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Scientific Reports Jun 2023Pollution by nanoplastic is a growing environmental and health concern. Currently the extent of nanoplastic in the environment can only be cumbersomely and indirectly...
Pollution by nanoplastic is a growing environmental and health concern. Currently the extent of nanoplastic in the environment can only be cumbersomely and indirectly estimated but not measured. To be able to quantify the extent of the problem, detection methods that can identify nanoplastic particles that are smaller than 1 [Formula: see text]m are critically needed. Here, we employ surface-enhanced Raman scattering (SERS) to image and identify single nanoplastic particles down to 100 nm in size. We can differentiate between single particles and agglomerates and our method allows an improvement in detection speed of [Formula: see text] compared to state-of-the art surface-enhanced Raman imaging. Being able to resolve single particles allows to measure the SERS enhancement factor on individual nanoplastic particles instead of averaging over a concentration without spatial information. Our results thus contribute to the better understanding and employment of SERS for nanoplastic detection and present an important step for the development of future sensors.
Topics: Microplastics; Spectrum Analysis, Raman
PubMed: 37355695
DOI: 10.1038/s41598-023-37290-y -
Analytical Chemistry Dec 2021Biofluid analysis by optical spectroscopy techniques is attracting considerable interest due to its potential to revolutionize diagnostics and precision medicine,...
Biofluid analysis by optical spectroscopy techniques is attracting considerable interest due to its potential to revolutionize diagnostics and precision medicine, particularly for neurodegenerative diseases. However, the lack of effective biomarkers combined with the unaccomplished identification of convenient biofluids has drastically hampered optical advancements in clinical diagnosis and monitoring of neurodegenerative disorders. Here, we show that vibrational spectroscopy applied to human tears opens a new route, offering a non-invasive, label-free identification of a devastating disease such as amyotrophic lateral sclerosis (ALS). Our proposed approach has been validated using two widespread techniques, namely, Fourier transform infrared (FTIR) and Raman microspectroscopies. In conjunction with multivariate analysis, this vibrational approach made it possible to discriminate between tears from ALS patients and healthy controls (HCs) with high specificity (∼97% and ∼100% for FTIR and Raman spectroscopy, respectively) and sensitivity (∼88% and ∼100% for FTIR and Raman spectroscopy, respectively). Additionally, the investigation of tears allowed us to disclose ALS spectroscopic markers related to protein and lipid alterations, as well as to a reduction of the phenylalanine level, in comparison with HCs. Our findings show that vibrational spectroscopy is a new potential ALS diagnostic approach and indicate that tears are a reliable and non-invasive source of ALS biomarkers.
Topics: Amyotrophic Lateral Sclerosis; Biomarkers; Humans; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Tears; Vibration
PubMed: 34905686
DOI: 10.1021/acs.analchem.1c02546 -
Poultry Science Oct 2023The culling of day-old male chicks has caused ethical and economic concerns. Traditional approaches for detecting the in ovo sex of chicken embryos involve opening the... (Review)
Review
The culling of day-old male chicks has caused ethical and economic concerns. Traditional approaches for detecting the in ovo sex of chicken embryos involve opening the eggshell and inner membrane, which are destructive, time-consuming, and inefficient. Therefore, noncontact optical sensing techniques have been examined for the in ovo sexing of chicken embryos. Compared with traditional methods, optical sensing can increase determination throughput and frequency for the rapid sexing of chicken embryos. This paper presented a comprehensive review of the different optical sensing techniques used for the in ovo sexing of chicken embryos, including visible and near-infrared (Vis-NIR) spectroscopy, hyperspectral imaging, Raman spectroscopy, fluorescence spectroscopy, and machine vision, discussing their advantages and disadvantages. In addition, the latest research regarding different detection algorithms and models for the in ovo sexing of chicken embryos was summarized. Therefore, this paper provides updated information regarding the optical sensing techniques that can be used in the poultry industry and related research.
Topics: Chick Embryo; Animals; Male; Chickens; Sex Determination Analysis; Ovum; Spectrum Analysis, Raman; Spectroscopy, Near-Infrared
PubMed: 37480656
DOI: 10.1016/j.psj.2023.102906 -
Journal of Biomedical Optics Dec 2023Measuring hemodynamic function is crucial for health assessment. Optical signals provide relative hemoglobin concentration changes, but absolute measurements require...
SIGNIFICANCE
Measuring hemodynamic function is crucial for health assessment. Optical signals provide relative hemoglobin concentration changes, but absolute measurements require costly, bulky technology. Speckleplethysmography (SPG) uses coherent light to detect speckle fluctuations. Combining SPG with multispectral measurements may provide important physiological information on blood flow and absolute hemoglobin concentration.
AIM
To develop an affordable optical technology to measure tissue absorption, scattering, hemoglobin concentrations, tissue oxygen saturation (), and blood flow.
APPROACH
We integrated reflectance spectroscopy and laser speckle imaging to create coherent spatial imaging (CSI). CSI was validated against spatial frequency domain imaging (SFDI) using phantom-based measurements. arterial and venous occlusion experiments compared CSI with diffuse optical spectroscopy/diffuse correlation spectroscopy (DOS/DCS) measurements.
RESULTS
CSI and SFDI agreed on tissue absorption and scattering in phantom tests. CSI and DOS/DCS showed similar trends and agreement in arterial occlusion results. During venous occlusion, both uncorrected and corrected blood flow decreased with increasing pressure, with an difference in overall blood flow decrease between the methods. CSI and DOS/DCS data showed expected hemoglobin concentrations, , and blood flow trends.
CONCLUSIONS
CSI provides affordable and comprehensive hemodynamic information. It can potentially detect dysfunction and improve measurements, such as blood pressure, , and metabolism.
Topics: Humans; Diagnostic Imaging; Spectrum Analysis; Hemodynamics; Vascular Diseases; Hemoglobins
PubMed: 38116026
DOI: 10.1117/1.JBO.28.12.127001 -
Journal of Food and Drug Analysis Jun 2023Combination of piperaquine (PQ) (320mg) and dihydroartemisinin (DHA) (40 mg) is an anti-malarial formulation, which is recommended by World Health Organization (WHO)....
Combination of piperaquine (PQ) (320mg) and dihydroartemisinin (DHA) (40 mg) is an anti-malarial formulation, which is recommended by World Health Organization (WHO). Simultaneous analysis of PQ and DHA can be problematic due to the lack of chromophores or fluorophores in DHA molecule. Whereas PQ possesses strong UV absorption and it presents in 8 times of DHA contents in the formulation. In this study, two spectroscopic methods, Fourier transform infrared (FTIR) and Raman spectroscopy, were developed for the determination of both drugs in combined tablets. The FTIR and Raman spectra were recorded in the attenuate total reflectance (ATR) and scattering modes, respectively. The original and pretreated spectra from FTIR and handheld-Raman were subjected to Unscrambler® program to construct partial least squares regression (PLSR) model comparing with references values obtained from high performance liquid chromatography (HPLC)-UV method. The optimal PLSR models of PQ and DHA from FTIR spectroscopy were obtained from orthogonal signal correction (OSC) pretreatment at the wavenumbers 400-1,800 cm and 1,400-4,000 cm, respectively. For Raman spectroscopy of PQ and DHA, the optimal PLSR models were obtained from standard normal variate (SNV) pretreatment at the wavenumbers 1,200-2,300 cm and OSC pretreatment at the wavenumber 400-2,300 cm, respectively. Determination of PQ and DHA in tablets from the optimum model was compared with HPLC-UV method. Results were not significantly different at 95% confidence limit (p-value >0.05). The chemometrics-assisted spectroscopic methods were fast (1-3 min), economical and less labor intensive. Moreover, the handheld Raman spectrometer is portable and can be utilized for onsite analysis to facilitate the detection of counterfeit or substandard drugs at ports of entry.
Topics: Antimalarials; Chemometrics; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Tablets
PubMed: 37335160
DOI: 10.38212/2224-6614.3449 -
Analytical and Bioanalytical Chemistry Jan 2022In this work, a novel standardization strategy for quantitative elemental bioimaging is evaluated. More specifically, multi-element quantification by laser...
In this work, a novel standardization strategy for quantitative elemental bioimaging is evaluated. More specifically, multi-element quantification by laser ablation-inductively coupled plasma-time-of-flight mass spectrometry (LA-ICP-TOFMS) is performed by multi-point calibration using gelatin-based micro-droplet standards and validated using in-house produced reference materials. Fully automated deposition of micro-droplets by micro-spotting ensured precise standard volumes of 400 ± 5 pL resulting in droplet sizes of around 200 μm in diameter. The small dimensions of the micro-droplet standards and the use of a low-dispersion laser ablation setup reduced the analysis time required for calibration by LA-ICPMS significantly. Therefore, as a key advance, high-throughput analysis (pixel acquisition rates of more than 200 Hz) enabled to establish imaging measurement sequences with quality control- and standardization samples comparable to solution-based quantification exercises by ICP-MS. Analytical figures of merit such as limit of detection, precision, and accuracy of the calibration approach were assessed for platinum and for elements with biological key functions from the lower mass range (phosphorus, copper, and zinc). As a proof-of-concept application, the tool-set was employed to investigate the accumulation of metal-based anticancer drugs in multicellular tumor spheroid models at clinically relevant concentrations. Graphical abstract.
Topics: Calibration; Laser Therapy; Mass Spectrometry; Platinum; Spectrum Analysis
PubMed: 33954828
DOI: 10.1007/s00216-021-03357-w -
The Analyst Oct 2021Clinical medicine continues to seek novel rapid non-invasive tools capable of providing greater insight into disease progression and management. Raman scattering based... (Review)
Review
Clinical medicine continues to seek novel rapid non-invasive tools capable of providing greater insight into disease progression and management. Raman scattering based technologies constitute a set of tools under continuing development to address outstanding challenges spanning diagnostic medicine, surgical guidance, therapeutic monitoring, and histopathology. Here we review the mechanisms and clinical applications of Raman scattering, specifically focusing on high-speed imaging methods that can provide spatial context for translational biomedical applications.
Topics: Spectrum Analysis, Raman
PubMed: 34596653
DOI: 10.1039/d1an00954k -
Fa Yi Xue Za Zhi Oct 2022Hyperspectral imaging technology can obtain the spatial and spectral three-dimensional imaging of substances simultaneously, and obtain the unique continuous...
Hyperspectral imaging technology can obtain the spatial and spectral three-dimensional imaging of substances simultaneously, and obtain the unique continuous characteristic spectrum of substances in a wide spectrum range at a certain spatial resolution, which has outstanding advantages in the fine classification and identification of biological substances. With the development of hyperspectral imaging technology, a large amount of data has been accumulated in the exploration of data acquisition, image processing and material inspection. As a new technology means, hyperspectral imaging technology has its unique advantages and wide application prospects. It can be combined with the common biological physical evidence of blood (stains), saliva, semen, sweat, hair, nails, bones, etc., to achieve rapid separation, inspection and identification of substances. This paper introduces the basic theory of hyperspectral imaging technology and its application in common biological evidence examination research and analyzes the feasibility and development of biological evidence testing and identification, in order to provide a theoretical basis for the development of new technology and promote hyperspectral imaging technology in related biological examination, to better serve the forensic practice.
Topics: Spectrum Analysis; Hyperspectral Imaging; Forensic Medicine; Blood Stains; Technology
PubMed: 36727181
DOI: 10.12116/j.issn.1004-5619.2021.510904 -
Molecules (Basel, Switzerland) Sep 2020Fish and other seafood products have a limited shelf life due to favorable conditions for microbial growth and enzymatic alterations. Various preservation and/or... (Review)
Review
Fish and other seafood products have a limited shelf life due to favorable conditions for microbial growth and enzymatic alterations. Various preservation and/or processing methods have been developed for shelf-life extension and for maintaining the quality of such highly perishable products. Freezing and frozen storage are among the most commonly applied techniques for this purpose. However, frozen-thawed fish or meat are less preferred by consumers; thus, labeling thawed products as fresh is considered a fraudulent practice. To detect this kind of fraud, several techniques and approaches (e.g., enzymatic, histological) have been commonly employed. While these methods have proven successful, they are not without limitations. In recent years, different emerging methods have been investigated to be used in place of other traditional detection methods of thawed products. In this context, spectroscopic techniques have received considerable attention due to their potential as being rapid and non-destructive analytical tools. This review paper aims to summarize studies that investigated the potential of emerging techniques, particularly those based on spectroscopy in combination with chemometric tools, to detect frozen-thawed muscle foods.
Topics: Animals; Freezing; Humans; Imaging, Three-Dimensional; Seafood; Spectrum Analysis
PubMed: 33003382
DOI: 10.3390/molecules25194472 -
Cells Sep 2021Data volumes collected in many scientific fields have long exceeded the capacity of human comprehension. This is especially true in biomedical research where multiple...
Data volumes collected in many scientific fields have long exceeded the capacity of human comprehension. This is especially true in biomedical research where multiple replicates and techniques are required to conduct reliable studies. Ever-increasing data rates from new instruments compound our dependence on statistics to make sense of the numbers. The currently available data analysis tools lack user-friendliness, various capabilities or ease of access. Problem-specific software or scripts freely available in supplementary materials or research lab websites are often highly specialized, no longer functional, or simply too hard to use. Commercial software limits access and reproducibility, and is often unable to follow quickly changing, cutting-edge research demands. Finally, as machine learning techniques penetrate data analysis pipelines of the natural sciences, we see the growing demand for user-friendly and flexible tools to fuse machine learning with spectroscopy datasets. In our opinion, open-source software with strong community engagement is the way forward. To counter these problems, we develop Quasar, an open-source and user-friendly software, as a solution to these challenges. Here, we present case studies to highlight some Quasar features analyzing infrared spectroscopy data using various machine learning techniques.
Topics: Humans; Machine Learning; Reproducibility of Results; Software; Spectrum Analysis
PubMed: 34571947
DOI: 10.3390/cells10092300