Table 2.

Comparison of the proposed miRNA-21 platform with other electrochemical-based approaches

Platform	LOD	Matrix	Required tasks	Ref
LNA-integrated nucleic acid hairpin probe, biotin-labeled bridge DNA–AuNPs–bio-barcode, enzymatic signal amplification	6 fM (buffer)	Human hepatocarcinoma cells extract	Addition of HRP, H2O2, hydroquinone	[56]
ssDNA/pSAM/ITO recognized RNA, and ALP-conjugated JAZ binds RNA–DNA hybrid	30 fM	tenfold diluted serum	Cell stored for 10’ at 37 °C in TZ buffer with Ru(NH3)63+, HQDP, TCEP	[57]
Sulfonamide-bound antisense hybridization	20 fM (buffer)	Urine after proteinase K digestion by spin-filtration	30’ shaking at 50 °C, addition of external electrochemical probe (ferricyanide)	[58]
Magnetosensing platform using p19 viral protein as receptor	0.45 nM (buffer)	Breast cancer cells Extract	Magnetic beads, HRP, H2O2, 75’	[59]
miRNA-DNA-MB hybridization onto AuNPs	2 nM	Urine	Addition of NaCl	This work

LNA, locked nucleic acid; ssDNA, single stranded DNA; pSAM, polymeric self-assembled monolayer; ITO, indium − tin oxide; ALP: alkaline phosphatase; JAZ, just another zinc finger protein ZNF346; HRP, horseradish peroxidase