A brief review on Aptamer-based disease diagnosis in the livestock sector

Introduction 1. Aptamers synthesis technique

Aptamers are suitable substitutes for antibodies since they can be chemically synthesised and exhibit specificity equivalent to antibodies for antigen capture and identification (Thiviyanathan and Gorenstein, 2012) [58] . As a result, they are sometimes referred to as "synthetic antibodies" and have been in direct competition with antibodies in the study of disease detection, prevention, and treatment. They have benefits over antibodies, including lower price, smaller size, simplicity of manufacture and customization, and better stability (Song et al., 2008) [53] . In certain scenarios, aptamers are considered a better analog to monoclonal antibodies with respect to higher specificity, low immunogenicity and for simple in vitro selection (Niederlender, Fontaine and Karadjian, 2021) [41] . As a result, several aptamer-based systems in the form of biosensors (referred to as apta-sensors) have been created for the detection of pathogens and target analytes, immunophenotyping, and management of animal health. Accordingly apta-sensors also focus on the 'One Health' approach which benefits breeders, animal owners as well as the animals from both infectious and non-infectious diseases. Tuerk and Gold (1990) [59] provided a description of the traditional SELEX (Systematic Evolution of Ligands by Exponential Enrichment) technique. This approach produces aptamers that can last anywhere from a few weeks to a month. By using the same chemical process used to select aptamers and often used to hybridise primers during polymerase chain reaction (PCR), a library of oligonucleotides with distinctive but random sequences was created. The kind of the required aptamer is the only factor that influences several of the selection processes established during the traditional approach of SELEX (Fig. 1). Nucleicacid aptamers are receiving a lot of attention and have been used in a variety of contexts. The use of aptamers in the identification of human illnesses has been extensively studied; however there is very little information accessible in the field of veterinary medicine. As a result, the emphasis of this study will be on the use of aptamers in the diagnosis of animal illnesses, the detection of drug residues and pollutants, and the administration of targeted medication. There are various bacterial (e.g. mastitis, tuberculosis, enteritis or colibacillosis, tuberculosis etc.) and viral diseases (e. g. SARS CoV, influenza, FMD etc.) that have a high prevalence rate in animals and are affecting farmers' economies in many ways (Fig. 2). Other conditions, such as bovine spongiform encephalopathy (BSE), cancer, and toxins, play important roles in veterinary medicine in addition to infectious diseases.

Diagnosis of viral diseases 2.1 Influenza

Several aptamers have been reported to be effective in several viruses such as Muscovy duck parvovirus (Lu et al., 2018), highly pathogenic avian influenza (HPAI) A(H5) virus (Nguyen et al., 2017) [40] , H5N1 avian influenza virus (Wu et al., 2008), Triple reassortant influenza A virus (Wongphatcharachai et al., 2013) [64] etc.

Severe acute respiratory syndrome corona virus (SARS-CoV)

The recent pandemics and epizootics in various parts of the world have highlighted the public health importance of viruses such COVID-

Foot and mouth disease (FMD)

FMD mainly affects the animals such as swine, cattle, goats, deer, and sheep. FMD affects extensive areas worldwide enlisted in the notifiable diseases to the World Organization for Animal Health. Since it was recognized as a significant epidemic disease in 16th century to yet it is a major global animal health problem (Longjam et al., 2011) [33] . FMD has caused numerous outbreaks in the US, UK and Asia including India. Owing to significant economic losses there is an urgent need to develop a fast and most unswerving test for the detection of FMD virus. In order to detect this disease, DNA aptamers were successfully screened (Vidic et al., 2017) [61] . Ellingham et al., 2006 [13] reported the use of anti-3D pol aptamers that successfully inhibited the activity of RNA dependent RNA polymerase from FMD.

Rabies

Rabies is considered to be one of the most deadly viral infectious zoonotic diseases affecting CNS and becomes 100% fatal when the symptoms begin to appear, as reported by WHO. The causative agent responsible for the transmission of rabies from infected dogs to humans is an unsegmented negative sense RNA rabies virus (RABV). It belongs to the Lyssavirus of the Rhabdoviridae family. Both humans and animals are the victims of this virus mainly propagated via saliva or through direct contact with mucosa mainly open wounds, mouth, and eyes. According to WHO reports in 2023, India accounts for almost 36% of the world's deaths due to the rabies virus. The frequent victims of the RABV are children between the ages of 5 and 14 years. Liang et al., 2014 [31] successfully generated a ssDNA, GE54 aptamer against the RABV cultured in baby hamster kidney (BHK)-21 cells. The GE54 aptamer significantly protected healthy cells from the replication of RABV both in vitro and in vivo. Another class of DNA aptamers, the F021 and F024 acted on RABV most effectively than GE54 due to their ability of binding with more number of targeted molecules (Liang et al., 2014) [31] . [46] . Cheng et al. (2016) [7] developed aptamercoated magnetic beads and antibiotic-capped gold nanoclusters for the detection of bacteria. Baumstummler et al., 2014 [2] identified SOMAmer (slow off-rate modified aptamer) to detect S. aureus. SOMAmers are made from ssDNA that contain pyrimidine residues and have quite long (>30 min) dissociation rates (Gold et al., 2010). They found that SpA and Clf ASOMAmers are useful for the selective detection of S. aureus. Another study used ELONA (Enzyme-Linked Oligo Nucleotide Assay) to detect the Protein A-binding aptamer PA#2/8 in S. aureus (Stoltenburg et al., 2016) [56] .

Tuberculosis

Bovine tuberculosis (BT) is a slow progressing disease and primarily caused by the Mycobacterium bovis (M. bovis), and to a lesser extent by M. caprae and M. tuberculosis. M. bovis also causes arthritis, mastitis and respiratory diseases in cattle. Serological detection of M. bovis has been a concern due to compromised conventional approach. Fu et al., 2014 designed a single stranded-DNA (ssDNA) aptamer WKB-14 that bound specifically to M. bovis in a competitive indirect enzyme linked aptamer assay (ELAA). Bovine tuberculosis is affecting the livelihoods and is hampering efforts to control and/ or elimination by 2030 (Cousins, 2018) [8] . The traditional diagnostic test i.e. tuberculin skin test, is a standard and the most popular test in the livestock. However, the bacterial culture of M. bovis is a timeconsuming process and can take eight weeks or more. Aptamers are hopeful tools for developing POC diagnostic assays for TB. Mozioglu et al., 2016 [38] developed ssDNA aptamers that recognize M. tuberculosis H37Ra using SELEX procedure. Bovine tuberculosis caused by M. tuberculosis is difficult to be identified by the pathological symptoms. Release of bovine interferon gamma (BoIFN-c) by T-cells can offer a diagnostic marker of M. tuberculosis (Crulhas et al., 2017) [9] . Li et al., 2018 reported a voltammetric apta-sensor for detecting ESAT-6, a secretory antigen secreted by Mycobacterium Tuberculosis.

E. coli

Escherichia coli is ubiquitously found bacterial species in the intestinal gut flora of animals and can survive in multiple abiotic environments (Marton et al., 2016) [36] . E. coli benefits the host after colonizing the infant's gastrointestinal tract. Still, it may become a potent diseasecausing pathogen due to its virulence factors and ability to adapt to different niches causing high mortality (Kaper, Nataro, Mobley, 2004) [26] . Based on the type of disease intestinal pathogenic E. coli can be classified into enterohemorrhagic (EHEC), diffusely adherent (DAEC), entero-pathogenic (EPEC), and entero-invasive E. coli (EIEC). Various aptamers were reported to bind against specific E. coli species and are tabulated below: Enter Toxigenic E. coli (ETEC) K88 Aptamer B12 Peng et al., 2014 [44]

3.

E. coli NSM59 EcA5-27 Savory et al., 2014 [45]

4.

E. coli KCTC 2571 E2 SSDNA aptamer Kim et al., 2013 [28]

5.

E. coli ATCC 25922 P12-55 SSDNA aptamer Marton et al., 2016 [36] 6.

E. coli O157:H7 E1 Zhang et al., 2019 [70] 7.

E. coli O157:H7 E18R SSDNA aptamer Siddiqui and Yuan, 2021 [49] Wei et al., 2018 reported a user-friendly multifunctional spin chip that allows quantitative detection of E.coli using nanoparticle-based aptamer recognition. Aptamer binding Microchip capillary electrophoresis method was used for the detection of E. coli O157:H7 by coupling with laser-induced fluorescence (Zhang et al., 2019) [70] .

Diagnosis of Parasitic diseases

Protozoan parasite infections are a major global health issue, particularly in developing countries, due to poor sanitation and weak immune systems. Current diagnostic methods, like microscopic observation, immune detection, and PCR, are effective but limited by their time-consuming nature, need for cryogenic storage, and specialized equipment, which are scarce in remote areas. Research is now focusing on new diagnostic targets, with aptamers emerging as a promising tool. Aptamers are the synthetic molecules that bind specifically to targets, offer advantages such as stability and ease of production, potentially overcoming the limitations of existing diagnostic techniques. Researchers have expressed significant concern regarding the application of aptamers in the detection of parasitic diseases. Initially, a sandwich model of aptasensors (Ikebukuro, Kiyohara and Sode, 2004) [23] with an electrochemical variant was developed to detect parasites, utilizing"signal-on" architecture. "Initiated for detecting various parasitic organisms, electrochemical aptasensors successfully recognized only a few species." [42] reported the use of the rapid and costefficient paper-based analytical device (μPAD) to detect the malarial biomarker: recombinant Plasmodium falciparum lactate dehydrogenase rPfLDH using surface immobilized aptamers. Plasmodium lactate dehydrogenase (PLDH) is a valuable malaria biomarker due to its high expression in Plasmodium cells, significant structural and kinetic differences from human enzymes, and unique amino acid sequences across Plasmodium species, enabling precise species identification within different samples (Jain et al., 2014) [24] . Frith et al., 2018 [14] reported that rLDH7 aptamer has a 40nM dissociation constant (Kd) for the binding interaction with rPfLDH using microplate ELONAs. APTEC sensors combined with rLDH7 aptamer gave a higher detection limit of 16.6 nM than Malstat-based PLDH capture assays (Ogunmolasuyi et al., 2022) [42] . [24,21] .

Malaria by Plasmodium falciparum

Leishmaniasis

Leishmaniasis, a major tropical disease caused by Leishmania protozoa, is prevalent in Asia, Africa, and Central America. [37] employed an aptasensor approach to detect the Leishmania Infantum kinetoplastid membrane protein 11 (LiKMP-11). These findings underscore the diverse applications of aptamers in advancing diagnostic methods for Leishmaniasis.

Diagnosis of cancer

Cancer is a significant public health issue and the second leading cause of death globally. The incidence of new cancer cases is expected to rise quickly due to population growth and ongoing lifestyle choices that elevate cancer risk (Siegel, Miller, and Jemal, 2018) [50] . Hussain and Nguyen, 2014 emphasize that prioritizing early cancer detection and precise staging is just as vital as developing new anticancer medications and treatments for curing the disease. Aptamers have recently become promising molecular probes for enhancing the specificity and accuracy of cancer diagnostics and therapeutics due to their unique properties. Therefore, integrating aptamer-based technologies with physical or chemical diagnostic agents could significantly advance cancer detection (Kim et al., 2018) [27] . Cell membrane proteins like HER2 are often over expressed in various cancers, leading to poor prognosis, suboptimal treatment outcomes, and lower survival rates. Numerous HER2targeted drugs have been developed to treat tumors with high HER2 expression, effectively reducing HER2 levels. HER2-targeting DNA aptamers, known as Heraptamers, were labeled with 18F and evaluated both in vitro and in vivo for positron emission tomography (PET) imaging of HER2 in ovarian cancer (Zhu et al., 2017) [70] . Chi-hong et al., 2003 [66] ; Thiel et al., 2012 [57] ; also reported Heraptamers for detecting HER2 expression in several cancers. Several aptamers, including SYL3C (Song et al., 2013) [54] , TuTu22 (Wang et al., 2014) [62] , EpCAM (Xiang et al., 2015), Td05 (Ho et al., 2015), sgc8-c (Sicco et al., 2020) [66] , and AS1411 (Fu & Xiang, 2021) [67] , have been identified to bind to various molecular targets on cancer cells. Aptamer-based techniques for analyzing cancer cells are recognizing the molecular targets and capturing cancer cells, imaging and regulating membrane proteins with aptamers, and using aptamer-based probes for bioimaging at the subcellular level. Zeng, Tung and Zu, 2014 [69] developed a cancer cell-activatable probe by linking aptamers with paired fluorochrome-quencher molecules for a one-step assay of circulating tumor cells (CTCs), offering a valuable index for assessing tumor progression. Du, Peng and Li, 2019 [12] developed a lysosome-targeting framework nucleic acid (FNA) nanodevice that incorporates an i-motif and an adenosine triphosphate (ATP)-binding aptamer (ABA) into a DNA triangular prism. This nanodevice undergoes a conformational switch upon entering the lysosomal compartment of cancer cells, producing fluorescence to indicate abnormal pH and ATP levels, enabling dynamic imaging of the lysosomal environment.

Conclusion

Aptamer-based diagnostic methods have become increasingly promising in contemporary laboratories.

Research across biomedical fields like bacteria and viruses, requires the help of aptamers in evaluating drug effectiveness, disease diagnosis, and therapy. SELEXderived technologies facilitate innovative detection, diagnostic, and treatment methods, which are increasingly recognized for their advantages as alternatives or complementary to antibody reagents (Chen et al., 2022) [6] .

Aptamers have shown significant potential by enhancing existing detection methods and serving as novel biosensors for imaging and detecting cancer cells (Zhou et al., 2017; Li et al., 2014) [71] . Furthermore, there is a crucial need to expand the detection capabilities of aptamer visualization.

Accelerating the application of nucleic acid aptamers in disease detection, precise diagnosis, and treatment is essential (Ospina-Villa et al., 2016) [43] . It is crucial to advance ongoing research by optimizing the existing aptamers and prioritizing the development of new aptamers targeting novel molecular targets. Therefore, the aptamerbased technologies discussed in this review contribute comprehensive insights into viral, bacterial, protozoan, and cancer disease diagnosis.

References

1. Banal BK, Gupta DK. Economic analysis of bovine mastitis in India and Punjab-A review. Indian J Dairy Sci. 2009;62(5):337-345.
2. Baumstummler A, Lehmann D, Janjic N, Ochsner UA. Specific capture and detection of Staphylococcus aureus with high-affinity modified aptamers to cell surface components. Lett Appl Microbiol. 2014;59(4):422-431.
3. Bruno JG, Richarte AM, Savage AA, Sivils JC. Development and Characterization of DNA Aptamers Which Bind Kinesins from Leishmania Promastigotes. J Bionanoscience. 2014;8(3):195-206.
4. Burza S, Croft SL, Boelaert M. Leishmaniasis. Lancet. 2018;392(10151):951-970.
5. Chen CHB, Chernis GA, Hoang VQ, Landgraf R. Inhibition of heregulin signaling by an aptamer that preferentially binds to the oligomeric form of human epidermal growth factor receptor-3. Proc Natl Acad Sci. 2003;100(16):9226-9231.
6. Chen J, Zhou J, Peng Y, Xie Y, Xiao Y. Aptamers: A prospective tool for infectious diseases diagnosis. J Clin Lab Anal. 2022;36(11):e24725.
7. Cheng D, Yu M, Fu F, Han W, Li G, Xie J, et al. Dual recognition strategy for specific and sensitive detection of bacteria using aptamer-coated magnetic beads and antibiotic-capped gold nanoclusters. Anal Chem. 2016;88(1):820-825.
8. Cousins S. The challenges of preventing bovine tuberculosis. Bull World Health Organ. 2018, 96(2).
9. Crulhas BP, Hadley D, Liu Y, Shin DS, Stybayeva G, Imanbekova M, et al. An electrochemical aptasensor for detection of bovine interferon gamma. Anal Methods. 2017;9(31):4527-4532.
10. Dalrymple U, Arambepola R, Gething PW, Cameron E. How long do rapid diagnostic tests remain positive after anti-malarial treatment? Malar J. 2018;17:1-13.
11. de Araujo FF, Nagarkatti R, Gupta C, Marino AP, Debrabant A. Aptamer-based detection of disease biomarkers in mouse models for Chagas drug discovery. PLoS Negl Trop Dis. 2015;9(1):e3451.
12. Du Y, Peng P, Li T. DNA logic operations in living cells utilizing lysosome-recognizing framework nucleic acid nanodevices for subcellular imaging. ACS Nano. 2019;13(5):5778-5784.
13. Ellingham M, Bunka DH, Rowlands DJ, Stonehouse NJ. Selection and characterization of RNA aptamers to the RNA-dependent RNA polymerase from foot-andmouth disease virus. RNA. 2006;12(11):1970-1979.
14. Frith KA, Fogel R, Goldring JD, Krause RG, Khati M, Hoppe H, et al. Towards development of aptamers that specifically bind to lactate dehydrogenase of Plasmodium falciparum through epitopic targeting. Malar J. 2018;17:1-16.
15. Fu P, Sun Z, Yu Z, Zhang Y, Shen J, Zhang H, et al. Enzyme linked aptamer assay: based on a competition format for sensitive detection of antibodies to Mycoplasma bovis in serum. Anal Chem. 2014;86(3):1701-1709.
16. Fu Z, Xiang J. Aptamers, the nucleic acid antibodies, in cancer therapy. Adv Med Biochem. Genomics, Physiol, Pathol. 2021;143-175.
17. Gold L, Ayers D, Bertino J, Bock C, Bock A, Brody E, et al. Aptamer-based multiplexed proteomic technology for biomarker discovery. Nat Preced. 2010:1-1.
18. González VM, Martín ME, Fernández G, GarcíaSacristán A. Use of aptamers as diagnostics tools and antiviral agents for human viruses. Pharmaceutics. 2016;9(4):78.
19. Gu MB. Highly sensitive detection of pandemic viruses, biomarkers, and small molecules by using aptamer nanobiosensors. Nanomedicine. 2016;12(2):452-452.
20. Ho LC, Wu WC, Chang CY, Hsieh HH, Lee CH, Chang HT. Aptamer-conjugated polymeric nanoparticles for the detection of cancer cells through "turn-on" retro-self-quenched fluorescence. Anal Chem. 2015;87(9):4925-4932.
21. Howard RJ, Uni S, Aikawa M, Aley SB, Leech JH, Lew AM, et al. Secretion of a malarial histidine-rich protein (Pf HRP II) from Plasmodium falciparuminfected erythrocytes. J Cell Biol. 1986;103(4):12691277.
22. Hussain T, Nguyen QT. Molecular imaging for cancer diagnosis and surgery. Adv Drug Deliv Rev. 2014;66:90-100.
23. Ikebukuro K, Kiyohara C, Sode K. Electrochemical detection of protein using a double aptamer sandwich. Anal Lett. 2004;37(14):2901-2909.
24. Jain P, Chakma B, Patra S, Goswami P. Potential biomarkers and their applications for rapid and reliable detection of malaria. Biomed Res Int. 2014;2014(1):852645.
25. Kanwar JR, Roy K, Kanwar RK. Chimeric aptamers in cancer cell-targeted drug delivery. Crit Rev Biochem Mol Biol. 2011;46(6):459-477.
26. Kaper JB, Nataro JP, Mobley HL. Pathogenic Escherichia coli. Nat Rev Microbiol. 2004;2(2):123140.
27. Kim M, Kim DM, Kim KS, Jung W, Kim DE. Applications of cancer cell-specific aptamers in targeted delivery of anticancer therapeutic agents. Molecules. 2018;23(4):830.
28. Kim YS, Song MY, Jurng J, Kim BC. Isolation and characterization of DNA aptamers against Escherichia coli using a bacterial cell-systematic evolution of ligands by exponential enrichment approach. Anal Biochem. 2013;436(1):22-28.
29. Li L, Yuan Y, Chen Y, Zhang P, Bai Y, Bai L. Aptamer based voltammetric biosensor for Mycobacterium tuberculosis antigen ESAT-6 using a nanohybrid material composed of reduced graphene oxide and a metal-organic framework. Microchim Acta. 2018;185:1-9.
30. Li X, Zhang W, Liu L, Zhu Z, Ouyang G, An Y, et al. In vitro selection of DNA aptamers for metastatic breast cancer cell recognition and tissue imaging. Anal Chem. 2014;86(13):6596-6603.
31. Liang HR, Hu GQ, Xue XH, Li L, Zheng XX, Gao YW, et al. Selection of an aptamer against rabies virus: a new class of molecules with antiviral activity. Virus Res. 2014;184:7-13.
32. Lo Y, Cheung YW, Wang L, Lee M, Figueroa-Miranda G, Liang S, et al. An electrochemical aptamer-based biosensor targeting Plasmodium falciparum histidinerich protein II for malaria diagnosis. Biosens Bioelectron. 2021;192:113472.
33. Longjam N, Deb R, Sarmah AK, Tayo T, Awachat VB, Saxena VK. A brief review on diagnosis of foot-andmouth disease of livestock: Conventional to molecular tools. Vet Med Int. 2011;2011(1):905768.
34. Lu R, Zhao X, Li J, Niu P, Yang B, Wu H, et al. Genomic characterization and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. Lancet. 2020;395(10224):565-574.
35. Lu T, Ma Q, Yan W, Wang Y, Zhang Y, Zhao L, Chen H. Selection of an aptamer against Muscovy duck parvovirus for highly sensitive rapid visual detection by label-free aptasensor. Talanta. 2018;176:214-220.
36. Marton S, Cleto F, Krieger MA, Cardoso J. Isolation of an aptamer that binds specifically to E. coli. PLoS One. 2016;11(4):e0153637.
37. Moreno M, González VM, Rincón E, Domingo A, Domínguez E. Aptasensor based on the selective electrodeposition of protein-linked gold nanoparticles on screen-printed electrodes. Analyst. 2011;136(9):1810-1815.
38. Mozioglu E, Gokmen O, Tamerler C, Kocagoz ZT, Akgoz M. Selection of nucleic acid aptamers specific for Mycobacterium tuberculosis. Appl Biochem Biotechnol. 2016;178:849-864.
39. Nataro JP, Kaper JB. Diarrheagenic Escherichia coli. Clin Microbiol Rev. 1998;11(1):142-201.
40. Nguyen DT, Jang Y, Nguyen TD, Jones J, Shepard SS, Yang H, et al. Shifting clade distribution, reassortment, and emergence of new subtypes of highly pathogenic avian influenza A (H5) viruses collected from Vietnamese poultry from 2012 to 2015. J Virol. 2017;91(5):10-1128.
41. Niederlender S, Fontaine JJ, Karadjian G. Potential applications of aptamers in veterinary science. Vet Res. 2021;52(1):79.
42. Ogunmolasuyi AM, Fogel R, Hoppe H, Goldring D, Limson J. A microfluidic paper analytical device using capture aptamers for the detection of Pf LDH in blood matrices. Malar J. 2022;21(1):174.
43. Ospina-Villa JD, Zamorano-Carrillo A, CastañónSánchez CA, Ramírez-Moreno E, Marchat LA. Aptamers as a promising approach for the control of parasitic diseases. Braz J Infect Dis. 2016;20:610-618.
44. Peng Z, Ling M, Ning Y, Deng L. Rapid fluorescent detection of Escherichia coli K88 based on DNA aptamer library as direct and specific reporter combined with immuno-magnetic separation. J Fluoresc. 2014;24:1159-1168.
45. Savory N, Nzakizwanayo J, Abe K, Yoshida W, Ferri S, Dedi C, et al. Selection of DNA aptamers against uropathogenic Escherichia coli NSM59 by quantitative PCR controlled Cell-SELEX. J Microbiol Methods. 2014;104:94-100.
46. Sharma N, Maiti SK. Prevalence and etiology of subclinical mastitis in cows. Indian J Vet Res. 2010, 19(2).
47. Shigdar S, Lin J, Yu Y, Pastuovic M, Wei M, Duan W. RNA aptamer against a cancer stem cell marker epithelial cell adhesion molecule. Cancer Sci. 2011;102(5):991-998.
48. Sicco E, Baez J, Ibarra M, Fernández M, Cabral P, Moreno M, et al. Sgc8-c aptamer as a potential theranostic agent for hemato-oncological malignancies. Cancer Biother Radiopharm. 2020;35(4):262-270.
49. Siddiqui S, Yuan J. Binding Characteristics Study of DNA based Aptamers for E. coli O157:H7. Molecules. 2021;26(1):204.
50. Siegel RL, Miller KD, Jemal A. Cancer statistics, 2018. CA Cancer J Clin. 2018;68(1):7-30.
51. Simmons SC, McKenzie EA, Harris LK, Aplin JD, Brenchley PE, Velasco-Garcia MN, Missailidis S. Development of novel single-stranded nucleic acid aptamers against the pro-angiogenic and metastatic enzyme heparanase (HPSE1). PLoS One. 2012;7(6):e37938.
52. Singh NK, Jain P, Das S, Goswami P. Dye coupled aptamer-captured enzyme catalyzed reaction for detection of Pan malaria and P. Falciparum species in laboratory settings and instrument-free paper-based platform. Anal Chem. 2019;91(6):4213-21.
53. Song S, Wang L, Li J, Fan C, Zhao J. Aptamer-based biosensors. TrAC Trends Anal Chem. 2008;27(2):10817.
54. Song Y, Zhu Z, An Y, Zhang W, Zhang H, Liu D, et al. Selection of DNA aptamers against epithelial cell adhesion molecule for cancer cell imaging and circulating tumor cell capture. Anal Chem. 2013;85(8):4141-9.
55. Steverding D. The history of leishmaniasis. Parasites Vectors. 2017;10:1-10.
56. Stoltenburg R, Krafčiková P, Víglaský V, Strehlitz B. G-quadruplex aptamer targeting Protein A and its capability to detect Staphylococcus aureus demonstrated by ELONA. Sci Rep. 2016;6(1):33812.
57. Thiel KW, Hernandez LI, Dassie JP, Thiel WH, Liu X, Stockdale KR, et al. Delivery of chemo-sensitizing siRNAs to HER2+-breast cancer cells using RNA aptamers. Nucleic Acids Res. 2012;40(13):6319-37.
58. Thiviyanathan V, Gorenstein DG. Aptamers and the next generation of diagnostic reagents. Proteomics Clin Appl. 2012;6(11-12):563-73.
59. Tuerk C, Gold L. Systematic evolution of ligands by exponential enrichment: RNA ligands to bacteriophage T4 DNA polymerase. Science. 1990;249(4968):505-10.
60. Ugah UI, Alo MN, Owolabi JO, Okata-Nwali OD, Ekejindu IM, Ibeh N, Elom MO. Evaluation of the utility value of three diagnostic methods in the detection of malaria parasites in endemic area. Malar J. 2017;16:1-8.
61. Vidic J, Manzano M, Chang CM, Jaffrezic-Renault N. Advanced biosensors for detection of pathogens related to livestock and poultry. Vet Res. 2017;48:1-22.
62. Wang DL, Song YL, Zhu Z, Li XL, Zou Y, Yang HT, et al. Selection of DNA aptamers against epidermal growth factor receptor with high affinity and specificity. Biochem Biophys Res Commun. 2014;453(4):681-5.
63. Wei X, Zhou W, Sanjay ST, Zhang J, Jin Q, Xu F, et al. Multiplexed instrument-free bar-chart spinchip integrated with nanoparticle-mediated magnetic aptasensors for visual quantitative detection of multiple pathogens. Anal Chem. 2018;90(16):9888-96.
64. Wongphatcharachai M, Wang P, Enomoto S, Webby RJ, Gramer MR, Amonsin A, Sreevatsan S. Neutralizing DNA aptamers against swine influenza H3N2 viruses. J Clin Microbiol. 2013;51(1):46-54.
65. Wu WL, Chen Y, Wang P, Song W, Lau SY, Rayner JM, et al. Antigenic profile of avian H5N1 viruses in Asia from 2002 to 2007. J Virol. 2008;82(4):1798-807.
66. Wu W, Zhang J, Zheng M, Zhong Y, Yang J, Zhao Y, et al. An aptamer-based biosensor for colorimetric detection of Escherichia coli O157:H7. PLoS One. 2012;7(11):e48999.
67. Xiang D, Zheng C, Zhou SF, Qiao S, Tran PH, Pu C, et al. Superior performance of aptamer in tumor penetration over antibody: implication of aptamer-based theranostics in solid tumors. Theranostics. 2015;5(10):1083.
68. Xu Y, Li X, Zhu B, Liang H, Fang C, Gong Y, et al. Characteristics of pediatric SARS-CoV-2 infection and potential evidence for persistent fecal viral shedding. Nat Med. 2020;26(4):502-5.
69. Zeng Z, Tung CH, Zu Y. A cancer cell-activatable aptamer-reporter system for one-step assay of circulating tumor cells. Mol Ther Nucleic Acids. 2014;3.
70. Zhang Y, Zhu L, He P, Zi F, Hu X, Wang Q. Sensitive assay of Escherichia coli in food samples by microchip capillary electrophoresis based on specific aptamer binding strategy. Talanta. 2019;197:284-90.
71. Zhou G, Latchoumanin O, Bagdesar M, Hebbard L, Duan W, Liddle C, et al. Aptamer-based therapeutic approaches to target cancer stem cells. Theranostics. 2017;7(16):3948.
72. Zhu G, Zhang H, Jacobson O, Wang Z, Chen H, Yang X, et al. Combinatorial screening of DNA aptamers for molecular imaging of HER2 in cancer. Bioconjug Chem. 2017;28(4):1068-75.