Analytical chemistry uses methods and instrumentation to investigate chemical and biological systems. It is often used to maintain quality control and assurance in various branches of science. Some of its applications are found in the pharmaceutical drug manufacturing process.
In medicine, analytical chemistry helps physicians diagnose and understand diseases and analyze biological samples such as enzymes, bacteria, and blood. Analytical chemistry uses instrumentation, wet chemistry methods, and statistics to understand certain medical samples and diseases, which also aids in medical research and pharmaceutical development.
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What is analytical chemistry?
Analytical chemistry uses instruments and methods to separate, detect and quantify matter. Separation techniques isolate molecules. Qualification techniques are used to identify analytes, while quantitative techniques determine concentration levels. Common instrumental methods used for separation include chromatography, electrophoresis, or field-flow fractionation.
Quantifying the analyte can be done using either the same instrument after separation or using spectroscopic methods for further characterization and analysis. Often the classical instrumental methods use the same instrument to separate, isolate and quantify samples.
However, spectroscopic instrumentation is often also used due to its advantage of differentiating molecules that have co-elution times in chromatography. Moreover, statistics are used in combination with these techniques to further characterize the structure and detect key components.
Analytical techniques in medicine
There are many applications of using analytical techniques in various fields of medicine to help characterize diseases with a view of developing rapid diagnostic techniques. Several analytical approaches allow for tracking metabolic pathways to monitor the efficacy of therapeutic treatments and their impact on the body. Some non-invasive methodologies use biomarkers in saliva and breath to identify certain diseases and disorders.
Hence, rapid diagnostic methods such as colorimetric assays and targeted metabolite breathalyzer as well as saliva swab technologies can be developed. Additionally, using biomarkers for detecting disease allows for many rapid test kits for disease diagnosis being used for the clinic to detect diseases early for early intervention.
Saliva is a good sample to use for developing diagnostic instruments because it is non-invasive to collect samples. Saliva is secreted from hundreds of glands located within the mouth. There are over 800 metabolites identified in saliva, ranging from carboxylic acids and steroids to quaternary ammonium salts and polyketides.
For this reason, saliva has been accepted in the medical field as an important diagnostic fluid, similar to urine and blood. It is important to have sensitive detection methods to measure variations in saliva to correlate it with other biofluids. Additionally, analytical techniques can be used on saliva samples to monitor immune responses to infection, analyze pharmaceutical drug levels in the body, and detection of illegal drugs.
The passive drool technique is one of the most widely used methods for saliva sampling. It involves the saliva pooling on the mouth floor, which is then collected in a cryovial by tilting the head. This is a very cost-effective method. Alternatively, oral swabs are used.
Another non-invasive sample type used for medical diagnostic devices involves exhaled breath. One consideration around using the breath as a sample is the diffusion of volatile organic compounds (VOCs) from blood to alveolar air. In addition, special care is needed to ensure that the sample quality is maximized by minimizing the interferences environmental VOCs or ones that do not originate from the source. Multiple analytical techniques have been developed using the breath as a sample. However, there are still issues involving sensitivity and accuracy.
Another common non-invasive biological fluid used for biomedical diagnostics in clinical settings is sweat. Sweat biomarkers can be used in analytical devices such as in a transdermal patch. Typically, the patch can monitor infections based on unique biomarkers present that relate to specific diseases and infections. Hence, analytical chemistry techniques are commonly used in medicine for rapid diagnostic methods to help quickly diagnose disease and infection to enable early intervention.
Analytical chemist, healthcare
Sources:
- R. Valagaleti, P.K. Burns, Michael Gill.; Drug Inform. J., 37 (2003), pp. 407-438.
- Skoog, Douglas A.; West, Donald M.; Holler, F. James; Crouch, Stanley R. (2014). Fundamentals of Analytical Chemistry. Belmont: Brooks/Cole, Cengage Learning. p. 1.
- Barnes V.M., Kennedy A.D., Panagakos F., Devizio W., Trivedi H.M., Jönsson T., Guo L., Cervi S., Scannapieco F.A. Global Metabolomic Analysis of Human Saliva and Plasma from Healthy and Diabetic Subjects, with and without Periodontal Disease. PLoS ONE. 2014;9
- Berna A.Z., McCarthy J.S., Wang R.X., Saliba K.J., Bravo F.G., Cassells J., Padovan B., Trowell S.C. Analysis of Breath Specimens for Biomarkers of Plasmodium falciparum Infection. J. Infect. Dis. 2015;212:1120–1128.
- Dame Z.T., Aziat F., Mandal R., Krishnamurthy R., Bouatra S., Borzouie S., Guo A.C., Sajed T., Deng L., Lin H., et al. The human saliva metabolome. Metabolomics. 2015;11:1864–1883.
- Cao W.Q., Duan Y.X. Breath analysis: Potential for clinical diagnosis and exposure assessment. Clin. Chem. 2006;52:800–811
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