Jeroen Lammertyn

KU Leuven | ku leuven · Division of Mechatronics, Biostatistics and Sensors (MeBioS)

Several European countries have implemented new legislations to eliminate the killing of day-old male chicks, pushing the laying hen industry to find animal-friendly solutions. Although embryo sexing during incubation ( in ovo sexing) is highly promising, no current solution meets the industry requirements of handling all egg colors with >98 % sexi...

Fiber-optic surface plasmon resonance (FO-SPR) sensors look at the absorbance of reflected light to measure changes in refractive index (RI). FO-SPR sensor modeling is essential in understanding the underlying processes that induce such RI changes. Despite two types of rays, i.e., skew and meridional rays, an FO-SPR model has been developed in the...

Partially fluorinated nanoparticles (FNPs) have been proposed as a promising alternative for stabilising aqueous droplets in fluorinated oils. The exceptional energetic stability of FNPs at the droplet interface holds the potential for minimising leakage, enhancing stability, and promoting improved cell adhesion. However, their lower diffusion coef...

Self-powered microfluidics presents a revolutionary approach to address the challenges of healthcare in decentralized and point-of-care settings where limited access to resources and infrastructure prevails or rapid clinical decision-making is critical. These microfluidic systems exploit physical and chemical phenomena, such as capillary forces and...

Dilution is a standard fluid operation widely employed in the sample preparation process of many bio(chemical) assays. It serves multiple essential functions such as sample mixing with certain reagents at...

In ovo sexing involves identifying chicken embryo sex before or during incubation to avoid euthanizing male chicks after hatching, enhancing animal welfare in the laying hen industry. Recently, researchers demonstrated the potential for non-invasive and early in ovo sexing through the analysis of volatile organic compounds (VOCs) emitted by eggs. H...

Volatile organic compounds (VOCs) carry crucial information on chicken egg fertility. Assessing fertility before incubation holds immense potential for poultry industry efficiency. Our study used headspace sorptive extraction-gas chromatography-mass spectrometry to analyze egg VOCs before and during the initial 12 incubation days. A total of 162 VO...

The culling of day-old male chickens remains an important welfare issue in the poultry industry. Several governments ( e.g. , Germany, France or Italy) have prohibited this practice, pushing the hatcheries to look for alternatives. Although different solutions exist for solving this problem, sex determination during embryo’s incubation (so called i...

Over the past decade, advanced analytical techniques have been utilized to examine volatile organic compounds (VOCs) in eggs. These VOCs offer valuable insights into factors such as freshness, fertility, the presence of cracks, embryo sex, and breed. In our study, we assessed three mass spectrometry-based systems (headspace sorptive extraction gas...

Over the past decade, advanced analytical techniques have been utilized to examine volatile organic compounds (VOCs) in eggs. These VOCs offer valuable insights into factors such as freshness, fertility, the presence of cracks, embryo sex, and breed. In our study, we assessed three mass spectrometry-based systems (headspace sorptive extraction gas...

Therapeutic options to treat bacterial infections caused by Gram-negative pathogens are limited due to the spread of multidrug resistance. Protein engineering of phage-derived lysins can play a key role in the search for new antimicrobial compounds targeting Gram-negative pathogens. A previous high-throughput screen of a combinatorial lysin library...

DNA-based enzymes, or DNAzymes, are single-stranded DNA sequences with the ability to catalyze various chemical reactions, including the cleavage of the bond between two RNA nucleotides. Lately, an increasing interest has been observed in these RNA-cleaving DNAzymes in the biosensing and therapeutic fields for signal generation and the modulation o...

Selected ion flow tube-mass spectrometry (SIFT-MS) is an analytical technique for volatile detection and quantification. SIFT-MS can be applied in a "white box" approach, measuring concentrations of target compounds, or as a "black box" fingerprinting technique, scanning all product ions during a full scan. Combining SIFT-MS full scan data acquired...

Background Thrombotic thrombocytopenic purpura (TTP) is characterized by severe ADAMTS-13 activity deficiency (<10%). Diagnostic testing is challenging because of unavailability, high cost, and expert technician requirement of ADAMTS-13 enzyme assays. Cost-effective, automated fiber-optic surface plasmon resonance (FO-SPR) platforms show potential...

Selected-ion-flow-tube-mass-spectrometry (SIFT-MS) is an analytical technique for volatile detection and quantification. SIFT-MS can be applied in a ‘white box’ approach, measuring concentrations of target compounds, or as a ‘black box’ fingerprinting technique, scanning all product ions during a full scan. Combining SIFT-MS full scan data acquired...

Numerous researchers and institutions have been developing in ovo sexing technologies to improve animal welfare by identifying male embryos in an early embryonic stage and disposing of them before pain perception. This review gives a complete overview of the technological approaches reported in papers and patents by performing a thorough search usi...

Selected-ion-flow-tube-mass-spectrometry (SIFT-MS) is an analytical technique for volatile detection and quantification. SIFT-MS can be applied in a ‘white box’ approach, measuring concentrations of target compounds, or as a ‘black box’ fingerprinting technique, scanning all product ions during a full scan. Combining SIFT-MS full scan data acquired...

Numerous researchers and institutions have been developing in ovo sexing technologies to improve animal welfare by identifying male embryos in an early embryonic stage and disposing of them before pain perception. This review gives a complete overview of the technological approaches reported in papers and patents by performing a thorough search usi...

Front Cover In article number 2201477, Lammertyn and co‐workers developed FLUIDOT, a modular microfluidic platform in which microwells, optical tweezers, and an interchangeable cell‐retrieval system are combined to enable in‐depth screening and specific retrieval of single cells. They demonstrated the versatility of FLUIDOT by implementing applicat...

Microneedles are gaining a lot of attention in the context of sampling cutaneous biofluids such as capillary blood. Their minimal invasiveness and user-friendliness make them a prominent substitute for venous puncture or finger-pricking. Although the latter is suitable for self-sampling, the impracticality of manual handling and the difficulty of o...

Extracellular vesicles (EVs) have attracted great attention as potential biomarkers for cancer diagnostics. Although several technologies have been developed for EV detection, many of them are still not applicable to clinical settings as they rely on complex EV isolation processes, while lacking sensitivity, specificity or standardization. To solve...

This paper present porous polydimethylsiloxane (PDMS) optical phantoms with tunable microstructural and optical properties to mimic porous biological tissues (eg. fruit) during the design and optimization of novel optical setups. A well connected salt network formed using salt particles of various size distributions was used to obtain porous PDMS p...

Throughout the past decades, fiber optic surface plasmon resonance (FO-SPR)-based biosensors have proven to be powerful tools for both the characterization of biomolecular interactions and target detection. However, as FO-SPR signals are generally related to the mass that binds to the sensor surface, multistep processes and external reagents are of...

Advancements in lab‐on‐a‐chip technologies have revolutionized the single‐cell analysis field. However, an accessible platform for in‐depth screening and specific retrieval of single cells, which moreover enables studying diverse cell types and performing various downstream analyses, is still lacking. As a solution, FLUIDOT is introduced, a versati...

In the continuous combat against diseases, there is the need for tools that enable an improved diagnostic efficiency towards higher information density combined with reduced time-to-result and cost. Here, a novel fully integrated microfluidic platform, the Evalution™, is evaluated as a potential solution to this need. Encoded microparticles combine...

Fluorescence in situ hybridization (FISH) is the gold standard for visualizing genomic DNA in fixed cells and tissues, but it is incompatible with live-cell imaging, and its combination with RNA imaging is challenging. Consequently, due to its capacity to bind double-stranded DNA (dsDNA) and design flexibility, the clustered regularly interspaced s...

The need for self-referencing is extremely important in the field of biosensing. In this manuscript, we report on the study, design, and validation of a dual-region self-referencing fiber-optic surface plasmon resonance biosensor. One region is intended to measure and monitor the binding events of the biological sample under test, while the other o...

Picoinjection is a robust method for reagent addition into microfluidic droplets and has enabled the implementation of numerous multistep droplet assays. Although serial picoinjectors allow to screen many conditions in one run by injecting different combinations of reagents, their use is limited because it is complex to accurately control each inje...

Treatment with neutralizing monoclonal antibodies (mAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contributes to COVID-19 management. Unfortunately, SARS-CoV-2 variants escape several of these recently approved mAbs, highlighting the need for additional discovery and development. In a convalescent COVID-19 patient, we id...

Medical diagnostics is moving toward disease-related target detection at very low concentrations because of the (1) quest for early-stage diagnosis, at a point where only limited target amounts are present, (2) trend toward minimally invasive sample extraction, yielding samples containing low concentrations of target, and (3) need for straightforwa...

Disease treatment with advanced biological therapies such as adalimumab (ADM), although largely beneficial, is still costly and suffers from loss of response. To tackle these aspects, therapeutic drug monitoring (TDM) is proposed to improve treatment dosing and efficacy, but is often associated with long sampling-to-result workflows. Here, we prese...

Therapeutic drug monitoring (TDM) of adalimumab (ADM) at the point-of-care (POC) is key to prevent loss of response but has not been accomplished to date because true POC testing solutions are still lacking. Here, we present a novel “whole blood in – result out” self-powered microfluidic chip for detecting ADM within 30 min to enable TDM at POC. He...

Continuous biosensors provide real-time information about biochemical processes occurring in the environment of interest and are therefore highly desirable in research, diagnostics and industrial settings. Although remarkable progress has been made in the field of biosensing, most biosensors still rely on batch processes and, thus, are not suited t...

In recent years, CRISPR-Cas (stands for: clustered regularly interspaced short palindromic repeats - CRISPR associated protein) based technologies have gained increasing attention in the biosensing field. Thanks to excellent sequence specificity, their use is of particular interest for detecting nucleic acid (NA) targets. In this context, signal ge...

Single cell analyses have gained increasing interest over bulk approaches because of considerable cell-to-cell variability within isogenic populations. Herein, flow cytometry remains golden standard due to its high-throughput efficiency and versatility, although it does not allow to investigate the interdependency of cellular events over time. Star...

The ongoing COVID-19 pandemic has emphasized the urgent need for rapid, accurate, and large-scale diagnostic tools. Next to this, the significance of serological tests (i.e., detection of SARS-CoV-2 antibodies) also became apparent for studying patients' immune status and past viral infection. In this work, we present a novel approach for not only...

SARS-CoV-2 B.1.1.529, designated omicron, was recently identified as a new variant of concern by WHO and is rapidly replacing SARS-CoV-2 delta as the most dominant variant in many countries. Unfortunately, because of the high number of mutations present in the spike of SARS-CoV-2 omicron, most monoclonal antibodies (mAbs) currently approved for tre...

Treatment with neutralizing monoclonal antibodies (mAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contributes to COVID-19 management. Unfortunately, SARS-CoV-2 variants can escape several of these recently approved mAbs, highlighting the need for additional discovery and development. In a convalescent COVID-19 patient, w...

Dried blood spot (DBS) sampling by finger-pricking has recently gained a lot of interest as an alternative sample collection method. The reduced invasiveness, requirement of lower sample volumes and suitability for long-term storage at room temperature make DBS ideal for use in home settings or low-resource environments. However, traditional protoc...

We present an innovative multiplexing concept on a fiber optic surface plasmon resonance (FO-SPR) platform and demonstrate for the first time the simultaneous detection of two targets using the same FO sensor probe. Co(III)-NTA chemistry was used for oriented and stable co-immobilization of two different His6-tagged bioreceptors. T2C2 and MDTCS (i....

Spheroids have become essential building blocks for biofabrication of functional tissues. Spheroid formats allow high cell-densities to be efficiently engineered into tissue structures closely resembling the native tissues. In this work, we explore the assembly capacity of cartilaginous spheroids (d~150 µm) in the context of endochondral bone forma...

The use of multimodal contrast agents can potentially overcome the intrinsic limitations of individual imaging methods. We have validated synthetic antiferromagnetic nanoparticles (SAF-NPs) as bimodal contrast agents for in vitro cell labeling and in vivo cell tracking using magnetic resonance imaging (MRI) and computed tomography (CT). SAF-NP-labe...

Antibodies (Abs) are among the most important class of biologicals, showcasing a high therapeutic and diagnostic value. In the global therapeutic Ab market, fully-human monoclonal Abs (FH-mAbs) are flourishing thanks to their low immunogenicity and high specificity. The rapidly emerging field of single-cell technologies has paved the way to efficie...

Testing multiple biomarkers, as opposed to one, has become a preferred approach for diagnosing many heterogeneous diseases, such as cancer and infectious diseases. However, numerous technologies, including gold standard ELISA and PCR, can detect only one type of biomarker, either protein or nucleic acid (NA), respectively. In this work, we report f...

Rapid diagnostic testing at the site of the patient is essential when a fully equipped laboratory is not accessible. In article number 2008712, Rob Ameloot and co-workers present a novel powder-based 3D-printing method that enables monolithic capillarity-driven microfluidic devices. Precise spatial control over the internal surface chemistry of por...

Microneedle arrays contain needle-like microscopic structures which facilitate drug or vaccine delivery in a minimally invasive way. However, producing hollow microneedles is currently limited by expensive, time consuming and complex microfabrication techniques. In this paper, a novel method to produce hollow polymer microneedles is presented. This...

Duplexed aptamers (DAs) are widespread aptasensor formats that simultaneously recognize and signal the concentration of target molecules. They are composed of an aptamer and aptamer complementary element (ACE) which consists of a short oligonucleotide that partially inhibits the aptamer sequence. Although the design principles to engineer DAs are s...

Rapid diagnostic testing at the site of the patient is essential when a fully equipped laboratory is not accessible. To maximize the impact of this approach, low‐cost, disposable tests that require minimal user‐interference and external equipment are desired. Fluid transport by capillary wicking removes the need for bulky ancillary equipment to act...

Antibody characterization is essential for understanding the immune system and development of diagnostics and therapeutics. Current technologies are mainly focusing on the detection of antigen-specific immunoglobulin G (IgG) using bulk singleplex measurements, which lack information on other isotypes and specificity of individual antibodies. Digita...

Extracellular vesicles (EVs) have drawn huge attention for diagnosing myriad of diseases, including cancer. However, the EV detection and analyses procedures often lack much desired sample standardization. To address this, we used well‐characterized recombinant EVs (rEVs) for the first time as a biological reference material in developing a fiber o...

To date, surface plasmon resonance (SPR) biosensors have been exploited in numerous different contexts while continuously pushing boundaries in terms of improved sensitivity, specificity, portability and reusability. The latter has attracted attention as a viable alternative to disposable biosensors, also offering prospects for rapid screening of b...

Retrieving single cells of interest from an array of microwells for further off-chip analysis is crucial in numerous biological applications. To this end, several single cell manipulation strategies have been developed, including optical tweezers (OT). OT represent a unique approach for contactless cell retrieval, but their performance is often sub...

Autoantibodies are key biomarkers in clinical diagnosis of autoimmune diseases routinely detected by enzyme-linked immunosorbent as-says (ELISA). However, the complexity of these assays is limiting their use in routine diagnostics. Fiber optic-surface plasmon resonance (FO-SPR) can overcome these limitations but improved surface chemistries are sti...

The polymerase chain reaction (PCR) has been the gold standard molecular analysis technique for decades and has seen quite some evolution in terms of reaction components, methodology and readout mechanisms. Nucleic acid enzymes (NAzymes) have been used to further exploit the applications of PCR, but so far the work was limited to the colorimetric G...

Healthcare authorities are calling for new antibacterial therapies to cope with the global emergence of antibiotic-resistant bacteria. Bacteriophage-encoded lysins are a novel class of antibacterials with promising (pre)clinical progress. Custom engineering of lysins allows for the creation of variants against potentially any bacterial pathogen. We...

Nucleic acid enzymes (NAzymes) are nucleic acid molecules with catalytic activity. A subset, the RNA-cleaving NAzyme, is characterized by its substrate of choice: an RNA unit. These enzymes have been used for diverse applications, including biosensor development, akin to their protein counterparts. Owing to their function as both biorecognition ele...

Learning and memory are regulated by neuromodulatory pathways, but the contribution and temporal requirement of most neuromodulators in a learning circuit are unknown. Here we identify the evolutionarily conserved neuromedin U (NMU) neuropeptide family as a regulator of C. elegans gustatory aversive learning. The NMU homolog CAPA-1 and its receptor...

We present a passive heating system that allows controlled and localized on-chip heating, showing a huge potential for point-of-care (POC) diagnostic applications in low-resource settings. By coupling the thermal regulation properties of organic phase change materials (PCMs) to the exothermic crystallization reaction of supercooled sodium acetate t...

Cobalt-nitrilotriacetic acid (Co(III)-NTA) chemistry is a recognized approach for oriented patterning of His6-tagged bioreceptors. We have applied the matching strategy for the first time on an SPR platform, namely the commercialized FO-SPR. To accomplish this, His6-tagged bioreceptor (scFv-33H1F7) and its target PAI-1 were used as a model system,...

When screening microbial populations or consortia for interesting cells, their selective retrieval for further study can be of great interest. To this end, traditional fluorescence activated cell sorting (FACS) and optical tweezers (OT) enabled methods have typically been used. However, the former, although allowing cell sorting, fails to track dyn...

In disease diagnostics, single- and multiplex nucleic acid (NA) detection, with the potential to discriminate mutated strands, is of paramount importance. Current techniques that rely on target amplification or protein-enzyme based signal amplification are highly relevant, yet still plagued by diverse drawbacks including erroneous target amplificat...

The interaction between a bioreceptor and its target is key in developing sensitive, specific and robust diagnostic devices. Suboptimal interbioreceptor distances and bioreceptor orientation on the sensor surface, resulting from uncontrolled deposition, impede biomolecular interactions and lead to a decreased biosensor performance. In this work we...

Inspired by the rapid progress and existing limitations in surface plasmon resonance (SPR) biosensing technology, we have summarized the recent trends in the fields of both chip-SPR and fiber optic (FO)-SPR biosensors during the past five years, primarily regarding smart layers design, multiplexing, continuous monitoring and in vivo sensing. Versat...

The ability to detect low concentrations of protein biomarkers is crucial for the early-stage detection of many diseases, and therefore indispensable for improving diagnostic devices for healthcare. Here, we demonstrate that by integrating DNA nanotechnologies like DNA origami and aptamers we can design innovative biosensing concepts for reproducib...

Learning and memory are regulated by neuromodulatory pathways, but the contribution and temporal requirement of most neuromodulators in a learning circuit are unknown. Here we identify the evolutionarily conserved neuromedin U (NMU) neuropeptide family as a regulator of memory retrieval in C. elegans gustatory aversive learning. The NMU homolog CAP...