Electrochemcial characterisation and hybridisation efficiency of co-assembled monolayers of PEGylated ssDNA and mercaptohexanol on planar gold electrodes

Bipodal PEGylated alkanethiol for the enhanced electrochemical detection of genetic markers involved in breast cancer

“…Gradually increasing the content of the DT3 layer consequently increased the resistance to charge transfer to 2890 , 4080 , 6750 and 10,550 for ESR1:DT3 ratios of 1:1, 1:10, 1:100 and 1:1000, respectively. This behaviour is consistent with results previously presented on the study of the co-immobilisation of DNA probes and MCH (Henry et al, 2010).…”

“…The 1:100 co-immobilisation ratio was chosen based on previous studies (Henry et al, 2010). The sensors were exposed to 10 nM of the complementary sequence and further electrochemically detected after hybridisation with the reporter probe labelled with the enzyme HRP (URP) using pulsed amperometry (Fig.…”

Ultrasensitive, rapid and inexpensive detection of DNA using paper based lateral flow assay

“…Co-immobilization was explored as a means of controlling the probe surface density, as it is well known that spacing between the immobilised probes minimises steric hindrance, favouring accessibility to the complementary DNA strand. The ratio usually used for DNA to the short alkane thiol, mercaptohexanol (MCH) ranges between 1:10 and 1:10060. Additionally, to ensure that the thiol moiety on DNA is free, treatment with reducing agents such as DTT or TCEP is often incorporated in the conjugation protocol, thus breaking any disulphide bridges that may have formed between probes.…”

A reusable and label-free supersandwich biosensor for sensitive DNA detection by immobilizing target-triggered DNA concatamers on ternary self-assembled monolayer

“…Despite its many merits, the electrochemical DNA detection often suffers from instability, irreproducibility or time-consuming immobilization [13]. In order to overcome these shortcomings, many efforts have been devoted to control the packing density [13][14][15][16] and conformation of the recognition probes [17][18][19][20]. These strategies have effectively improved the hybridization efficiency and reproducibility which is affected by the crowding effect, entanglement or nonspecific interactions between probes, and substrate surface defects.…”