Simple Colorimetric Assay for Vibrio parahaemolyticus Detection Using Aptamer-Functionalized Nanoparticles

Abstract

Simple, rapid, and sensitive screening methods are the key to prevent and control the spread of foodborne diseases. In this study, a simple visual colorimetric assay using magnetic nanoparticles (MNPs) and gold nanoparticles (AuNPs) was developed for the detection of Vibrio parahaemolyticus . First, the aptamer responding to V. parahaemolyticus was conjugated onto the surface of MNPs and used as a specific magnetic separator. In addition, the aptamer was also immobilized on the surface of AuNPs and used as a colorimetric detector. In the presence of V. parahaemolyticus , a sandwich structure of MNP–aptamer–bacteria–aptamer–AuNPs is formed through specific recognition of the aptamer and V. parahaemolyticus . The magnetic separation technique was then applied to generate a detection signal. Owing to the optical properties of AuNPs, a visual signal could be observed, resulting in an instrument-free colorimetric detection. Under optimal conditions, this assay shows a linear response toward V. parahaemolyticus concentration through the range of 10–10 6 cfu/mL, with a limit of detection of 2.4 cfu/mL. This method was also successfully applied for V. parahaemolyticus detection in spiked raw shrimp samples.

Selective Detection of Legionella pneumophila Serogroup 1 and 5 with a Digital Photocorrosion Biosensor Using Antimicrobial Peptide-Antibody Sandwich Strategy

“…However, SPR biosensors are also sensitive to temperature variations and require special temperature-stabilized chambers [ 19 ]. Colorimetric paper-based biosensors [ 15 , 20 ] are potentially attractive due to their ability to monitor the presence of specific pathogens by detecting change in colors distinguishable with a naked eye. However, the major limitation of colorimetric assays is their low sensitivity since it is often difficult to transform biochemical reactions into measurable color changes [ 20 ].…”

“…Colorimetric paper-based biosensors [ 15 , 20 ] are potentially attractive due to their ability to monitor the presence of specific pathogens by detecting change in colors distinguishable with a naked eye. However, the major limitation of colorimetric assays is their low sensitivity since it is often difficult to transform biochemical reactions into measurable color changes [ 20 ]. An innovative biosensing method based on digital photocorrosion (DIP) of GaAs/AlGaAs semiconductor nanoheterostructures has been recently introduced for rapid detection of L. pneumophila [ 21 , 22 ].…”

Aptamers: A prospective tool for infectious diseases diagnosis

“…76 The biosensor is anticipated to be utilized for the quick of Vibrio parahaemolyticus by aptamers and the formation of a special sandwich structure with a detection limit of 2.4 CFU/ml. 79 (Table 2). 87…”

“…Taking Vibrio parahaemolyticus as an example, the main limitations of the current standard analytical methods for the detection of Vibrio parahaemolyticus (V.P) are cumbersome equipment, cumbersome operation and longtime 78 . While Sadsri et al achieved the detection of V.P through the specific recognition of Vibrio parahaemolyticus by aptamers and the formation of a special sandwich structure with a detection limit of 2.4 CFU/ml 79 . Wu et al introduced an aptamer‐based SERS method for single‐step detection of Vibrio parahaemolyticus in seafood with a detection limit of 12 CFU/ml 80,81 …”

Biosensors and Point‐of‐Care Devices for Bacterial Detection: Rapid Diagnostics Informing Antibiotic Therapy

“…[121] A better LOD of 2.4 CFU mL −1 was obtained by Sadsri et al using V. Parahaemolyticus aptamerfunctionalized AuNPs as the signal detector. [122] However, they incorporated V. Parahaemolyticus aptamer-functionalized MNPs in their system to create a sandwich assay. This allowed for effective capture of the bacteria and their subsequent magnetic separation, hence triggering fading of the color of the solution.…”