Abstract
A toxicity electrochemical DNA biosensor has been constructed for the detection of carcinogens using 24 base guanine DNA rich single stranded DNA, and methylene blue (MB) as the electroactive indicator. This amine terminated ssDNA was immobilized onto silica nanospheres and deposited on gold nanoparticle modified carbon-paste screen printed electrodes (SPEs). The modified SPE was initially exposed to a carcinogen, followed by immersion in methylene blue for an optimized duration. The biosensor response was measured using differential pulse voltammetry. The performance of the biosensor was identified on several anti-cancer compounds. The toxicity DNA biosensor demonstrated a linear response range to the cadmium chloride from 0.0005 ppm to 0.01 ppm (R2 = 0.928) with a limit of detection at 0.0004 ppm. The biosensor also exhibited its versatility to screen the carcinogenicity of potential anti-cancer compounds.
Highlights
Chemicals that possess carcinogenicity are classified by various bodies including the InternationalAgency for Research on Cancer (IARC)
An electrochemical DNA biosensor with a 24 base guanine-rich nucleotide was constructed by using methylene blue as the indicator and silica nanoparticles as an immobilization platform
This toxicity electrochemical DNA biosensor was developed for the purpose of evaluating the carcinogenicity of anticancer compounds
Summary
These DNAs are usually favored since they can be extracted in large quantities, are able to replace human DNA in many applications, and are commercially accessible These DNAs have very long DNA sequences, which is not ideal in building a DNA biosensor as it may fold onto itself when immobilized onto an electrode [3]. This will reduce the DNA surface that is able to interact with the carcinogen. The utilization of single stranded DNAs (ssDNA) in the construction of biosensors yielded stronger nucleobases responses [6] compared to double stranded DNAs (dsDNA) This is because ssDNA has bases that are exposed to the environment which enables easy access for carcinogen interaction. The biosensor is employed as a complementary toxicity assessment on carcinogenicity of fourteen biological potential N-heterocyclic compounds that were previously synthesized in the group
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
