Abstract
This work investigates the surface plasmon resonance (SPR) response of 50-nm thick nano-laminated gold film using Kretschmann-based biosensing for detection of urea and creatinine in solution of various concentrations (non-enzymatic samples). Comparison was made with the presence of urease and creatininase enzymes in the urea and creatinine solutions (enzymatic samples), respectively. Angular interrogation technique was applied using optical wavelengths of 670 nm and 785 nm. The biosensor detects the presence of urea and creatinine at concentrations ranging from 50–800 mM for urea samples and 10–200 mM for creatinine samples. The purpose of studying the enzymatic sample was mainly to enhance the sensitivity of the sensor towards urea and creatinine in the samples. Upon exposure to 670 nm optical wavelength, the sensitivity of 1.4°/M was detected in non-enzymatic urea samples and 4°/M in non-enzymatic creatinine samples. On the other hand, sensor sensitivity as high as 16.2°/M in urea-urease samples and 10°/M in creatinine-creatininase samples was detected. The enhanced sensitivity possibly attributed to the increase in refractive index of analyte sensing layer due to urea-urease and creatinine-creatininase coupling activity. This work has successfully proved the design and demonstrated a proof-of-concept experiment using a low-cost and easy fabrication of Kretschmann based nano-laminated gold film SPR biosensor for detection of urea and creatinine using urease and creatininase enzymes.
Highlights
End stage renal disease (ESRD) or commonly known as kidney failure is one of the major public health problems affecting approximately 10% of the world population
In order to characterize the behaviour of nano-laminated gold film surface plasmon resonance (SPR)-based sensor in different thickness, reflectivity was plotted against incident angle in SPR response curves as obtained from the finite difference time domain (FDTD) numerical analysis
The numerical analysis conducted in angular interrogation mode with changes of optical parameter for a 50 nm-thick nano-laminated gold film SPR sensor gave plots of reflectivity versus incident angle
Summary
End stage renal disease (ESRD) or commonly known as kidney failure is one of the major public health problems affecting approximately 10% of the world population. The number of the ESRD patients that require haemodialysis continue to rise mainly due to the increase in cases of hypertension and diabetes and in the growing elderly population. Kidney failure is often manifested by the unusual albumin secretion and decreased kidney function. Urea concentration ranges from 30–150 mM while the normal level range is between 2.5–6.7 mM [1].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
