Pyran Heterocyclic Compound as the Prosperous Scaffolds for Biological Sensor (A-Review)

2H-pyrans and 4H-pyrans, which are six-membered heterocyclic compounds containing oxygen, are a class of biologically dynamic natural and synthetic products that played a key character in bioorganic chemistry and continue to pique attention. Pyrans and their analogues have a prominent position in bioorganic chemistry because of their numerous applications. This analysis explored the most recent advances, as well as the discovery of new methodologies and the diverse biological activities of pyran analogues.

Analysis of Amoxicillin’s Antibacterial Activity Using Biological Sensor With Clit Acoustic Wave

The possibility of antibacterial activity assay using an acoustic non-contact biological sensor based on two piezoelectric plates separated by an air gap was demonstrated on the example of amoxicillin and Escherichia coli for the first time. An acoustic wave with transverse horizontal polarization is excited in the bottom plate of the sensor. The upper plate serves as the bottom of the container with the studied cell suspension. It was shown that the addition of an antibiotic to the cell suspension leads to a change in the parameters of the sensor. The effect of amoxicillin on microbial cells was monitored by laser microscopy and standard microbiological culture. The possibility of express analysis of the drug’s antibacterial activity using a biological sensor based on the use of a slit acoustic wave is shown.

Analysis of the antibacterial activity of ampicillin by biological sensor based on a microwave resonator

A method has been developed for analyzing the activity of antibacterial drugs on ampicillin as example by using a biological sensor based on a microwave resonator with an analysis time of ~ 15 minutes.

Rapid and Real-Time Measurement of Membrane Potential Through Intramembrane Field Compensation

Synthetic lipid membranes are self-assembled biomolecular double layers designed to approximate the properties of living cell membranes. These membranes are employed as model systems for studying the interactions of cellular envelopes with the surrounding environment in a controlled platform. They are constructed by dispersing amphiphilic lipids into a combination of immiscible fluids enabling the biomolecules to self-assemble into ordered sheets, or monolayers at the oil-water interface. The adhesion of two opposing monolayer sheets forms the membrane, or the double layer. The mechanical properties of these synthetic membranes often differ from biological ones mainly due to the presence of residual solvent in between the leaflets. In fact, the double layer compresses in response to externally applied electrical field with an intensity that varies depending on the solvent present. While typically viewed as a drawback associated with their assembly, in this work the elasticity of the double layer is utilized to further quantify complex biophysical phenomena. The adsorption of charged molecules on the surface of a lipid bilayer is a key property to decipher biomolecule interactions at the interface of the cell membrane, as well as to develop effective antimicrobial peptides and similar membrane-active molecules. This adsorption generates a difference in the boundary potentials on either side of the membrane which may be tracked through electrophysiology. The soft synthetic membranes produced in the laboratory compress when exposed to an electric field. Tracking the minimum membrane capacitance allows for quantifying when the intrinsic electric field produced by the asymmetry is properly compensated by the supplied transmembrane voltage. The technique adopted in this work is the intramembrane field compensation (IFC). This technique focuses on the current generated by the bilayer in response to a sinusoidal voltage with a DC component, VDC. Briefly, the output sinusoidal current is divided into its harmonics and the second harmonic equals zero when VDC compensates the internal electric field. In this work, we apply the IFC technique to droplet interface bilayers (DIB) enabling the development of a biological sensor. A certain membrane elasticity is needed for accurate measurements and is tuned through the solvent selection. The asymmetric DIBs are formed, and an automated PID-controlled IFC design is implemented to rapidly track and compensate the membrane asymmetry. The closed loop system continuously reads the current and generates the corresponding voltage until the second harmonic is abated. This research describes the development and optimization of a biological sensor and examines how varying the structure of the synthetic membrane influences its capabilities for detecting membrane-environment interactions. This platform may be applied towards studying the interactions of membrane-active molecules and developing models for the associated phenomena to enhance their design.