Extraction and electrochemical detection for quantification of trace-level DNA

• Published in: Mikrochimica acta (1966) 2021-06, Vol.188 (6), p.180-180, Article 180
• Main Authors: Cotchim, Suparat, Thavarungkul, Panote, Kanatharana, Proespichaya, Thanakiatkrai, Phuvadol, Kitpipit, Thitika, Limbut, Warakorn
• Format: Article
• Language: English
• Subjects: Acetic acid; Acrylic acid; Acrylic Resins - chemistry; Adsorption; Aminopropyltriethoxysilane; Analytical Chemistry; Characterization and Evaluation of Materials; Chemical Fractionation - methods; Chemistry; Chemistry and Materials Science; DNA - analysis; DNA - chemistry; DNA - isolation & purification; Electrochemical analysis; Electrochemical Techniques - instrumentation; Electrochemical Techniques - methods; Electrodes; Ferric oxide; Glassy carbon; Humans; Iron compounds; Iron oxides; Limit of Detection; Magnetic Iron Oxide Nanoparticles - chemistry; Methylene blue; Methylene Blue - chemistry; Microengineering; Mouth Mucosa - chemistry; Nanochemistry; Nanoparticles; Nanotechnology; Organic acids; Original Paper; Oxidation; Polyacrylic acid; Propylamines - chemistry; Reproducibility of Results; Sensors; Silanes - chemistry; Silver chloride
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-021-04825-x

A novel strategy was developed to extract, detect, and quantify trace-level DNA. For the extraction step, a composite of methylene blue (MB), poly(acrylic acid) (PAA), and modified iron oxide magnetic nanoparticles (IOMNPs) (PAA/IOMNPs) was used to adsorb DNA from the sample. MB-PAA/IOMNPs with adsorbed DNA were then separated from the solution with an external magnet and MB-DNA was eluted from PAA/IOMNPs with acetic acid. In the detection step, MB-DNA was adsorbed on the surface of 3-aminopropyltriethoxysilane (APTES)–modified glassy carbon electrode via electrostatic force. DNA was quantified by measuring the oxidation peak of MB at a potential −0.13 V vs. Ag/AgCl using differential pulse voltammetry. Under the optimal experimental conditions, the DNA sensor showed linear ranges from 0.001 to 0.005 pg μL −1 , 0.005 to 0.070 pg μL −1 , and 0.070 to 0.400 pg μL −1 and a limit of detection of 0.87 fg μL −1 . The proposed sensor detected trace DNA in real samples with recoveries that ranged from 80.4 to 90.4%. Graphical abstract