Table 3.

miRNA quantification technology

Technology	Advantages	Limitations	Citations
qPCR	• Current gold standard for sensitivity and specificity	• No genome-wide coverage	[74–76]
Microarray	• Commercially available reagents • Genome-wide coverage	• Specific probes • Specialized equipment • Lack of reproducibility between platforms • Difficult data normalization	[81–87]
NGS	• Genome-wide coverage • Multiple samples may be run in parallel • Promotes novel miRNA discovery • Can detect polymorphisms	• Complicated, non-standardized data analysis	[93–97]
Isothermal amplification	• No need for thermocycling equipment • Can improve existing qPCR, microarray, and NGS methods	• Disadvantages are technique-specific (see below)	[101]
• Exponential amplification	• High sensitivity	• May require a nicking enzyme, which complicates primer design	[102, 103]
• Rolling circle amplification	• 1 primer • Can be optimized for linear or exponential amplification	• Requires 2 enzymes (polymerase and ligase) • Initial denaturation not performed at room temperature	[105–109]
• Duplex-specific nuclease signal amplification	• High specificity	• Enzyme is not readily available	[110–113]
• Hybridization chain reaction	• No polymerase	• Linear amplification only	[114–120]
Near-infrared technology	• No autofluoresence • Minimal photobleaching • No tedious treatment of sample before or after the test	• Lanthanide probes are not yet commercially available and must be optimized	[132, 140–143]