Nanomaterials for Biosensing Lipopolysaccharide

Abstract

Lipopolysaccharides (LPS) are endotoxins, hazardous and toxic inflammatory stimulators released from the outer membrane of Gram-negative bacteria, and are the major cause of septic shock giving rise to millions of fatal illnesses worldwide. There is an urgent need to identify and detect these molecules selectively and rapidly. Pathogen detection has been done by traditional as well as biosensor-based methods. Nanomaterial based biosensors can assist in achieving these goals and have tremendous potential. The biosensing techniques developed are low-cost, easy to operate, and give a fast response. Due to extremely small size, large surface area, and scope for surface modification, nanomaterials have been used to target various biomolecules, including LPS. The sensing mechanism can be quite complex and involves the transformation of chemical interactions into amplified physical signals. Many different sorts of nanomaterials such as metal nanomaterials, magnetic nanomaterials, quantum dots, and others have been used for biosensing of LPS and have shown attractive results. This review considers the recent developments in the application of nanomaterials in sensing of LPS with emphasis given mainly to electrochemical and optical sensing.

Chitosan Stabilized Silver Nanoparticles for the Electrochemical Detection of Lipopolysaccharide: A Facile Biosensing Approach for Gram-Negative Bacteria

“…In comparison, the LOQ is the lowest concentration of the analyte in a sample that can be determined with acceptable precision and accuracy under the stated conditions of the test [42]. The LOD of the biosensor is ~0.001 ng/mL, which is extremely competitive in comparison to recent reports on LPS biosensors [10]. The LOQ of the biosensor is ~0.003 ng/mL.…”

“…Lipopolysaccharide (LPS) is a major component of the outer membrane of Gram-negative bacteria and is an endotoxin [9,10]. Human exposure to microbial endotoxins, either by direct contact or in a systemic manner, can result in inflammatory reactions, leading to multiple organ failure, shock, and even death [11].…”

Electrodeposition of Nanoporous Gold Thin Films

“…The potential of nanostructured metallic surfaces has also been seen in optical applications and has been demonstrated for biosensing applications, SERS, guiding and manipulating light, and trapping of micro-sized particles [92]. The electrodeposition approach has been used for depositing a thin layer of AuNPs from 10 mM HAuCl 4 for 20 s at −0.2 V (vs. Ag/AgCl) yielding oblate particles of 200 nm average diameter that immobilized an aptamer specific for LPS detection achieving a linear range of 0.1-10.24 ng mL −1 [93]. Thin nanoporous membranes of gold are best suited to the examination of surface plasmons as the analyte can get into the pores of NPG and can modify their dielectric atmosphere are detectable via absorption peaks in SPR Figure 7.…”

Application of Zero-Dimensional Nanomaterials in Biosensing

“…Compared with bulk high-dimensional nanomaterials, 0D nanomaterials are mostly spherical or quasi-spherical nanoparticles with a diameter of less than 100 nm Chen J. B. et al, 2019;Sondhi et al, 2020). With such novel properties as optical stability, wavelength-dependent photoluminescence, chemical inertness, cellular permeability and biocompatibility, 0D nanomaterials offer great adaptability to biomedical applications such as nanomedicine, cosmetics, bioelectronics, biosensor and biochip (Koh and Josephson, 2009;Yao et al, 2018).…”

“…One of the main challenges in the field of biosensor is to develop highly sensitive biosensors by increasing the active surface area, electrochemical activity and conductivity or optical performance of biosensors (Pirzada and Altintas, 2019;Dhenadhayalan et al, 2020). Therefore, 0D nanomaterials as a powerful sensing material are utilized as an important probe to increase the sensitivity of biosensors and thus enhance their analytical performance due to their conductive properties and special optical properties (Carneiro et al, 2019;Sondhi et al, 2020).…”