Biosensors are valuable tools for the detection of biological species, including cells, pathogens, proteins, and other biological molecules. Biosensing devices integrated with microfluidics not only allow for easier sample preparation, portability, and reduced detection time and cost but also offer unique features such as label-free detection and improved sensitivity. Cardiovascular diseases (CVDs), particularly acute myocardial infarction, which is considered one of the main causes of death, are currently diagnosed by electrocardiography (ECG), which has been proven to be inadequate. To overcome the limitations of ECG, the efficient detection of cardiac biomarkers and specifically the measurement of cardiac troponins (cTnT and cTnI) are suggested. This review aims to expound on microfluidics, the most recent materials to develop these devices, and their application in medical diagnosis, particularly in CVD detection. Moreover, we will explore some of the prevalent and last readout methods to investigate in-depth electrochemical label-free detection methods for CVDs, primarily based on voltammetry and electrochemical impedance spectroscopy, with the main focus on structural details.

Food safety is the prime area of concern that builds trust. With the prevailing advancements, it has become facile to ensure safety in almost all aspects. Technology has grown from tedious lab techniques to modern chromatographic techniques and immunoassays, progressed with more precise and rapid sensing through the advent of Biosensors. Biosensors provide an automated technology by presenting superfast, nondestructive and cost-effective detection in food analysis. SPR biosensor is an optical biosensor known for its versatility and has wider applications in food testing and analysis. It has an optical system for excitation and interrogation of surface plasmons, and a biomolecular recognition element to detect and seize the target analyte present in a sample. The optical signal detects the binding analyte, on the recognition element, which results in a change in refractive index at the surface and modifies the surface plasmons\' propagation constant. SPR aids in label-free detection of various components such as adulterants, antibiotics, biomolecules, genetically modified foods, pesticides, insecticides, herbicides, microorganisms and microbial toxins in food and assures safety. The distinct advancements of SPR in food analysis have been found and discussed. The review also provides knowledge on the advantages and the key challenges encountered by SPR.

Single-cell analysis has gained considerable attention for disease diagnosis, drug screening, and differentiation monitoring. Compared to the well-established flow cytometry, which uses fluorescent-labeled antibodies, microfluidic impedance cytometry (MIC) offers a simple, label-free, and noninvasive method for counting, classifying, and monitoring cells. Superior features including a small footprint, low reagent consumption, and ease of use have also been reported. The MIC device detects changes in the impedance signal caused by cells passing through the sensing/electric field zone, which can extract information regarding the size, shape, and dielectric properties of these cells. According to recent studies, electrode configuration has a remarkable effect on detection accuracy, sensitivity, and throughput. With the improvement in microfabrication technology, various electrode configurations have been reported for improving detection accuracy and throughput. However, the various electrode configurations of MIC devices have not been reviewed. In this review, the theoretical background of the impedance technique for single-cell analysis is introduced. Then, two-dimensional, three-dimensional, and liquid electrode configurations are discussed separately; their sensing mechanisms, fabrication processes, advantages, disadvantages, and applications are also described in detail. Finally, the current limitations and future perspectives of these electrode configurations are summarized. The main aim of this review is to offer a guide for researchers on the ongoing advancement in electrode configuration designs.

Identification of the target proteins of small molecule drugs is crucial for understanding the mechanisms of drug actions and its side effects. Conventional methods require chemical modification, which might alter the activities of the drugs. Various label-free techniques have been developed to identify drug target proteins without chemical modifications. This includes drug affinity responsive target stability (DARTS), stability of proteins from rates of oxidation (SPROX), cellular thermal shift assay (CETSA), thermal proteome profiling (TPP) and many others. Here we review the principles and applications of these label-free techniques, their advantages and limitations, as well as the most recent advances.
鉴定小分子药物的靶蛋白对于理解药物的作用机理以及药物副作用至关重要。传统方法需要对药物进行化学修饰共价交联，可能会导致药物活性的改变。目前已经发展多种无需化学修饰便可以对药物靶蛋白鉴定的方法，包括药物亲和力反应靶标稳定性技术 (Drug affinity responsive target stability，DARTS)、蛋白质氧化速率稳定性技术 (Stability of proteins from rates of oxidation，SPROX)、细胞热移位分析技术 (Cellular thermal shift assay，CETSA) 和热蛋白组分析技术 (Thermal proteome profiling，TPP) 等。文中将介绍这些技术的原理、应用以及各自的优点和局限性，另外也介绍了这些技术最新的优化方案。.

Detection of a single biomolecule, ranging from nucleic acids, proteins, viruses to bacteria, is of paramount importance in various fields including biology, environment, food and agriculture industry, public health, and medicine. With the understanding of the biological functions of these biomolecules (or bioparticles) and their impacts on public health, environmental pollution, and food safety, advanced detection techniques are unprecedentedly demanded for their early and/or sensitive detection. In this critical review, a series of elegant research about digital detection of biomolecules with potential single copy sensitivity is reviewed and summarized with the focus on the design principle and the innovation of how to accomplish the \"digital\" detection concept. Starting with a brief introduction on the importance of digital detection, recent advances in \"digital\" biomolecule detection with single copy sensitivity are grouped and discussed based on the difference of signal reporting systems, including surrogate signal development for \"digital\" detection, direct visualization for \"digital\" detection, and nucleic acid amplification enabled \"digital\" detection. Interdisciplinary combination and integration of different cutting-edge techniques are also discussed with details. The review is closed with the conclusion and future trends.

Surface plasmon resonance imaging (SPRi) has been increasingly used in the label-free detections of various biospecies, such as organic toxins, proteins, and bacteria. In combination with the well-developed microarray immunoassay, SPRi has the advantages of rapid detection in tens of minutes and multiplex detection of different targets with the same biochip. Both prism-based and prism-free configurations of SPRi have been developed for highly integrated portable immunosensors, which have shown great potential on pathogen detection and living cell imaging. This review summarizes the recent advances in immunoassay biosensing with SPRi, with special emphasis on the multiplex detections of foodborne pathogens. Additionally, various spotting techniques, surface modification protocols, and signal amplification methods have been developed to improve the specificity and sensitivity of the SPRi biochip. The challenges in multiplex detections of foodborne pathogens in real-world samples are addressed, and future perspectives of miniaturizing SPRi immunosensors with nanotechnologies are discussed.

Skeletal stem cells (SSC) are a sub-population of bone marrow stromal cells that reside in postnatal bone marrow with osteogenic, chondrogenic and adipogenic differentiation potential. SSCs reside only in the bone marrow and have organisational and regulatory functions in the bone marrow microenvironment and give rise to the haematopoiesis-supportive stroma. Their differentiation capacity is restricted to skeletal lineages and therefore the term SSC should be clearly distinguished from mesenchymal stem cells which are reported to exist in extra-skeletal tissues and, critically, do not contribute to skeletal development. SSCs are responsible for the unique regeneration capacity of bone and offer unlimited potential for application in bone regenerative therapies. A current unmet challenge is the isolation of homogeneous populations of SSCs, in vitro, with homogeneous regeneration and differentiation capacities. Challenges that limit SSC isolation include a) the scarcity of SSCs in bone marrow aspirates, estimated at between 1 in 10-100,000 mononuclear cells; b) the absence of specific markers and thus the phenotypic ambiguity of the SSC and c) the complexity of bone marrow tissue. Microfluidics provides innovative approaches for cell separation based on bio-physical features of single cells. Here we review the physical principles underlying label-free microfluidic sorting techniques and review their capacity for stem cell selection/sorting from complex (heterogeneous) samples.

The detection techniques used in biosensors can be broadly classified into label-based and label-free. Label-based detection relies on the specific properties of labels for detecting a particular target. In contrast, label-free detection is suitable for the target molecules that are not labeled or the screening of analytes which are not easy to tag. Also, more types of label-free biosensors have emerged with developments in biotechnology. The latest developed techniques in label-free biosensors, such as field-effect transistors-based biosensors including carbon nanotube field-effect transistor biosensors, graphene field-effect transistor biosensors and silicon nanowire field-effect transistor biosensors, magnetoelastic biosensors, optical-based biosensors, surface stress-based biosensors and other type of biosensors based on the nanotechnology are discussed. The sensing principles, configurations, sensing performance, applications, advantages and restriction of different label-free based biosensors are considered and discussed in this review. Most concepts included in this survey could certainly be applied to the development of this kind of biosensor in the future.