Nano-aluminosilicate on interdigitated electrode as genosensor for determining epidermal growth factor receptor mutation in non-small cell lung Carcinoma

Lung cancer is caused by mutations of the epidermal growth factor receptor (EGFR), which play an important role in non-small cell lung cancer (NSCLC) diagnosis. The present research demonstrates a specific and sensitive genosensor designed to detect EGFR mutation. Firstly, aluminosilicate was synthesized from joss fly ash. Morphological and structural analyses revealed the size of aluminosilicate to be ~25 nm, affirming the uniformly spherical shaped nanostructure, further revealing its physiochemical properties. Then, the research justified the promising application of aluminosilicate as drug carriers, through enzyme-linked apta-sorbent assay and antimicrobial analysis, claiming that the performance of aluminosilicate conjugated ampicillin is better. Next, the research execution encompasses the fabrication of interdigitated aluminium electrode (AlIDE) with four different microscale gap sizes, 400, 100, 60 and 45 μm. Aluminosilicate synthesized from joss fly ash was deposited on the least variated AlIDE (400 and 100 μm) upon ionic flux and electrolyte scouting performed. Based on the results, optimum microscale gap for aluminosilicate deposition is 100 μm gap sized AlIDE, selected for the development of geneosensor for NSCLC diagnosis. Third execution is the validation of designed oligonucleotides through genomic DNA-based colorimetric assay on unmodified gold nanoparticles (GNPs) for EGFR detection. GNPs aggregation were evidenced by microscopic analyses. The assay resulted a detection limit of 313 nM with mutant target strand. The last research execution is the development of genosensor with nano-aluminosilicate synthesized from joss fly ash was deposited on AlIDE for DNA immobilization and hybridization. Fourier-transform Infrared Spectroscopy analysis was performed at every step of surface functionalization to evident the relevant chemical bonding of biomolecules. Genosensor depicts a sensitive EGFR mutation as it is able to detect apparently at 100 aM mutant against 1 μM DNA probe. An insignificant voltammetry signal generated with wild type strand. With the absence of aluminosilicate, the sensitivity of genosensor is reduced significantly, specifying the important role of aluminosilicate in sensing. Based on the slope of the calibration curve, the attained sensitivity of aluminosilicate modified genosensor was 3.02E-4 A M-1. The detection limit of genosensor computed based on 3σ calculation is 100 aM. Finally, the aims of this research were achieved by developing a rapid and accurate diagnostic device, where the nano-aluminosilicate extracted from joss fly ash significantly enhance the genosensor sensitivity for NSCLC detection.