Surface Plasmon Resonance Biosensors

Special Article - Applications of Biosensors

Austin J Biosens & Bioelectron. 2019; 5(1): 1034.

Surface Plasmon Resonance Biosensors

Gorodkiewicz E1* and Lukaszewski Z2

1Department of Electrochemistry, University of Bialystok, Poland

2Faculty of Chemical Technology, Poznan University of Technology, Poland

*Corresponding author: Ewa Gorodkiewicz, Department of Electrochemistry, Institute of Chemistry, University of Bialystok, Ciolkowskiego 1K, 15-245 Bialystok, Poland

Received: July 06, 2019; Accepted: August 01, 2019; Published: August 08, 2019

Abstract

A review is made of 86 papers on surface plasmon resonance biosensors, published between 2016 and mid-2019. The reviewed papers are categorized into four groups, depending on the degree of maturity of the reported solution: ranging from simple marker detection to a mature biosensor and analytical procedure. Instrumental solutions and details of biosensor construction are analyzed, including the chips, receptors and linkers used, as well as calibration strategies. Papers concerning the determination of micro RNA and large particles such as vesicles, exosomes and cancer cells are also reviewed. Biosensors with a sandwich structure containing different nanoparticles are considered separately, as are SPR applications for investigating the interactions of biomolecules. An analysis is also made of the markers determined using the biosensors. Concluding, there is shown to be a growing number of SPR applications in the solution of real clinical problems.

Keywords: Surface plasmon resonance; Cancer markers; Biosensors; Receptor immobilization; Antibodies; Nanoparticles

Introduction

Biosensors are the subject of enormous expectations and are gradually gaining in diagnostic importance. These expectations are connected with what is called ‘liquid biopsy’, i.e. diagnosis based on analysis of body fluids such as blood, urine and saliva, and the possibility of early diagnosis of various cancers or other diseases. However, there is still a shortage of biosensors offering near 100% sensitivity and specificity, i.e. respectively 100% of true positive and 0% of false positive results. An illustration of the relationship between true positive and false positive results is provided by ROC curves. An example of such curves obtained with the use of an SPRi biosensor for the determination of podoplanin in blood serum and urine is given in Figure 1. This example is evidence that SPR biosensors can be useful tools in the evaluation of the diagnostic efficiency of new biomarkers.

An ideal biosensor should react exclusively to the target marker despite the presence of numerous similar proteins, glycoproteins, etc. in the analyzed body fluid. Moreover, the biosensor’s dynamic response range should include the concentrations of the marker found in the body fluid both of persons with the disease and of the healthy population. It is also expected that the precision of measurement of the marker concentration will be sufficient to distinguish between samples below and above a ‘cut-off’ value.

A limited number of measuring techniques are used successfully in combination with biosensors, the leader among which is ELISA. Surface Plasmon Resonance (SPR) is still only a promising technique. However, the number of applications of previously developed SPR biosensors in real clinical investigations is growing (Table 1).