Quick and simple estimation of bacteria using a fluorescent paracetamol dimer-Au nanoparticle composite

Area of Science:

• Analytical Chemistry
• Nanotechnology
• Biotechnology

Background:

• Accurate bacterial detection is crucial for public health and environmental safety.
• Conventional methods for bacterial enumeration can be time-consuming and complex.
• Development of rapid, sensitive, and simple detection techniques is highly desirable.

Purpose of the Study:

• To develop a facile method for the detection and enumeration of bacterial contamination.
• To utilize a novel fluorescent nanocomposite for bacterial sensing.
• To assess the potential of this method as an alternative to conventional bacterial detection techniques.

Main Methods:

• Synthesis of a fluorescent nanocomposite comprising paracetamol dimer (PD) and gold nanoparticles (Au NPs).
• Characterization of the nanocomposite using UV-Vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction, and selected area electron diffraction.
• Detection and enumeration of bacterial strains based on the fluorescence quenching of the nanocomposite.

Main Results:

• The synthesized nanocomposite exhibited fluorescence emission at 435 nm upon excitation at 320 nm.
• The method successfully detected six bacterial strains with a limit of detection of 100 CFU mL(-1).
• Differential fluorescence quenching allowed for the distinction between gram-positive and gram-negative bacteria.
• TEM analysis confirmed interaction with bacteria without causing apparent damage.
• Chi-square testing validated the accuracy of the developed method.

Conclusions:

• The developed fluorescent nanocomposite offers a quick, non-specific, and highly sensitive method for bacterial detection and enumeration.
• This approach demonstrates significant potential as a viable alternative to conventional bacterial detection methods.
• The method's ability to differentiate bacterial types and its high sensitivity make it valuable for various applications.