Raman spectroscopy is an analytical tool that is highly preferred for label-free chemical analysis because it is a non-destructive technique that keeps the specimen safe. Raman spectroscopy is an efficient tool for performing label-free chemical analysis of a variety of biomolecules such as proteins, cell membranes, and other substances. The high chemical specificity of Raman spectroscopy makes it an ideal choice for performing label-free chemical analysis.
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Raman Spectroscopy for Label-Free Monitoring of Drugs
Nano-encapsulated drugs are being researched extensively these days, with researchers utilizing several methods for performing their label-free chemical analysis. The study of mechanisms that regulate the delivery of these drugs in the human body is possible by label-free chemical analysis.
Raman spectroscopy is being utilized for label-free chemical analysis of nano-encapsulated drugs to analyze their intracellular delivery. Label-free chemical analysis of breast cancer cells treated with novel anti-cancer substances encapsulated into nanoparticles is performed by medical researchers for analysis of drug response.
Label-Free Chemical Analysis: An Essential Tool in Cancer Research
The label-free chemical analysis by Raman spectroscopy can also be used to differentiate between the different types of cells. The label-free chemical analysis of a particular cell by using Raman spectroscopy results in a specific chemical footprint. This particular type of label-free chemical analysis by Raman spectroscopy is useful for elevated diagnostic accuracy.
Label-free chemical analysis using Raman spectroscopy is extensively used by cancer researchers to distinguish between different types of acute myeloid leukemia types. The label-free chemical analysis using Raman spectroscopy generates unique Raman spectra corresponding to each type of cancer cell, which can be used to diagnose the type of cancer.
Label-Free Chemical Analysis of Proteins
Among the different methods available for label-free chemical analysis of proteins, surface-enhanced Raman spectroscopy (SERS) is one of the most preferred methods. This surface-enhanced label-free chemical analysis method is a potent technique for the structural analysis of biomolecules in physiological conditions.
A recent article published in the International Journal of Molecular Sciences provides a useful review of the advantage of SERS for label-free chemical analysis of proteins. Label-free chemical analysis by SERS proves valuable for investigating the inherent structural details of proteins and is gaining growing interest in the fields of biophysics, bioanalytical chemistry, and biomedicine.
Cyt-c is a specific type of hemoprotein that is usually analyzed using SERS. Resonance spectroscopy for label-free chemical analysis of Cyt-c is notably effective in the characterization of heme-proteins due to the sensitivity of their vibrational modes, which serve as indicators for the redox state, spin and ligation pattern of the heme-iron.
The use of SERS as a label-free chemical analysis tool for identifying membrane proteins integrated into cellular, virtual, or bacterial walls has encountered challenges related to spectral fluctuations when the target proteins were randomly adsorbed onto SERS-active materials.
To address this issue related to label-free chemical analysis, the functionalization of nanomaterials with specific antibodies proved beneficial for controlled protein capture. Nevertheless, a significant portion of proteins lacking chromophores have limited Raman cross-sections, resulting in relatively weak signals during label-free chemical analysis. Hence, there is a pressing need to develop biocompatible, highly sensitive, and selective SERS-active materials for performing label-free chemical analysis effective in the adhesion of such biological samples.
Label-Free Chemical Analysis of Dairy Products Using Raman Spectroscopy
Raman spectroscopy for label-free chemical analysis offers exceptional sensitivity to detect specific compounds within a product. Pioneering research conducted on butter samples at Teagasc has showcased Raman spectroscopy's capacity to differentiate pasture-derived butter from products produced through indoor feeding systems via label-free chemical analysis.
The application of label-free chemical analysis utilizing Raman spectroscopy in combination with microscopy has empowered Teagasc researchers to map the distribution of micronutrients like carotenoids within dairy emulsions.
This will enable the detection of micronutrients along with assessing the quality of dairy products to ensure the safety of products for human consumption.
Multi-Excitation Raman Spectroscopy: A Novel Label-Free Chemical Analysis Tool for Medical Diagnosis
Present diagnostic techniques for acute and chronic infections are intricate and demand specialized skills. The conventional methods for diagnosing clinical infections are slow, which can cause a delay in treatment and endanger the patient’s life.
Label-free chemical analysis using Raman spectroscopy is an essential diagnostic tool in modern medicine, with researchers developing novel methods to improve the process of label-free chemical analysis. Researchers reported a novel method of Multi-Excitation Raman spectroscopy in Analytical Chemistry, which is an effective method of novel-free chemical analysis for detection of infectious agents.
Multi-excitation Raman spectroscopy-based approach is employed for the label-free chemical analysis and non-invasive identification of microbial pathogens. This method can be directly applied to unprocessed clinical samples, providing prompt data via label-free chemical analysis to aid in diagnosis.
The particular label-free chemical analysis technique operates by differentially exciting non-resonant and resonant molecular components within bacterial cells, thereby enhancing its capacity to fingerprint molecules. This enables this label-free chemical analysis method to achieve strain-level differentiation among bacterial species.
The researchers used label-free chemical analysis Multi-excitation Raman spectroscopic technique for the detection of Pseudomonas aeruginosa and Staphylococcus aureus. The specimens were analyzed individually in separation and sputum media.
With the integration of label-free chemical analysis data by multi-excitation Raman spectra with multivariate analysis, the accuracy rate reached an impressive 99.75% for both species, encompassing all strains. Notably, the novel method of label-free chemical analysis achieved 100% accuracy in distinguishing between drug-sensitive and drug-resistant S. aureus.
Raman Spectroscopy has proved to be an essential technique for label-free chemical analysis in the fields of food sciences, biosciences, and the medical industry. The application of modern Industry 4.0 advancements, such as the implementation of Machine Learning (ML) tools, will enable faster data processing for effective label-free chemical analysis.
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References and Further Reading
Laboratoy of Nanomedicine and Clinical Biophotonics, (2023). Raman Spectroscopy For Label Free Cells Analysis. [Online]
Available at: https://www.labion.eu/expertise-2/raman-spectroscopy-for-label-free-cells-analysis/#:~:text=Thanks%20to%20both%20the%20high,the%20use%20of%20specific%20antibodies.
TEAGASC, (2021). Raman Spectroscopy to Assess Nutritional Quality in Dairy. [Online]
Available at: https://www.teagasc.ie/media/website/publications/2021/TR_Summer2021_Raman.pdf
Cai L. et. al. (2022). Label-Free Surface-Enhanced Raman Spectroscopic Analysis of Proteins: Advances and Applications. International Journal of Molecular Sciences. 23(22). 13868. Available at: https://doi.org/10.3390/ijms232213868
Lister, A. et. al. (2022). Multi-excitation Raman spectroscopy for label-free, strain-level characterization of bacterial pathogens in artificial sputum media. Analytical Chemistry, 94(2), 669-677. Available at: https://doi.org/10.1021/acs.analchem.1c0250