Silica nanoparticle assists determining liver cancer gene sequence on interdigitated electrode surface

Abstract

A high-performance interdigitated electrode (IDE) biosensing surface was reported here by utilizing self-assembled silica nanoparticle (SiNP). The modified surface was used to evaluate the complementation of hairpin forming region from Mitoxantrone resistance gene 7 (MXR7; liver cancer-related short gene). The conjugated SiNPs on 3-aminopropyl triethoxysilane functionalization were captured with probe sequence on IDE biosensing surface. The physical and chemically modified surface was used to quantify MXR7 and an increment in the current response upon complementation was noticed. Limit of target DNA detection was calculated (1-10 fM) and this label-free detection is at the comparable level to the fluorescent-based sensing. A linear regression was calculated [y = 0.243x − 0.0773; R 2 = 0.9336] and the sensitivity was 1 fM on the linear range of 1 fM to 10 pM. With the strong attachment of capture DNA on IDE through SiNP, the surface clearly discriminates the specificity (complementary) versus nonspecificity (complete-, single-, and triple-mismatched sequences). This detection strategy helps to determine liver cancer progression and the similar strategy can be followed for other gene sequence complementation.

Gold nanourchin enhances detection of Alzheimer's disease biomarker “miRNA‐137” on dual electrode sensing surface

“…The electrodes have cross-linked finger and gap regions with desired distances and numbers. 20,25,26 Upon molecular interaction or attachment on the sensing surface in the presence of power supply, there are dipole moments, which yield output signal changes. 20,[27][28][29] IDE has been designed to enhance both the selectivity and sensitivity by dropping a less sample of biological fluids on the electrode surface and measure the changes in resistance upon attachment/interaction of biomolecules.…”

“…IDE is generally a dielectrode system with positive and negative points and the charges supplied by a dual probe station. The electrodes have cross‐linked finger and gap regions with desired distances and numbers 20,25,26 . Upon molecular interaction or attachment on the sensing surface in the presence of power supply, there are dipole moments, which yield output signal changes 20,27–29 .…”