Trends in Analytical Chemistry最新文献

Clustered, regularly interspaced short palindromic repeats (CRISPR) system exhibits considerable potential in life science and bioengineering due to its exceptional sensitivity and specificity in gene editing and biosensing technology. While substantial efforts have been invested over the past decade in developing versatile CRISPR/Cas biosensing methods, the challenges of translating CRISPR/Cas technology into integrated biosensing devices (especially emerging wearables) for point-of-care (POC) applications persist. This review provides a comprehensive summary of the development of CRISPR/Cas biosensing systems, transitioning from complex lab assays to relatively integrated portable devices supported by novel technologies and advanced platforms (such as lateral flow assay, microfluidics, portable electrochemical biochips, etc.). The intrinsic benefits of various biosensing platforms bolster the CRISPR/Cas system's capacity for high-throughput, multiplexed and automation detection. The article aims to serve as a concise resource, inspiring further combinations of CRISPR/Cas technology with advanced biosensing platforms for POC health monitoring, disease diagnosis and personalized medicine.

During the COVID-19 pandemic, lateral flow assay (LFA) based diagnostics witnessed an unprecedented expansion, enabling testing access beyond the conventional healthcare system. Their appeal lies in their user-friendly nature, affordability, and swift results. However, their impact on disease control is limited by factors like sensitivity and specificity. To address these issues and achieve high accuracy, affordability, PCR-level sensitivity, and rapid detection, significant progress has been made in the development of next-generation lateral flow test strips. This review primarily focuses on dual/multi-modal immunoassay techniques, extensively employed to enhance LFA diagnostic sensitivity. Additionally, we delve into the separate roles of dual and multi-modal readers in ensuring specificity and amplifying signal sensitivity. Finally, the challenges and potential future outlook are thoroughly explored for advancing diagnostic methods.

The characteristics of Plastic Optical Fibers (POFs) are exploited to realize simple, highly sensitive, and low-cost bio/chemical sensors via innovative schemes. The POF's multimode characteristic and the simple modification processes are used to obtain novel ultra-sensitive platforms that can be combined with different kinds of receptors (bio-mimetic or biological receptors) to detect specific substances in different ranges for several application fields. This review reports several POF platforms based on different optical transduction principles obtained via low-cost setups, such as surface plasmon resonance (SPR), localized SPR, lossy mode resonance, evanescent wave, and others. The reported sensor configurations are useful to understand how the balance of the combination of these two components (POF platforms and receptors) can produce the desired optimal performance of the POF-based bio/chemical sensor in terms of substance and detection range.

The chemical composition of exhaled human breath can be strongly correlated to medical conditions such as lung cancer or gastrointestinal diseases. To establish these correlations and, most importantly, to use them in diagnostics, molecular gas detection needs to be performed at trace concentrations, typically at parts-per-million (ppm) levels or below, for many compounds simultaneously. Traditional methods such as gas chromatography, a workhorse in scientific laboratories, is ill-suited for the fast, inexpensive point-of-care diagnostics that would be needed to build statistically meaningful ensembles over large populations. With the increasing availability and decreasing cost of high-power diode lasers and of uncooled CMOS cameras, spontaneous Raman spectroscopy (SRS), a vibrational molecular fingerprinting tool, is emerging as an economic alternative. Although gas SRS scattering cross sections are much smaller than, e.g., Rayleigh scattering cross sections, considerable progress in the development of enhancement techniques has been made over the past decade. This work reviews SRS enhancement approaches in the context of established human breath tests and provides a comparison with alternatives. Already, numerous trace gases such as H₂, CH₄, ¹³CO₂, and volatile organic compounds like acetone can be rapidly quantified in breath at concentrations below 1 ppm with SRS. With improvements in resolution and design of enhancement systems, SRS-based sensors could be scalably deployed in, e.g., pharmacies, and non-invasively screen for dozens of analytes at the parts-per-billion level.

With the continuous expansion of the global population, securing adequate high-quality food suppliers has become paramount. The process of food spoilage not only produces considerable food waste but also has negative effects on the human body.Therefore, developing effective real-time methods for monitoring food freshness is crucial. This article categorizes and discusses the current state of development of optical sensors using natural colorants, small fluorescent probes, and nanosensing materials between 2020 and 2023. The article also reviews the strengths and weaknesses of these detection methodologies and provides a summary of the current research on the fabrication of portable devices. Emerging technologies related to monitoring of food freshness, such as intelligent device-based detection methods, functionally integrated smart packaging, and sensing arrays, are also discussed. Finally, this article highlights the existing research gaps and proposes directions for future research in food-freshness detection.

Laser-induced breakdown spectroscopy (LIBS) is a powerful and versatile analytical tool for real-time, simultaneous, and all-element detection. However, its broader applications are constrained by matrix effects, large signal uncertainty, molecular information absence, and limited mapping analysis. LIBS-based spectral tandem technologies aim to address these limitations by combining LIBS with elemental analytical technologies (laser ablation-inductively coupled plasma mass spectroscopy, X-ray fluorescence, and laser-induced fluorescence spectroscopy), molecular spectroscopy (Raman spectroscopy and near-infrared spectroscopy), and scanning technologies (hyperspectral imaging). Tandem technologies offer complementary advantages over individual LIBS, including comprehensive elemental determination, bridging the gap between elemental and molecular information, and high spatial-resolution elemental mapping. This review focuses on the progress in measurement schemes, data fusion methods, unique synergic results, and future prospects. This work aims to guide analysts to address complex analytical tasks and foster mutually beneficial advancements wherein LIBS and other analytical technologies grow synergistically.

The advancements of chemical sensors over the past 50 years have significantly expanded the diversity of available sensors making them more affordable, portable, sensitive, and partially chemically selective. Despite these advancements, the diversity and capability of sensors used in breath analysis has remained limited due to challenges that persist in this field. This encompasses fluctuations in humidity, temperature, and oxygen concentration within breath that all pose challenges that can significantly affect sensor output. This review article aims to introduce and compare the techniques used in current chemical sensor arrays for breath analysis. A brief overview of the discrete chemical sensors and arrays employed in breath research, at both commercial and research levels, is discussed. Furthermore, current trends in data analysis for chemical sensor arrays in breath analysis is described. Finally, a detailed outlook of recent diagnostic results from studies implementing sensor arrays from the last 5 years is outlined.

Humanity endeavors to resume crewed missions to the Moon and prepares for the exploration of Mars. These missions will require sustained human presence in space for longer periods than ever before. Space exposes astronauts to demanding conditions, including microgravity, radiation, rapid light-dark cycles, and hazardous chemicals. Gas sensors will be pivotal in preserving astronaut health by providing critical health data (e.g., through breath analysis) and space-resolved environmental information. Here, we explore the recent progress of gas sensors to meet the key needs of space exploration. First, the fundamental sensing principles of electrochemical, chemoresistive, mass-sensitive, and optical sensors are briefly introduced. Then, we connect space-related health challenges with suitable breath markers and sensor solutions, encompassing areas like gut microbiome, muscle activity, cardiovascular health, hepatic and renal function, and circadian rhythm. Finally, environmental exposure guidelines and suitable sensor innovations for distributed air quality monitoring in space vehicles and habitats are presented.

Comprehensive characterization of lipidomes is highly desirable for fundamental biological study as well as for disease biomarker screening. As highly complementary to the genomics and proteomics, lipidomics provides important information related to lipidomes and enables their correlations to genomes and proteomes. During the past few years, significant progresses have been made in instrumentation and analytical method for elucidating detailed structural features of lipids. In this review, the current status of the lipidomics with higher structural specificity is surveyed and its capacity as well as existing challenges are discussed in terms of supporting future human lipidome project, which is expected to be the next important step for human omics study.

Although exhaled breath analysis for diagnosing human health is a concept that dates to antiquity, the application of modern analytical and collection techniques to exhaled breath analysis has rapidly evolved the field. Distinct phases of breath, including breath gas, condensate, and aerosols have been defined in the literature. Although traditionally used for clinical diagnostics, breath analysis has significant applications in evaluating occupational and environmental exposures. Breath analysis can reveal exposure compounds and their metabolites as well as biomarkers of oxidative stress and inflammation. As this field grows, new developments in exposure monitoring have implications for informing policy, best practices, and remediation to help reduce occupational and environmental exposures. This review aims to guide prospective research in breath analysis for exposure monitoring by summarizing current techniques and analytes of interest in a variety of occupational and environmental contexts, while highlighting knowledge gaps to be addressed.