scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Clinically oriented Alzheimer's biosensors: expanding the horizons towards point-of-care diagnostics and beyond

03 Jun 2021-RSC Advances (The Royal Society of Chemistry)-Vol. 11, Iss: 33, pp 20403-20422
TL;DR: Various types of biosensors, which include electrochemical, fluorescent, plasmonic, photoelectrochemical, and field-effect transistor (FET)-based sensor configurations, with better clinical applicability and analytical performance towards AD are highlighted.
Abstract: The development of minimally invasive and easy-to-use sensor devices is of current interest for ultrasensitive detection and signal recognition of Alzheimer's disease (AD) biomarkers. Over the years, tremendous effort has been made on diagnostic platforms specifically targeting neurological markers for AD in order to replace the conventional, laborious, and invasive sampling-based approaches. However, the sophistication of analytical outcomes, marker inaccessibility, and material validity strongly limit the current strategies towards effectively predicting AD. Recently, with the promising progress in biosensor technology, the realization of a clinically applicable sensing platform has become a potential option to enable early diagnosis of AD and other neurodegenerative diseases. In this review, various types of biosensors, which include electrochemical, fluorescent, plasmonic, photoelectrochemical, and field-effect transistor (FET)-based sensor configurations, with better clinical applicability and analytical performance towards AD are highlighted. Moreover, the feasibility of these sensors to achieve point-of-care (POC) diagnosis is also discussed. Furthermore, by grafting nanoscale materials into biosensor architecture, the remarkable enhancement in durability, functionality, and analytical outcome of sensor devices is presented. Finally, future perspectives on further translational and commercialization pathways of clinically driven biosensor devices for AD are discussed and summarized.

Content maybe subject to copyright    Report

Citations
More filters
Journal ArticleDOI
TL;DR: In this article, a plasmonic gold nanoisland (AuNIF) was fabricated onto a glass substrate by a facile seed-mediated growth approach, and the structure of the tortuous gold NIs of the AuNIF was demonstrated by scanning electron microscopy and energy-dispersive X-ray spectroscopy.
Abstract: Plasmonic nanomaterials have been intensively explored for applications in biomedical detection and therapy for human sustainability. Herein, plasmonic gold nanoisland (NI) film (AuNIF) was fabricated onto a glass substrate by a facile seed-mediated growth approach. The structure of the tortuous gold NIs of the AuNIF was demonstrated by scanning electron microscopy and energy-dispersive X-ray spectroscopy. Based on the ultraviolet-visible spectrum, the AuNIF revealed plasmonic absorption with maximum intensity at 624 nm. With the change to the surface topography created by the NIs, the capture efficiency of Escherichia coli (E. coli) by the AuNIF was significantly increased compared to that of the glass substrate. The AuNIF was applied as a surface-enhanced Raman scattering (SERS) substrate to enhance the Raman signal of E. coli. Moreover, the plasmonic AuNIF exhibited a superior photothermal effect under irradiation with simulated AM1.5 sunlight. For photothermal therapy, the AuNIF also displayed outstanding efficiency in the photothermal killing of E. coli. Using a combination of SERS detection and photothermal therapy, the AuNIF could be a promising platform for bacterial theranostics.

9 citations

Journal ArticleDOI
TL;DR: In this article , the authors discuss the latest advances in the applications of metal-organic frameworks (MOFs) for the early diagnosis of Alzheimer's disease via fluorescence and electrochemiluminescence (ECL) detection of AD biomarkers, fluorescence detection of the main metal ions in the brain (Zn2+, Cu2+, Mn2+, Fe3+, and Al3+) in addition to magnetic resonance imaging (MRI) of the Aβ plaques.

4 citations

Journal ArticleDOI
TL;DR: In this paper , an overview of the dynamics of Aβ42 levels in biological fluids as AD progresses is provided, followed by a detailed description of the design and analytical performance of various electrochemical sensors.
Abstract: Alzheimer's disease (AD) is a progressive neurodegenerative disorder with a long latency in the "prodromal" stage, for which there are currently no effective treatments. It is generally accepted that accurate diagnosis and subsequent treatment in the early stages of AD may lead to better therapeutic outcomes. Detection of body fluid biomarkers is an effective strategy for early AD diagnosis. Among them, amyloid β(1–42) (Aβ42), as one of the most important biomarkers of AD, plays a key role in the progression of AD. Currently, electrochemical biosensors offer many advantages in monitoring Aβ42 because they are fast, portable, and capable of on-site analysis. This article provides an overview of the dynamics of Aβ42 levels in biological fluids as AD progresses, followed by a detailed description of the design and analytical performance of various electrochemical sensors. Finally, the challenges of electrochemical sensors for AD diagnosis are discussed, and prospects and trends are outlined.

2 citations

Journal ArticleDOI
TL;DR: In this article , the authors examined the possible effect of Alzheimer's condition on cerebrospinal fluid (CSF) and discussed the latest developed biosensors for the detection of amyloid β and Tau in CSF samples.
Abstract: Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder with an irreversible, progressive, and untreatable nature that causes progressive deterioration, loss of neurons, and cognitive and behavioral decline. An exponential growth of AD is expected in the forthcoming decades. Studies show that amyloid β (Aβ) and Tau proteins are two key biomarkers of AD. Abnormality in Aβ and Tau levels in biofluids - especially cerebrospinal fluid (CSF) - is directly related to AD incidence and progress. Hence, developing sensitive, affordable, and reliable methods for screening and evaluating these biomarker levels is helpful in early diagnosis, tracking, and treatment of AD. This article scrutinizes the possible effect of Alzheimer's condition on CSF. Following a comprehensive summary of biosensors, the latest developed biosensors are discussed for the detection of Aβ and Tau in CSF samples.
Journal ArticleDOI
22 Apr 2023-Sensors
TL;DR: In this paper , the authors examined some of the facts and the current situation of these approaches to AD diagnosis by leveraging the potential of these tools and utilizing the vast amount of non-invasive data in order to revolutionize the early detection of AD according to the principles of a new noninvasive medicine era.
Abstract: Alzheimer’s disease (AD) is now classified as a silent pandemic due to concerning current statistics and future predictions. Despite this, no effective treatment or accurate diagnosis currently exists. The negative impacts of invasive techniques and the failure of clinical trials have prompted a shift in research towards non-invasive treatments. In light of this, there is a growing need for early detection of AD through non-invasive approaches. The abundance of data generated by non-invasive techniques such as blood component monitoring, imaging, wearable sensors, and bio-sensors not only offers a platform for more accurate and reliable bio-marker developments but also significantly reduces patient pain, psychological impact, risk of complications, and cost. Nevertheless, there are challenges concerning the computational analysis of the large quantities of data generated, which can provide crucial information for the early diagnosis of AD. Hence, the integration of artificial intelligence and deep learning is critical to addressing these challenges. This work attempts to examine some of the facts and the current situation of these approaches to AD diagnosis by leveraging the potential of these tools and utilizing the vast amount of non-invasive data in order to revolutionize the early detection of AD according to the principles of a new non-invasive medicine era.
References
More filters
Journal ArticleDOI
19 Jul 2002-Science
TL;DR: It has been more than 10 years since it was first proposed that the neurodegeneration in Alzheimer's disease (AD) may be caused by deposition of amyloid β-peptide in plaques in brain tissue and the rest of the disease process is proposed to result from an imbalance between Aβ production and Aβ clearance.
Abstract: It has been more than 10 years since it was first proposed that the neurodegeneration in Alzheimer9s disease (AD) may be caused by deposition of amyloid β-peptide (Aβ) in plaques in brain tissue. According to the amyloid hypothesis, accumulation of Aβ in the brain is the primary influence driving AD pathogenesis. The rest of the disease process, including formation of neurofibrillary tangles containing tau protein, is proposed to result from an imbalance between Aβ production and Aβ clearance.

12,652 citations

Journal ArticleDOI
17 Aug 2001-Science
TL;DR: The small size and capability of these semiconductor nanowires for sensitive, label-free, real-time detection of a wide range of chemical and biological species could be exploited in array-based screening and in vivo diagnostics.
Abstract: Boron-doped silicon nanowires (SiNWs) were used to create highly sensitive, real-time electrically based sensors for biological and chemical species. Amine- and oxide-functionalized SiNWs exhibit pH-dependent conductance that was linear over a large dynamic range and could be understood in terms of the change in surface charge during protonation and deprotonation. Biotin-modified SiNWs were used to detect streptavidin down to at least a picomolar concentration range. In addition, antigen-functionalized SiNWs show reversible antibody binding and concentration-dependent detection in real time. Lastly, detection of the reversible binding of the metabolic indicator Ca2+ was demonstrated. The small size and capability of these semiconductor nanowires for sensitive, label-free, real-time detection of a wide range of chemical and biological species could be exploited in array-based screening and in vivo diagnostics.

5,841 citations

Journal ArticleDOI
TL;DR: This Position Paper summarises the main outcomes of this international effort to provide the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE).
Abstract: Cerebral small vessel disease (SVD) is a common accompaniment of ageing. Features seen on neuroimaging include recent small subcortical infarcts, lacunes, white matter hyperintensities, perivascular spaces, microbleeds, and brain atrophy. SVD can present as a stroke or cognitive decline, or can have few or no symptoms. SVD frequently coexists with neurodegenerative disease, and can exacerbate cognitive deficits, physical disabilities, and other symptoms of neurodegeneration. Terminology and definitions for imaging the features of SVD vary widely, which is also true for protocols for image acquisition and image analysis. This lack of consistency hampers progress in identifying the contribution of SVD to the pathophysiology and clinical features of common neurodegenerative diseases. We are an international working group from the Centres of Excellence in Neurodegeneration. We completed a structured process to develop definitions and imaging standards for markers and consequences of SVD. We aimed to achieve the following: first, to provide a common advisory about terms and definitions for features visible on MRI; second, to suggest minimum standards for image acquisition and analysis; third, to agree on standards for scientific reporting of changes related to SVD on neuroimaging; and fourth, to review emerging imaging methods for detection and quantification of preclinical manifestations of SVD. Our findings and recommendations apply to research studies, and can be used in the clinical setting to standardise image interpretation, acquisition, and reporting. This Position Paper summarises the main outcomes of this international effort to provide the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE).

3,691 citations

Journal ArticleDOI
Xiangfeng Duan1, Yu Huang1, Yi Cui1, Jianfang Wang1, Charles M. Lieber1 
04 Jan 2001-Nature
TL;DR: The assembly of functional nanoscale devices from indium phosphide nanowires, the electrical properties of which are controlled by selective doping are reported, and electric-field-directed assembly can be used to create highly integrated device arrays from nanowire building blocks.
Abstract: Nanowires and nanotubes carry charge and excitons efficiently, and are therefore potentially ideal building blocks for nanoscale electronics and optoelectronics. Carbon nanotubes have already been exploited in devices such as field-effect and single-electron transistors, but the practical utility of nanotube components for building electronic circuits is limited, as it is not yet possible to selectively grow semiconducting or metallic nanotubes. Here we report the assembly of functional nanoscale devices from indium phosphide nanowires, the electrical properties of which are controlled by selective doping. Gate-voltage-dependent transport measurements demonstrate that the nanowires can be predictably synthesized as either n- or p-type. These doped nanowires function as nanoscale field-effect transistors, and can be assembled into crossed-wire p-n junctions that exhibit rectifying behaviour. Significantly, the p-n junctions emit light strongly and are perhaps the smallest light-emitting diodes that have yet been made. Finally, we show that electric-field-directed assembly can be used to create highly integrated device arrays from nanowire building blocks.

3,280 citations

Journal ArticleDOI
TL;DR: Improvement in the design and construction of electrode systems and their associated electronic instrumentation, together with the commercial development and availability of stable amplifiers and recorders, has now provided entirely satisfactory systems for the rapid and accurate measurement of blood pH, pCO2, and pOz.
Abstract: Instruments capable of continuously indicating the chemical composition of blood have proved to be useful in controlling heart-lung machines, in regulating operative and postoperative management of patients, and in teaching and research. At first, such instruments were used with sensors mounted directly in the extracorporeal blood circuit that is used for perfusion of open-heart surgery patients.] Later, continuous monitoring of both machine and patients was conducted by means of continuous withdrawal of blood pumped into external cuvettes equipped with appropriate sensors. Improvement in the design and construction of electrode systems and their associated electronic instrumentation, together with the commercial development and availability of stable amplifiers and recorders, has now provided entirely satisfactory systems for the rapid and accurate measurement of blood pH, pCO2, and pOz. Electrodes for measurement of blood p 0 2 and $ 0 2 can also be used for recording these tensions in gases. By mixing blood with certain reagents, these electrodes can be used to record blood gas contents as well as tensions. Intravascular electrodes are being used to time hydrogen appearance, to detect changes in oxygen tension, and to record ascorbate indicator dilution curves. Such electrodes are proving valuable in cardiac catheterization and in evaluation of the effectiveness of corrective endocardiac surgical procedures. Speed of response, ease of use, autoclavability, smallness of size, and the practicability of using multiple electrodes simultaneously is often sufficient advantage to overcome the present lack of quantitative response of these relatively simple electrodes. By withdrawing blood through microcatheters, continuous recording of blood composition for many hours, even days, is possible, using only about 10 cc. of blood per hr. Continued development of electrode systems may extend their usefulness to the measurement of blood ions, sugar, and urea and finally result in instruments with which analyses can be performed with a minimum of reagents and with but little delay. Electrode systems readily lend themseIves to either intermittent, semiautomatic, or continuous analytical processes. Blood oxygen tension. Electrodes available at present, mounted in thermostated cuvettes, have proved very satisfactory for the measurement of p 0 2 in blood samples. Thousands of analyses have been performed with the several units available here. We have evaluated several means of utilizing electrodes to follow blood pO2 under conditions encountered in cardiovascular operating rooms and have found that analysis of individual samples, withdrawn in plastic syringes, is the least troublesome and most

3,207 citations