11 Hormone Aptamers in Endocrine-Related Diseases
329
Except for P4G13, Marinella G. Sandros group developed another specific Xaptamers for progesterone, named X-aptamer 5, with a KD of 25.58 pM. They
employed nano-enhancers (NIR quantum dots) as special signal amplification probes
to generate a detection limit of 1.575 ng/mL (5 nM) of progesterone [22, 35]. This
aptamer provides more possibilities for the application of P4 detection in future
clinical scenarios.
11.2.3 Insulin-Related Aptamers
Insulin is a peptide hormone secreted by the β cells of the pancreatic islets of Langerhans. It maintains normal blood glucose levels by facilitating cellular glucose uptake,
regulating carbohydrate, lipid and protein metabolism, and promoting cell division
and growth through its mitogenic effects [36]. The level of insulin has been proved
to be one of the most critical indicators for the function of endocrine beta cells [37].
Abnormal level of insulin has been associated with various diseases such as diabetes,
cancers, neurodegenerative diseases, and other related diseases. Monitoring of variations of insulin is critical in clinical diagnosis, disease surveillance, and follow-up
treatment, it is significant to find a simple and rapid method to detect insulin in biological fluid [38]. Aptamer- based sensors for insulin detection are popularly studied all
over the world. Most of the aptasensors are based on the IGA3, an insulin aptamer
selected by Japanese researchers in 2009 [25].
In 2013, Lai et al. [26] developed an electrochemical-aptamer-based(E-AB) sensor
using insulin-linked polymorphic region (ILPR) [39] sequence as an aptamer, this
28 mer naturally occurring aptamer located at the human insulin promoter and could
form an intramolecular G-quartet structure, controlling the insulin gene expression.
These sensors react with insulin in a concentration-dependent manner, achieving a
really low detection limit of 10 nM. This strategy broadens the possibility to obtain
a suitable aptamer by targeting related regulatory molecules as well.
In 2017, AmouzadehTabrizigroup [40] designed a dual-signal electrochemical
insulin aptasensor. Researchers used methylene blue (MB)-modified insulin-binding
aptamer (IBA) as a “signal-off” probe and DNA2/redox reporter (Fc) co-modified
gold nanoparticles (DNA2Fc@GNPs) as the “signal-on” probe. The “signal-off”
probe and the “signal-on” probe are integrated by the linker mDNA [40]. The
detectable lowest concentration was 0.1 pM.
In 2019, Muhammand et al. [41] designed a nano-aptasensor that can detect human
serum glucose and insulin levels simultaneously. The aptasensor was constructed
based on the static quenching and the inner filter effect of CdTe/CdS/ZnS quantum
dots and carbon dots. The linear ranges of insulin and glucose were 0.2–2 nM and 0.5–
7 mM, and the limits of detection for insulin and glucose were 0.018 nM and 0.058
mM, respectively. This aptamer-based detection works similarly in either human
serum or working solutions, and the aptasensor provides the possibility to detect
multiple markers for single POCT of clinical scenarios.
329
Except for P4G13, Marinella G. Sandros group developed another specific Xaptamers for progesterone, named X-aptamer 5, with a KD of 25.58 pM. They
employed nano-enhancers (NIR quantum dots) as special signal amplification probes
to generate a detection limit of 1.575 ng/mL (5 nM) of progesterone [22, 35]. This
aptamer provides more possibilities for the application of P4 detection in future
clinical scenarios.
11.2.3 Insulin-Related Aptamers
Insulin is a peptide hormone secreted by the β cells of the pancreatic islets of Langerhans. It maintains normal blood glucose levels by facilitating cellular glucose uptake,
regulating carbohydrate, lipid and protein metabolism, and promoting cell division
and growth through its mitogenic effects [36]. The level of insulin has been proved
to be one of the most critical indicators for the function of endocrine beta cells [37].
Abnormal level of insulin has been associated with various diseases such as diabetes,
cancers, neurodegenerative diseases, and other related diseases. Monitoring of variations of insulin is critical in clinical diagnosis, disease surveillance, and follow-up
treatment, it is significant to find a simple and rapid method to detect insulin in biological fluid [38]. Aptamer- based sensors for insulin detection are popularly studied all
over the world. Most of the aptasensors are based on the IGA3, an insulin aptamer
selected by Japanese researchers in 2009 [25].
In 2013, Lai et al. [26] developed an electrochemical-aptamer-based(E-AB) sensor
using insulin-linked polymorphic region (ILPR) [39] sequence as an aptamer, this
28 mer naturally occurring aptamer located at the human insulin promoter and could
form an intramolecular G-quartet structure, controlling the insulin gene expression.
These sensors react with insulin in a concentration-dependent manner, achieving a
really low detection limit of 10 nM. This strategy broadens the possibility to obtain
a suitable aptamer by targeting related regulatory molecules as well.
In 2017, AmouzadehTabrizigroup [40] designed a dual-signal electrochemical
insulin aptasensor. Researchers used methylene blue (MB)-modified insulin-binding
aptamer (IBA) as a “signal-off” probe and DNA2/redox reporter (Fc) co-modified
gold nanoparticles (DNA2Fc@GNPs) as the “signal-on” probe. The “signal-off”
probe and the “signal-on” probe are integrated by the linker mDNA [40]. The
detectable lowest concentration was 0.1 pM.
In 2019, Muhammand et al. [41] designed a nano-aptasensor that can detect human
serum glucose and insulin levels simultaneously. The aptasensor was constructed
based on the static quenching and the inner filter effect of CdTe/CdS/ZnS quantum
dots and carbon dots. The linear ranges of insulin and glucose were 0.2–2 nM and 0.5–
7 mM, and the limits of detection for insulin and glucose were 0.018 nM and 0.058
mM, respectively. This aptamer-based detection works similarly in either human
serum or working solutions, and the aptasensor provides the possibility to detect
multiple markers for single POCT of clinical scenarios.