410
H. Jin
limits on aptamer’s practical application. Unmodified aptamer like any other oligonucleotides generally survives about 5 min in blood and around 1 h in living cells [7,
8]. The survival time for aptamer decay in blood depending on its concentration and
conformational structure.
The body temperature (37 °C) may also be an additional interference parameter
for the bioactivity of aptamer in vivo. Higher temperatures disrupt the secondary and
tertiary structures of aptamer, which will disturb aptamer-target binding behavior
and accelerate aptamer degradation by nucleases.
The specificity and binding affinity are other challenges for aptamer selection. To
keep its specificity, aptamer requires purified target molecules during the SELEX
procedure, sometimes purified proteins are difficult to acquire due to their chemical
properties. Under certain circumstances, aptamers generated against target proteins
expressed in prokaryotic cells do not interact with the same proteins expressed in
eukaryotic cells due to post-translational modifications [9]. Aptamer cross reactivity
with its analog can be another obstacle for their clinical application due to the possible
side effects or even off-target binding because of the aptamer’s unspecific interaction
with other proteins.
Although aptamer presents a bunch of merits as a promising tool in all kinds of
clinical application scenarios, its inherent characteristics still pose a huge challenge
for widening its clinical application in the future.
14.3 The Scenario for Aptamers in Medical Application
14.3.1 Point-of-Care Tests
Accurate,simple, and rapid medical care is always the ultimate demand for clinical. Point-of-care tests (POCTs) is promising diagnostic technologies in in vitro
diagnostics (IVD) fields, which is essential for the identification and treatment of
many diseases, including chronical infection and terminal disease. POCTs are especially useful in limited-resource or non-existent healthcare setting or home healthcare
monitoring of chronical disease. The global market for POCTs is projected to reach
USD 46.7 billion by 2024 from USD 28.5 billion in 2019 [10]. At present, it is mainly
focusing on diabetes monitoring [11, 12], cardiometabolic monitoring [13], infectious disease testing [14], coagulation monitoring [15, 16], pregnancy and fertility
testing [17–19], tumor/cancer marker testing [20], fluid test, e.g., urinalysis [21, 22],
cholesterol [23, 24], and hematology [25, 26]
Among the detection methods, biosensors play a dominant role; they consists of
biorecognition element and signal transduction element which enable to bind with
its target and convert the binding event into a detectable signal with high affinity
and selectivity. The next generation of POCTs diagnostic is focused on the development of portable smart devices towards personalized healthcare monitoring and
management [27, 28], compared with traditional antibody, aptamers have favorable
H. Jin
limits on aptamer’s practical application. Unmodified aptamer like any other oligonucleotides generally survives about 5 min in blood and around 1 h in living cells [7,
8]. The survival time for aptamer decay in blood depending on its concentration and
conformational structure.
The body temperature (37 °C) may also be an additional interference parameter
for the bioactivity of aptamer in vivo. Higher temperatures disrupt the secondary and
tertiary structures of aptamer, which will disturb aptamer-target binding behavior
and accelerate aptamer degradation by nucleases.
The specificity and binding affinity are other challenges for aptamer selection. To
keep its specificity, aptamer requires purified target molecules during the SELEX
procedure, sometimes purified proteins are difficult to acquire due to their chemical
properties. Under certain circumstances, aptamers generated against target proteins
expressed in prokaryotic cells do not interact with the same proteins expressed in
eukaryotic cells due to post-translational modifications [9]. Aptamer cross reactivity
with its analog can be another obstacle for their clinical application due to the possible
side effects or even off-target binding because of the aptamer’s unspecific interaction
with other proteins.
Although aptamer presents a bunch of merits as a promising tool in all kinds of
clinical application scenarios, its inherent characteristics still pose a huge challenge
for widening its clinical application in the future.
14.3 The Scenario for Aptamers in Medical Application
14.3.1 Point-of-Care Tests
Accurate,simple, and rapid medical care is always the ultimate demand for clinical. Point-of-care tests (POCTs) is promising diagnostic technologies in in vitro
diagnostics (IVD) fields, which is essential for the identification and treatment of
many diseases, including chronical infection and terminal disease. POCTs are especially useful in limited-resource or non-existent healthcare setting or home healthcare
monitoring of chronical disease. The global market for POCTs is projected to reach
USD 46.7 billion by 2024 from USD 28.5 billion in 2019 [10]. At present, it is mainly
focusing on diabetes monitoring [11, 12], cardiometabolic monitoring [13], infectious disease testing [14], coagulation monitoring [15, 16], pregnancy and fertility
testing [17–19], tumor/cancer marker testing [20], fluid test, e.g., urinalysis [21, 22],
cholesterol [23, 24], and hematology [25, 26]
Among the detection methods, biosensors play a dominant role; they consists of
biorecognition element and signal transduction element which enable to bind with
its target and convert the binding event into a detectable signal with high affinity
and selectivity. The next generation of POCTs diagnostic is focused on the development of portable smart devices towards personalized healthcare monitoring and
management [27, 28], compared with traditional antibody, aptamers have favorable