Biology Reference
In-Depth Information
Figure 9.12.
Ply genosensor responses for different concentrations of
complementary target (ply, white bars) and the single-base mismatch
target (plymisms1, grey bars) when 25% formamide is included in the
hybridization buffer. Data are given as average
SD (
n
= 3). (a) Enzymatic
and (b) electrocatalytic detection. Reproduced with permission from ACS
[29,54].
±
9.4.2
Alkaline Phosphatase-Catalyzed Silver Deposition for
Electrochemical Detection
In this section a new substrate solution is described that combines
an indoxyl compound, 3-indoxyl phosphate (3-IP), and silver ions.
The resulting enzymatic product of 3-IP is indigo blue, an aromatic
heterocycle insoluble in aqueous solutions. Two strategies can be
carried out to detect the product: its sulfonation in acidic medium,
giving rise to indigo carmine (IC), or its solubilization in basic
medium and in the presence of dithionite salt, giving rise to
leucoindigo.Themaindrawbackofthesemethodologiesisthat,inall
cases, it is necessary to add a step for detection after the enzymatic
reaction and the use of aggressive agents such as concentrated
