has gained a lot of interest in the last decades. This integration comes with certain challenges, like the reconciliation of laminar flow patterns of micro-scale systems with diffusion-limited mass transport. Several methods have been investigated to enhance microfluidic mixing in microsystems, including acoustic-based fluidic streaming.

High-resolution imaging and analysis of the intestinal bacterial load of during early adulthood.

We study the presence within the worm () of a fluorescent strain of the worm's bacterial food ( () OP50) during early adulthood. Use of a microfluidic chip based on a thin glass coverslip substrate allows investigation of the intestinal bacterial load using a Spinning Disk Confocal Microscope (SDCM) equipped with a high-resolution objective (60×). High-resolution z-stack fluorescence images of the gut bacteria in adult worms, which were loaded in the microfluidic chip and subsequently fixed, were analyzed using IMARIS software and 3D reconstructions of the intestinal bacterial load in the worms were obtained.

Microtubule-mediated GLUT4 trafficking is disrupted in insulin-resistant skeletal muscle.

Microtubules serve as tracks for long-range intracellular trafficking of glucose transporter 4 (GLUT4), but the role of this process in skeletal muscle and insulin resistance is unclear. Here, we used fixed and live-cell imaging to study microtubule-based GLUT4 trafficking in human and mouse muscle fibers and L6 rat muscle cells. We found GLUT4 localized on the microtubules in mouse and human muscle fibers.

Correction: Bubble-enhanced ultrasonic microfluidic chip for rapid DNA fragmentation.

Correction for 'Bubble-enhanced ultrasonic microfluidic chip for rapid DNA fragmentation' by Lin Sun , , 2022, , 560-572, https://doi.org/10.1039/D1LC00933H.

Efficient AC electrothermal flow (ACET) on-chip for enhanced immunoassays.

Biochemical reaction rates in microfluidic systems are known to be limited by the diffusional transport of reagents, leading often to lowered sensitivity and/or longer detection times in immunoassays. Several methods, including electrically powering electrodes to generate AC electrothermal flow (ACET) on-chip, have been adopted to enhance the mass transport of the reagents and improve microfluidic mixing. Here, we report a novel ACET electrode design concept for generating in-plane microfluidic mixing vortices that act over a large volume close to the reaction surface of interest.

Multi-photon polymerization using upconversion nanoparticles for tunable feature-size printing.

The recent development of light-based 3D printing technologies has marked a turning point in additive manufacturing. Through photopolymerization, liquid resins can be solidified into complex objects. Usually, the polymerization is triggered by exciting a photoinitiator with ultraviolet (UV) or blue light.

Polydimethylsiloxane microstructure-induced acoustic streaming for enhanced ultrasonic DNA fragmentation on a microfluidic chip.

Next-generation sequencing (NGS) is an essential technology for DNA identification in genomic research. DNA fragmentation is a critical step for NGS and doing this on-chip is of great interest for future integrated genomic solutions. Here we demonstrate fast acoustofluidic DNA fragmentation ultrasound-actuated elastic polydimethylsiloxane (PDMS) microstructures that induce acoustic streaming and associated shear forces when placed in the field of an ultrasonic transducer.

The enhancement of DNA fragmentation in a bench top ultrasonic water bath with needle-induced air bubbles: Simulation and experimental investigation.

Shearing DNA to a certain size is the first step in many medical and biological applications, especially in next-generation gene sequencing technology. In this article, we introduced a highly efficient ultrasonic DNA fragmentation method enhanced by needle-induced air bubbles, which is easy to operate with high throughput. The principle of the bubble-enhanced sonication system is introduced and verified by flow field and acoustic simulations and experiments.

Bubble-enhanced ultrasonic microfluidic chip for rapid DNA fragmentation.

DNA fragmentation is an essential process in developing genetic sequencing strategies, genetic research, as well as for the diagnosis of diseases with a genetic signature like cancer. Efficient on-chip DNA fragmentation protocols would be beneficial to process integration and open new opportunities for microfluidics in genetic applications. Here we present an acoustic microfluidic chip comprising an array of ultrasound-actuated microbubbles located at dedicated positions adjacent to a channel containing the DNA sample solution.

Ripening of two-dimensional colloidal CdSe nanocrystals into zero-dimensional nanodots.

Understanding the ripening of two-dimensional (2D) colloidal nanocrystals (NCs) is important for the controllable synthesis of NCs with desired morphology and properties. In this study, we systematically investigate the ripening behavior of the 2D CdSe NCs in the presence of a short-chain acetate ligand and a long-chain oleate ligand. We find that a low acetate/oleate ratio, a low Cd/Se ratio, and a low monomer concentration help in the ripening of the 2D NCs to form 0D NCs.

Effect of inoculum size and antibiotics on bacterial traveling bands in a thin microchannel defined by optical adhesive.

Phenotypic diversity in bacterial flagella-induced motility leads to complex collective swimming patterns, appearing as traveling bands with transient locally enhanced cell densities. Traveling bands are known to be a bacterial chemotactic response to self-generated nutrient gradients during growth in resource-limited microenvironments. In this work, we studied different parameters collective migration, in particular the quantity of bacteria introduced initially in a microfluidic chip (inoculum size) and their exposure to antibiotics (ampicillin, ciprofloxacin, and gentamicin).

An In Vivo Microfluidic Study of Bacterial Load Dynamics and Absorption in the Intestine.

() has gained importance as a model for studying host-microbiota interactions and bacterial infections related to human pathogens. Assessing the fate of ingested bacteria in the worm's intestine is therefore of great interest, in particular with respect to normal bacterial digestion or intestinal colonization by pathogens. Here, we report an in vivo study of bacteria in the gut of .

Antimicrobial susceptibility testing by measuring bacterial oxygen consumption on an integrated platform.

Cellular respiration is a fundamental feature of metabolic activity and oxygen consumption can be considered as a reliable indicator of bacterial aerobic respiration, including for facultative anaerobic bacteria like . Addressing the emerging global health challenge of antimicrobial resistance, we performed antimicrobial susceptibility testing using the bacterial oxygen consumption rate (OCR) as a phenotypic indicator. We demonstrated that microbial exposure to antibiotics showed systematic OCR variations, which enabled determining minimum inhibitory concentrations for three clinically relevant antibiotics, ampicillin, ciprofloxacin, and gentamicin, within a few hours.

Fast antimicrobial susceptibility testing on by metabolic heat nanocalorimetry.

Fast spreading of antimicrobial resistance is now considered a major global health threat. New technologies are required, enabling rapid diagnostics of bacterial infection combined with fast antimicrobial susceptibility testing (AST) for evaluating the efficiency and dosage of antimicrobial compounds in vitro. This work presents an integrated chip-based isothermal nanocalorimetry platform for direct microbial metabolic heat measurements and evaluates its potential for fast AST.

An in vivo microfluidic study of bacterial transit in C. elegans nematodes.

Caenorhabditis elegans (C. elegans) constitutes an important model organism for use in nutrition and aging studies. We report a novel method for studying the dynamics of Escherichia coli (E.

Force microscopy of the embryonic eggshell.

Assays focusing on emerging biological phenomena in an animal's life can be performed during embryogenesis. While the embryo of has been extensively studied, its biomechanical properties are largely unknown. Here, we demonstrate that cellular force microscopy (CFM), a recently developed technique that combines micro-indentation with high resolution force sensing approaching that of atomic force microscopy, can be successfully applied to embryos.

Automated phenotyping of embryos with a high-throughput-screening microfluidic platform.

The nematode has been extensively used as a model multicellular organism to study the influence of osmotic stress conditions and the toxicity of chemical compounds on developmental and motility-associated phenotypes. However, the several-day culture of nematodes needed for such studies has caused researchers to explore alternatives. In particular, embryos, due to their shorter developmental time and immobile nature, could be exploited for this purpose, although usually their harvesting and handling is tedious.

PDMS filter structures for size-dependent larval sorting and on-chip egg extraction of C. elegans.

C. elegans-based assays require age-synchronized populations prior to experimentation to achieve standardized sets of worm populations, due to which age-induced heterogeneous phenotyping effects can be avoided. There have been several approaches to synchronize populations of C.

Microfluidic system for Caenorhabditis elegans culture and oxygen consumption rate measurements.

Mitochondrial respiration is a key signature for the assessment of mitochondrial functioning and mitochondrial dysfunction is related to many diseases including metabolic syndrome and aging-associated conditions. Here, we present a microfluidic Caenorhabditis elegans culture system with integrated luminescence-based oxygen sensing. The material used for the fabrication of the microfluidic chip is off-stoichiometry dual-cure thiol-ene-epoxy (OSTE+), which is well-suited for reliably recording on-chip oxygen consumption rates (OCR) due to its low gas permeability.

Microfluidics-assisted multiplexed biomarker detection for in situ mapping of immune cells in tumor sections.

Because of the close interaction between tumors and the immune system, immunotherapies are nowadays considered as the most promising treatment against cancer. In order to define the diagnosis and the subsequent therapy, crucial information about the immune cells at the tumor site is needed. Indeed, different types or activation status of cells may be indicative for specific and personalized treatments.

Microfluidic-based immunohistochemistry for breast cancer diagnosis: a comparative clinical study.

Breast cancer is a highly heterogeneous disease. The efficacy of tailored therapeutic strategies relies on the precise detection of diagnostic biomarkers by immunohistochemistry (IHC). Therefore, considering the increasing incidence of breast cancer cases, a concomitantly time-efficient and accurate diagnosis is clinically highly relevant.

Spontaneous Formation of CdSe Photoluminescent Nanotubes with Visible-Light Photocatalytic Performance.

Two-dimensional (2D) colloidal CdSe nanocrystals (NCs) with precise atomic-scale thickness have attracted intensive attention in recent years due to their optical properties and quantum confinement effects originating from their particular band structure. Here, we report a solution-based and template-free protocol to synthesize CdSe nanotubes (NTs) having 3-6 walls, each of which has 3.5 molecular monolayers.