Portable microfluidic integrated plasmonic platform for pathogen detection.

Onur Tokel,Okan Oner Ekiz,Shruthi Rao,Burak Turker,Umit Hakan Yildiz,Utkan Demirci,Nalini Natarajan,Naside Gozde Durmus,Hadi Shafiee,Fatih Inci,Kaushik Sridhar,Aykutlu Dana,Can Cetin

doi:10.1038/srep09152

Abstract

Timely detection of infectious agents is critical in early diagnosis and treatment of infectious diseases. Conventional pathogen detection methods, such as enzyme linked immunosorbent assay (ELISA), culturing or polymerase chain reaction (PCR) require long assay times, and complex and expensive instruments, which are not adaptable to point-of-care (POC) needs at resource-constrained as well as primary care settings. Therefore, there is an unmet need to develop simple, rapid, and accurate methods for detection of pathogens at the POC. Here, we present a portable, multiplex, inexpensive microfluidic-integrated surface plasmon resonance (SPR) platform that detects and quantifies bacteria, i.e., Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) rapidly. The platform presented reliable capture and detection of E. coli at concentrations ranging from ~105 to 3.2 × 107 CFUs/mL in phosphate buffered saline (PBS) and peritoneal dialysis (PD) fluid. The multiplexing and specificity capability of the platform was also tested with S. aureus samples. The presented platform technology could potentially be applicable to capture and detect other pathogens at the POC and primary care settings.

Highlights

Detection of infectious agents is critical in early diagnosis and treatment of infectious diseases
It was previously shown that anti-LPS presented highest capture efficiency among a set of antibodies for on-chip E. coli capture when Protein G based surface chemistry was performed[6]
In the second limit of detection (LOD) approach, we evaluated the absolute number of cells that the system is sensitive to, which was defined as the absolute LOD

Summary

Introduction

Detection of infectious agents is critical in early diagnosis and treatment of infectious diseases. Emerging micro- and nano-scale bioengineering and biomedical technologies have provided broad applications (e.g., medical diagnostics and biosensors) in health sciences Developing such platforms that are affordable and rapid for infectious diseases is one of the top priorities for improving human health at the point-of-care (POC) settings[1,2,3,4]. With the ongoing miniaturization in electronics, emerging technologies could allow portable instruments and minimize the need for bulky laboratory infrastructure at the POC and primary care settings[9] Such self-contained and robust diagnostic devices could lead to developing strategies for disease monitoring and management[10]. We present such a microfluidic-based SPR technology We validated this portable platform with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) spiked samples as a model pathogen detection system. Multiplexing and selectivity capability was assessed with S. aureus spiked in PBS samples

Methods

Results

Conclusion