A Comparison between Silver Nanosquare Arrays and Silver Thin-Films as a Blood Cancer Prognosis Monitoring Electrode Design Using Optical and Electrochemical Characterization.

Nasori Nasori,Dawei Cao,Endarko Endarko,Ihwanul Aziz,Miftakhul Firdhaus,Vinda Zakiyatuz Zulfa,Agus Rubiyanto,Darsono Darsono,Zhijie Wang,Ulya Farahdina

doi:10.3390/nano11113108

Abstract

The development of silver (Ag) thin films and the fabrication of Ag nanosquare arrays with the use of an anodic aluminum oxide (AAO) template and leaf extracts were successfully carried out using the DC sputtering and spin coating deposition methods. Ag thin films and Ag nanosquare arrays are developed to monitor cancer prognosis due to the correlation between serum albumin levels and prognostic factors, as well as the binding of serum albumin to the surface of these electrodes. Nanosquare structures were fabricated using AAO templates with varying diameters and a gap distance between adjacent unit cells of 100 nm. The nanosquare array with a diameter of 250 nm and irradiated with electromagnetic waves with a wavelength of around 800 nm possessed the greatest electric field distribution compared to the other variations of diameters and wavelengths. The results of the absorption measurement and simulation showed a greater shift in absorption peak wavelength when carried out using the Ag nanosquare array. The absorption peak wavelengths of the Ag nanosquare array in normal blood and blood with cancer lymphocytes were 700–774 nm and 800–850 nm, respectively. The electrochemical test showed that the sensitivity values of the Ag thin-film electrode deposited using DC sputtering, the Ag thin-film electrode deposited using spin coating, and the Ag nanosquare array in detecting PBS+BSA concentration in the cyclic voltammetry (CV) experiment were 1.308 µA mM−1cm−2, 0.022 µA mM−1cm−2, and 39.917 µA mM−1cm−2, respectively. Meanwhile, the sensitivity values of the Ag thin film and the Ag nanosquare array in detecting the PBS+BSA concentration in the electrochemical impedance spectroscopy (EIS) measurement were 6593.76 Ohm·cm2/mM and 69,000 Ohm·cm2/mM, respectively. Thus, our analysis of the optical and electrochemical characteristics of Ag thin films and Ag nanosquare arrays showed that both can be used as an alternative biomedical technology to monitor the prognosis of blood cancer based on the concentration of serum albumin in blood.

Highlights

The early detection of tumours is vital for the treatment of cancer and can significantly increase the chance of survival by up to 12.4% [1,2]
The fabrication of Ag thin film and Ag nanosquare array electrodes were successfully carried out using the DC sputtering and spin coating deposition method
The results of the experiment and simulation showed a shift of peak absorbance towards a bigger wavelength as much as 26 to 150 nm at the Ag nanosquare array electrode with respect to an increase in the concentration of prognostic factors, namely bovine serum albumin (BSA) and leukocytes

Summary

Introduction

The early detection of tumours is vital for the treatment of cancer and can significantly increase the chance of survival by up to 12.4% [1,2]. Prabhakar et al [6] used the Nanomaterials 2021, 11, 3108. FTIR method to detect blood cancer and showed that blood with cancer had a greater absorption peak of 0.01 a.u than that of normal blood. Studies using the electrochemical technique have been carried out to detect various cancer biomarkers [8]. This type of experiment requires specific protein biomarkers for each type of cancer [9,10]. Leukaemia patients with low levels of serum albumin have a lower overall survival rate compared to patients with normal levels of serum albumin [12]. The reactive protein contained in commercial human serum albumin (HSA) is said to be very similar to the protein in bovine serum albumin (BSA) due to both HSA and BSA having the same structure and molecular weight [13,14]

Methods

Discussion

Conclusion