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T. Zhang et al.
malaria, Ebola, Zika, human immunodeficiency virus (HIV), tuberculosis, hepatitis
and measles are not only considered as life-threatening concerns worldwide, but they
have also been declared as major causes of high mortalities and morbidities globally
[4–6].
Over the past decades, new pathogens, such as the severe acute respiratory
syndrome (SARS) [7–9], Ebola virus [10, 11] and SARS-CoV-2, have caused illness
associated with significant economic burdens [12]. Moreover, some pathogenic
microbes such as Staphylococcus aureus and Mycobacterium tuberculosis have been
found to develop resistance to antibiotics [13, 14]. This brought unprecedented
challenges to the diagnosis and therapeutics of infectious diseases.
Infectious diseases can be traditionally diagnosed by clinical features like the
length of incubation period, the characteristics of fever, rash, cough and so on [15].
The other diagnosis basis is epidemiological information, which includes the areas
of disease, season of onset, previous infectious diseases and contact history. The two
pathology diagnoses are frequent methods to diagnose infectious diseases and serve
as cytopathology materials, which can be used to follow the illnesses and monitor
the response to the treatment [16]. In laboratory tests, two diagnostic methods are
commonly adopted. Pathogen inspection is an analytical tool to confirm the diagnosis.
For example, Plasmodium, Microfilaria and other pathogens can be inspected under
the microscope. In addition, immunological examination is another specific diagnostic method extensively selected in clinical examination. However, these methods
are complicated to operate and require a long time.
Molecular detection, as a new precise and specific detection method, shows a
brilliant prospect in the diagnosis of infectious diseases, among which nucleic acidbased assay is favored by scholars because of its high efficiency, sensitivity and
specificity [17]. In nucleic acid-based diagnosis, traditional amplification methods
including PCR, nucleic acid sequence-based amplification (NASBA), loop-mediated
isothermal amplification (LAMP), rolling circle amplification (RCA) and multiplex
ligation-dependent probe amplification have been adapted to construct assays for
infectious diseases [18, 19]. However, these methods also require nucleic acid extraction and precise time-control equipment, resulting in a relatively long operation time
and high price cost.
Aptamers are short single-strand sequences of either DNA or RNA molecules,
which are identified in vitro through a systematic evolution of ligands by exponential
enrichment (SELEX) process [20]. As molecular ligands, aptamers have the same
feature to specifically bind with targets as antibodies. Meanwhile, aptamers are highly
programmable, stable, cost-effective and easy-to-obtain, which suggests that they
can serve as potent diagnostic agents in infectious diseases [21]. Aptamers can be
screened for identifying pathogens and disease-related biomarker such as toxin and
antigen and the application of aptamers can potentially make remarkable strides
toward infectious diseases diagnosis.
In this chapter, we will present the basic features of most prevalent infectious
diseases and the efforts to obtain aptamers against their pathogen counterparts. Then,
we will discuss the design strategies and working principles of typical aptasensors, nanomaterial-involved aptasensors and microfluidics-integrated aptasensors
T. Zhang et al.
malaria, Ebola, Zika, human immunodeficiency virus (HIV), tuberculosis, hepatitis
and measles are not only considered as life-threatening concerns worldwide, but they
have also been declared as major causes of high mortalities and morbidities globally
[4–6].
Over the past decades, new pathogens, such as the severe acute respiratory
syndrome (SARS) [7–9], Ebola virus [10, 11] and SARS-CoV-2, have caused illness
associated with significant economic burdens [12]. Moreover, some pathogenic
microbes such as Staphylococcus aureus and Mycobacterium tuberculosis have been
found to develop resistance to antibiotics [13, 14]. This brought unprecedented
challenges to the diagnosis and therapeutics of infectious diseases.
Infectious diseases can be traditionally diagnosed by clinical features like the
length of incubation period, the characteristics of fever, rash, cough and so on [15].
The other diagnosis basis is epidemiological information, which includes the areas
of disease, season of onset, previous infectious diseases and contact history. The two
pathology diagnoses are frequent methods to diagnose infectious diseases and serve
as cytopathology materials, which can be used to follow the illnesses and monitor
the response to the treatment [16]. In laboratory tests, two diagnostic methods are
commonly adopted. Pathogen inspection is an analytical tool to confirm the diagnosis.
For example, Plasmodium, Microfilaria and other pathogens can be inspected under
the microscope. In addition, immunological examination is another specific diagnostic method extensively selected in clinical examination. However, these methods
are complicated to operate and require a long time.
Molecular detection, as a new precise and specific detection method, shows a
brilliant prospect in the diagnosis of infectious diseases, among which nucleic acidbased assay is favored by scholars because of its high efficiency, sensitivity and
specificity [17]. In nucleic acid-based diagnosis, traditional amplification methods
including PCR, nucleic acid sequence-based amplification (NASBA), loop-mediated
isothermal amplification (LAMP), rolling circle amplification (RCA) and multiplex
ligation-dependent probe amplification have been adapted to construct assays for
infectious diseases [18, 19]. However, these methods also require nucleic acid extraction and precise time-control equipment, resulting in a relatively long operation time
and high price cost.
Aptamers are short single-strand sequences of either DNA or RNA molecules,
which are identified in vitro through a systematic evolution of ligands by exponential
enrichment (SELEX) process [20]. As molecular ligands, aptamers have the same
feature to specifically bind with targets as antibodies. Meanwhile, aptamers are highly
programmable, stable, cost-effective and easy-to-obtain, which suggests that they
can serve as potent diagnostic agents in infectious diseases [21]. Aptamers can be
screened for identifying pathogens and disease-related biomarker such as toxin and
antigen and the application of aptamers can potentially make remarkable strides
toward infectious diseases diagnosis.
In this chapter, we will present the basic features of most prevalent infectious
diseases and the efforts to obtain aptamers against their pathogen counterparts. Then,
we will discuss the design strategies and working principles of typical aptasensors, nanomaterial-involved aptasensors and microfluidics-integrated aptasensors