Biosensores como herramienta microbiologica

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Biosensor as a microbiology tool.
A biosensor is a device in charge of detecting/analyzing chemical substances, which can be
combined with biological or physical-chemical components. It is made up of a biological
element in charge of recognition (cell, tissue, enzyme, etc.) associated with a mechanism in
charge of signal interpretation, Jimenez & Leon (2009).
The first register of a biosensor was the enzymatic sensor, designed in 1962 by Narang in
New York and specialized in determining the concentration of glucose in blood by means of
the reaction catalyzed by glucose oxidase, coupling glucose oxidase to an oxygen selective
electron, (Narang, U, 1994) .Next, immobilized enzymes were strengthened in clinical
diagnostics, which could be used in the development and implementation of biosensors in
urea.Other authors point out that one of the first biosensors developed was the one
responsible for measuring/detecting the pH.
The types of biosensors are classified into electrochemical, thermometric, piezoelectric,
optical, cellular. Electrochemical biosensors are the most common type of biosensor
because of their high sensitivity and selectivity, as well as their low cost and ease of
manufacture. However, they require a constant power supply and are susceptible to
interference from other substances in the sample. Thermometric biosensors are used to
detect temperature changes and among their characteristics are their high sensitivity and
their ability to operate in a wide range of environmental conditions, but they are slow to
respond and are not very specific. Piezoelectric biosensors use a piezoelectric material.
Optical biosensors use a light-sensitive device to detect the presence of an analyte. Cellular
biosensors have living cells that are used as signal transducers. These cells can be
prokaryotic or eukaryotic. Prokaryotes are cells that lack a nucleus and membranous
organelles, such as mitochondria. Cellular biosensors can be used to detect and measure a
variety of biomolecules and biological compounds. Immunosensors are a subset of cellular
biosensors that use immune cells to detect and measure biomolecules and biological
compounds.
Although the initial developments in biosensor technology were applied in clinical chemistry,
its spectrum has increased and its versatility has allowed us to venture into the analysis of
organic and inorganic compounds and environmental, food, cosmetic and pharmaceutical
matrices, among others. In food matrices, in the analysis of the composition, xenobiotic
compounds such as pesticides, dioxins, drugs, additives, polyaromatic hydrocarbons stand
out; pathogens and toxins of bacterial origin, traceability processes, determination of
genetically modified organisms, allergens, antinutrients, process control and stability.
The combination of biosensors with DNA sequences and different types of transducers, such
as piezoelectrics, constitutes a powerful tool for the analysis of genetically modified
organisms (64-65), which are rigorously controlled in economic blocs such as the European
Union. This is complemented by molecular biology techniques, with which great results have
been obtained in the analysis of viruses and prions.
The analysis of chemical and biological contaminants constitutes an analytical and social
challenge for the agri-food industries. Obtaining results in a timely manner allows decisions
to be made that guarantee the obtaining of safe and innocuous products and, at the same
time, save large sums of money.
Reference
Lei, Y., Chen, W., & Mulchandani, A. (2006). Microbial biosensors. Analytica Chimica Acta,
568(1-2), 200–210. doi:10.1016/j.aca.2005.11.065
J, B., Chanda, K., & MM, B. (2018). Biosensors for pathogen surveillance. Environmental
Chemistry Letters. doi:10.1007/s10311-018-0759-y
Narang, U., Prasad, P. N., et. al. (1994). Glucose Biosensor Based on a Sol-Gel-Derived
Platform. Analytical Chemistry, 66(19), 3139–3144. doi:10.1021/ac00091a023
Jiménez C., & Leon E. (2009). Biosensores: aplicaciones y perspectivas en el control y
calidad de procesos y productos alimenticios. Vitae, 16(1), 144-154.