Recently breath analysis has attracted a lot of attention for disease monitoring and clinical diagnostics as spectrometric techniques of high sophistication and novel sensing materials become ...available. Here advances in these technologies in connection to breath analysis are critically reviewed. A number of breath markers or tracer compounds are summarized and related to different diseases, either for diagnostics or for monitoring. Emphasis is placed on chemo-resistive gas sensors for their low cost and portability highlighting their potential and challenges for breath analysis as they start to be used in studies involving humans.
Nature employs a variety of tactics to precisely time and execute the processes and mechanics of life, relying on sequential sense and response cascades to transduce signaling events over multiple ...length and time scales. Many of these tactics, such as the activation of a zymogen, involve the direct manipulation of a material by a stimulus. Similarly, effective therapeutics and diagnostics require the selective and efficient homing of material to specific tissues and biomolecular targets with appropriate temporal resolution. These systems must also avoid undesirable or toxic side effects and evade unwanted removal by endogenous clearing mechanisms. Nanoscale delivery vehicles have been developed to package materials with the hope of delivering them to select locations with rates of accumulation and clearance governed by an interplay between the carrier and its cargo. Many modern approaches to drug delivery have taken inspiration from natural activatable materials like zymogens, membrane proteins, and metabolites, whereby stimuli initiate transformations that are required for cargo release, prodrug activation, or selective transport. This Perspective describes key advances in the field of stimuli-responsive nanomaterials while highlighting some of the many challenges faced and opportunities for development. Major hurdles include the increasing need for powerful new tools and strategies for characterizing the dynamics, morphology, and behavior of advanced delivery systems in situ and the perennial problem of identifying truly specific and useful physical or molecular biomarkers that allow a material to autonomously distinguish diseased from normal tissue.
Dipstick and lateral-flow formats have dominated rapid diagnostics over the last three decades. These formats gained popularity in the consumer markets due to their compactness, portability and ...facile interpretation without external instrumentation. However, lack of quantitation in measurements has challenged the demand of existing assay formats in consumer markets. Recently, paper-based microfluidics has emerged as a multiplexable point-of-care platform which might transcend the capabilities of existing assays in resource-limited settings. However, paper-based microfluidics can enable fluid handling and quantitative analysis for potential applications in healthcare, veterinary medicine, environmental monitoring and food safety. Currently, in its early development stages, paper-based microfluidics is considered a low-cost, lightweight, and disposable technology. The aim of this review is to discuss: (1) fabrication of paper-based microfluidic devices, (2) functionalisation of microfluidic components to increase the capabilities and the performance, (3) introduction of existing detection techniques to the paper platform and (4) exploration of extracting quantitative readouts
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handheld devices and camera phones. Additionally, this review includes challenges to scaling up, commercialisation and regulatory issues. The factors which limit paper-based microfluidic devices to become real world products and future directions are also identified.
The review covers paper-based microfluidic devices from concept to market by evaluating the feasibility and identifying their impact.
Microfluidics, a technology characterized by the engineered manipulation of fluids at the submillimetre scale, has shown considerable promise for improving diagnostics and biology research. Certain ...properties of microfluidic technologies, such as rapid sample processing and the precise control of fluids in an assay, have made them attractive candidates to replace traditional experimental approaches. Here we analyse the progress made by lab-on-a-chip microtechnologies in recent years, and discuss the clinical and research areas in which they have made the greatest impact. We also suggest directions that biologists, engineers and clinicians can take to help this technology live up to its potential.
Soft rot Enterobacteriaceae(SRE) are bacterial plant pathogens that cause blackleg, wilt and soft rot diseases on a broad range of important crop and ornamental plants worldwide. These organisms ...(spanning the genera Erwinia, Pectobacterium, Dickeya, and Pantoea) cause significant economic and yield losses in the field, and in storage. They are transmissible through surface water, by trade and other movement of plant material and soil, and in some cases are subject to international legislative and quarantine restrictions. Effective detection and diagnosis in support of food security legislation and epidemiology is dependent on the ability to classify pathogenic isolates precisely. Diagnostics and classification are made more difficult by the influence of horizontal gene transfer on phenotype, and historically complex and sometimes inaccurate nomenclatural and taxonomic assignments that persist in strain collections and online sequence databases. Here, we briefly discuss the relationship between taxonomy, genotype and phenotype in the SRE, and their implications for diagnostic testing and legislation. We present novel whole-genome classifications of the SRE, illustrating inconsistencies between the established taxonomies and evidence from completely sequenced isolates. We conclude with a perspective on the future impact of widespread whole-genome sequencing and classification methods on detection and identification of bacterial plant pathogens in support of legislative and policy efforts in food security.
Hydrogels are hydrophilic, highly water swellable polymer networks capable of converting chemical energy into mechanical energy and vice versa. They can be tailored regarding their chemical nature ...and physical structure, sensitiveness to external stimuli and biocompatibility; they can be formed in various structures and integrated into (micro-)systems. Accordingly, over the last decade, these materials have gained considerable recognition as valuable tool for sensors and in diagnostics. This article reviews the use of hydrogels in sensor development with focus on recent efforts in the application of stimuli responsive hydrogels as sensors, hydrogels as suitable matrices in which the sensing (bio-)molecules are embedded and hydrogels for modification and protection of sensor surfaces. In the first part of the review, both sensors and hydrogels are defined and a basic theoretical overview of hydrogels and their behavior is given. Subsequent chapters focus on hydrogels in physicochemical and biochemical sensing mechanisms with a primary emphasis on the hydrogels as such and the applied sensing mechanism. Finally, the review is concluded by a summary and discussion including an outlook on future perspectives for hydrogels in sensing applications.
Lectins possess unique binding properties and are of particular value in molecular recognition. However, lectins suffer from several disadvantages, such as being hard to prepare and showing poor ...storage stability. Boronate‐affinity glycan‐oriented surface imprinting was developed as a new strategy for the preparation of lectin‐like molecularly imprinted polymers (MIPs). The prepared MIPs could specifically recognize an intact glycoprotein and its characteristic fragments, even within a complex sample matrix. Glycan‐imprinted MIPs could thus prove to be powerful tools for important applications such as proteomics, glycomics, and diagnostics.
Sweet‐test thing: Boronate‐affinity glycan‐oriented surface imprinting was used to prepare molecularly imprinted polymers (MIPs) with lectin‐like binding properties. As a proof of principle, glycan‐imprinted magnetic nanoparticles (MNPs) that enable the recognition of an intact glycoprotein and its characteristic fragments through binding to the attached glycans were prepared.
Enzymes underpin physiological function and exhibit dysregulation in many disease-associated microenvironments and aberrant cell processes. Exploiting altered enzyme activity and expression for ...diagnostics, drug targeting, and drug release is tremendously promising. When combined with booming research in nanobiotechnology, enzyme-responsive nanomaterials used for controlled drug release have achieved significant development and have been studied as an important class of drug delivery strategies in nanomedicine. In this review, we describe enzymes such as proteases, phospholipases and oxidoreductases that serve as delivery triggers. Subsequently, we explore recently developed enzyme-responsive nanomaterials with versatile applications for extracellular and intracellular drug delivery. We conclude by discussing future opportunities and challenges in this area.
This review surveys recent advances in controlled drug delivery using emerging nanomaterials that can be triggered by a variety of enzymes.
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