Nano-Biotechnology for Bacteria Identification and Potent Anti-bacterial Properties: A Review of Current State of the Art

Abstract

Sepsis is a critical disease caused by the abrupt increase of bacteria in human blood, which subsequently causes a cytokine storm. Early identification of bacteria is critical to treating a patient with proper antibiotics to avoid sepsis. However, conventional culture-based identification takes a long time. Polymerase chain reaction (PCR) is not so successful because of the complexity and similarity in the genome sequence of some bacterial species, making it difficult to design primers and thus less suitable for rapid bacterial identification. To address these issues, several new technologies have been developed. Recent advances in nanotechnology have shown great potential for fast and accurate bacterial identification. The most promising strategy in nanotechnology involves the use of nanoparticles, which has led to the advancement of highly specific and sensitive biosensors capable of detecting and identifying bacteria even at low concentrations in very little time. The primary drawback of conventional antibiotics is the potential for antimicrobial resistance, which can lead to the development of superbacteria, making them difficult to treat. The incorporation of diverse nanomaterials and designs of nanomaterials has been utilized to kill bacteria efficiently. Nanomaterials with distinct physicochemical properties, such as optical and magnetic properties, including plasmonic and magnetic nanoparticles, have been extensively studied for their potential to efficiently kill bacteria. In this review, we are emphasizing the recent advances in nano-biotechnologies for bacterial identification and anti-bacterial properties. The basic principles of new technologies, as well as their future challenges, have been discussed.

Keywords: anti-bacterial activity; antimicrobial resistance; bacteria identification; nanotechnology; sepsis.

Figure 5

(A) Schematic representation of anti-bacterial activity of metal or drug encapsulated polymeric NPs; (B) Comparative TEM images of E. faecalis in the absence and presence of synthesized polymer; and (C) the number of bacteria present on wounds; swab culture was used for checking bacteria load at day 8 after injury (* indicate p < 0.05 compared with untreated group). Reproduced with permission from [139,142,143]. Copyright 2018, Frontiers; copyright 2014, Royal Society of Chemistry; copyright 2019, MDPI.

Figure 6

(A) Schematic representation of photothermal ablation of bacteria incubated with metallic nanoparticles in the presence of NIR; (B) photothermal image of E. coli and P. aeruginosa with mannose functionalized AuNRs, showing temperature before (I, III) and after treatment (II, IV); and (C) scanning electron microscopy (SEM) images of E. coli and E. faecalis where (a,b) are SEM images of untreated cells, and (a′,b′,a″,b″) are dead bacteria, post NIR treatment. Reproduced with permission from [160,162]. Copyright 2019, Elsevier; copyright 2014, Royal Society of Chemistry.

Figure 1

(A) The representative Gram-positive and Gram-negative bacteria causing sepsis; (B) the mechanism of sepsis. Reproduced with permission from [20]. Copyright 2018, Wiley.

Figure 2

Methods for bacterial identification with (A) culture-based method, (B) PCR-based method. Reproduced with permission from [47,54]. Copyright 2020, Wiley; copyright 2020, Springer.

Figure 3

Workflow of MALDI-TOF-MS for bacterial identification. Some liquid samples such as (A) urine, (B) positive blood culture bottles, and (C) cerebrospinal fluid can be applied for direct identification following some sample preparation and extraction protocol, and (D) bacterial culture from standard agar plate. Reproduced with permission from [67]. Copyright 2020, Elsevier.

Figure 4

(A) Workflow for bacterial identification using SERS, (B) workflow for accurate bacterial identification using deep-learning strategy, and (C) measurement of Raman signals from the solutions in a multi-well array showing specificity for target bacteria. Reproduced with permission from [97,104,110]. Copyright 2022, American Chemical Society; copyright 2020, Wiley; copyright 2021, Elsevier.

Figure 7

(A) Three-dimensional representation of the modeled interactions between a rod-shaped cell and the wing surface. The cell into contact (a1), adsorb onto the nanopillars (a2), and rupturing of cell wall by nanopillars (a3). Bacterial cell on the flat surface (b1) or nanopatterned surface (b2). (B) Schematic representation of rupturing of S. aureus after incubation with gold nanostars embedded in hydrogel, and (C) representative SEM images of the BLS Salmonella (isolates 44, 79, and 83) appeared to be significantly penetrated through interaction with the sharp NWs. Reproduced with permission from [176,181,182]. Copyright 2017, Elsevier; copyright 2022, American Chemical Society; copyright 2020, American Association for the Advancement of Science. Scale bars, 500 nm.