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 via 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.
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.
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.
Hybrid Volatolomics and Disease Detection Broza, Yoav Y.; Mochalski, Pawel; Ruzsanyi, Vera ...
Angewandte Chemie (International ed.),
September 14, 2015, Volume:
54, Issue:
38
Journal Article
Peer reviewed
This Review presents a concise, but not exhaustive, didactic overview of some of the main concepts and approaches related to “volatolomics”—an emerging frontier for fast, risk‐free, and potentially ...inexpensive diagnostics. It attempts to review the source and characteristics of volatolomics through the so‐called volatile organic compounds (VOCs) emanating from cells and their microenvironment. It also reviews the existence of VOCs in several bodily fluids, including the cellular environment, blood, breath, skin, feces, urine, and saliva. Finally, the usefulness of volatolomics for diagnosis from a single bodily fluid, as well as ways to improve these diagnostic aspects by “hybrid” approaches that combine VOC profiles collected from two or more bodily fluids, will be discussed. The perspectives of this approach in developing the field of diagnostics to a new level are highlighted.
Ill‐gotten gains: Volatolomes enable identification of the collection of volatile organic compounds in a biological cell, tissue, or organism that are the by‐/end products of cellular processes in the living organism. The new analytical approach of volatolomics allows the large‐scale scientific study of chemical processes involving volatile organic compounds.
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