A New Optical Fiber Probe-Based Quantum Dots Immunofluorescence Biosensors in the Detection of Staphylococcus aureus

Abstract

Staphylococcus aureus (S. aureus) is one of the most common clinical pathogenic bacteria with strong pathogenicity and usually leads to various suppurative infections with high fatality. Traditional bacterial culture for the detection of S. aureus is prone to diagnosis and antimicrobial treatment delays because of its long-time consumption and low sensitivity. In this study, we successfully developed a quantum dots immunofluorescence biosensor for S. aureus detection. The biosensor combined the advantages of biosensors with the high specificity of antigen-antibody immune interactions and the high sensitivity and stability of quantum dots fluorescence. The results demonstrated that the biosensor possessed high specificity and high sensitivity for S. aureus detection. The detection limit of S. aureus reached 1 × 104 CFU/ml or even 1 × 103 CFU/ml, and moreover, the fluorescence intensity had a significant positive linear correlation relationship with the logarithm of the S. aureus concentration in the range of 103–107 CFU/ml (correlation coefficient R2 = 0.9731, P = 0.011). A specificity experiment showed that this biosensor could effectively distinguish S. aureus (1 × 104 CFU/ml and above) from other common pathogenic (non-S. aureus) bacteria in nosocomial infections, such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii and Escherichia coli. Additionally, the whole detection procedure spent only 2 h. In addition, the biosensor in this study may not be affected by the interference of the biofilm or other secretions since the clinical biological specimens are need to be fully liquefied to digest and dissolve viscous secretions such as biofilms before the detection procedure of the biosensor in this study. In conclusion, the biosensor could meet the need for rapid and accurate S. aureus detection for clinical application.

Optically Active Nanomaterials and Its Biosensing Applications—A Review

“…In recent years, semiconductor QDs have witnessed a lot of attention due to their strong absorption, high stability and size-adjustable PL properties [71]. Different processes can be used to modify the surface of the QDs, allowing the experiment to obtain the QDs required [72].…”

“…Other than biomolecules, nanomaterials can also be used in the detection of cells and microorganism. In this context, Cui et al [72] developed the optical fiber probe and QDs immunofluorescence-based biosensor for detection of Staphylococcus aureus as shown in Figure 25. Developed biosensors exhibit advantage of high specificity between antigen and antibody's immune reaction, fluorescent labelling, transmission of fluorescent signal along optical fiber as well as high sensitivity and stability of QDs.…”

“…This sensing technology has promising uses for routinely checking the presence of different harmful bacteria in food and water supplies. Another study by Kaushik et The principle to identify S. aureus using the fiber probe, (c) prototype of the fiber optic biosensor, adopted from [72].…”

Advances in Novel Nanomaterial-Based Optical Fiber Biosensors—A Review

“…These gratings achieve surface plasmon resonance (SPR) effects and selective or enzymatic coatings, respectively. For sensitive and precise detection of bacterial flora and biomolecules, optical biosensors based on fluorescence [ 35 , 36 , 37 , 38 , 39 ], SPR [ 3 , 5 , 13 , 40 , 41 ], and localized surface plasmon resonance (LSPR) [ 7 , 18 , 42 , 43 ] are currently being reported.…”

Felodipine Determination by a CdTe Quantum Dot-Based Fluorescent Probe

“…CdTe QDs have excellent fluorescence performance, and they have a wide and continuous excitation spectrum, a narrow and symmetrical emission spectrum, high quantum yield and strong fluorescence performance, which makes them suitable for fluorescence sensors and biological imaging [ 15 , 16 ]. Various studies have shown that QDs with functional modification can be used for immunofluorescence detection and labelling of living samples, especially in the field of drug analysis [ 17 ]. In this paper, QDs were used as a fluorescence probe to determine the content of FEL tablets in vitro.…”