Aptamers functionalized metal and metal oxide nanoparticles: Recent advances in heavy metal monitoring

International audience ; Heavy metal contamination has long been a major hazard to the entire ecological system and human beings. Consequently, sensitive and reliable methods have been developed for the detection of heavy metal ions from different systems. Advancements in biotechnology, and in functional nucleic acids specifically, have offered new methods for heavy metal monitoring based on the specific interactions of aptamers with heavy metal ions. The introduction of nanoparticles to aptamer-based technologies has also presented its advantages of increased immobilization efficiency, sensitivity and selectivity. Thus, this review provides an update on the progress of using aptamers functionalized nanoparticles for the monitoring of heavy metal ions. The aptamer-based detection of heavy metal ions using metallic and metallic oxide nanoparticles are emphasized. Even though gold nanoparticles are the most commonly used with aptamers for the detection of heavy metal ions reporting extremely low detection limits, several other nanoparticles have emerged as promising modifications to aptamers in heavy metal monitoring as well. Comparing the different techniques used, electrochemical methods have presented the best performance while offering their advantages over optical and spectrometric techniques.