Aptamer-Based Strategies to Address Challenges in COVID-19 Diagnosis and Treatments

Table 3

List of high-affinity ssDNA and RNA aptamers targeting the S protein, RBD of the S protein, N protein, or ACE2 protein isolated using different SELEX protocols as potential therapeutic agents for COVID-19.

Target	Types	Aptamer sequence (5′-3′)	Randomization region length (bp)	KD (nM)	Partitioning method	Selection pool regeneration method	References
S Protein	ssDNA	GGG​AGA​GGA​GGG​AGA​TAG​ATA​TCA​ACC​CAT​GGT​AGG​TAT​TGC​TTG​GTA​GGG​ATA​GTG​GGC​TTG​ATG​TTT​CGT​GGA​TGC​CAC​AGG​AC	40	21 ± 4.6	Bead	Lambda exonuclease digestion	Schmitz et al. [7]
S Protein	ssDNA	ATC​CAG​AGT​GAC​GCA​GCA​TCG​AGT​GGC​TTG​TTT​GTA​ATG​TAG​GGT​TCC​GGT​CGT​GGG​TTG​GAC​ACG​GTG​GCT​TAG​T	40	28	Bead	—	Liu et al. [6]
SRBD	ssDNA	CGC​AGC​ACC​CAA​GAA​CAA​GGA​CTG​CTT​AGG​ATT​GCG​ATA​GGT​TCG​G	—	44.78 ± 9.97	Bead	—	Sun et al. [8]
SRBD	RNA	GAT​CCA​TGG​GCA​CTA​TTT​ATA​TCA​ACC​TCT​TCC​TGACG​GAA​GTA​TCG​GTC​CAG​GAA​TTA​CAA​ATG​TCG TTGGTGGCCC	36	∼18	Bead	RNA polymerase transcription	Valero et al. [9]
		ATC​CAG​AGT​GAC​GCA​GCA​ATT​TAC​CGA​TGG​CTT​GTT​TGT​AAT​GTA​GGG​TTC​CGT​CGG​ATT​GGA​CAC​GGT​GGC​TTA​GT		27
N protein	RNA	UGU​CGU​UCG​CUG​UCU​UGC​UAC​GUU​ACG​UUA​CAC​GGU​UGG	—	1.65 ± 0.41	—	—	Parashar et al. [3]
ACE2	ssDNA	ATA​GTC​CCT​GGC​GTG​CTT​GAC​AGC​AAC​ACG​AAC​ACT​GAA​CGT​TCT​TAA​CAA​GCC​TGG​CAG​AGC​AGG​TAC​GGT​GTC​A	40	33	Bead	Denaturation and rapid cooling	Villa et al. [10]
		ATA​GTC​CCT​GGC​GTG​CTT​CCG​CGA​GAG​TTC​GAC​ATT​CCC​GAA​AGT​ACG​ACG​AAA​GTC​CAG​AGC​AGG​TAC​GGT​GTC​A		47