Electroanalysis,
Journal Year:
2023,
Volume and Issue:
36(2)
Published: Dec. 6, 2023
Abstract
The
co‐precipitation
approach
was
employed
in
this
study
to
create
Fe
doped
ZnO
(Fe‐ZnO)
nanoparticles
(NPs).
To
characterize
the
synthesized
NPs,
Ultra
violet‐Visible
(UV‐Vis)
spectroscopy,
X‐ray
diffraction
(XRD),
fourier
transform
infrared
(FT‐IR),
scanning
electron
microscopy
(SEM),
and
Brunauer‐Emmett‐Teller
(BET)
were
used.
Here,
a
novel
electrochemical
for
detection
of
tryptophan
(Trp)
using
glassy
carbon
electrode
modified
with
Fe‐ZnO
NPs
(Fe‐ZnO/GCE)
is
demonstrated.
research
findings
revealed
that
Fe‐ZnO/GCE
enhanced
transfer
rate
Trp
oxidation.
sensitivity
phosphate
buffer
solution
(PBS)
at
pH
64.0
significantly
improved
compared
bare
GCE
due
electrocatalytic
activity
NPs.
exhibited
linear
response
concentrations
ranging
from
0.1
150
μM
limit
(LOD)
0.089
(3σ
/m
)
quantification
(LOQ)
about
0.3
(10σ
sweep
voltammetry
(LSV).
sensor
also
effectively
used
detect
African
catfish
multivitamin
tablets.
analysis
real
samples
good
recovery
values
89.60
99.15
%,
demonstrating
accuracy
practicality
method.
Scientific Reports,
Journal Year:
2025,
Volume and Issue:
15(1)
Published: Feb. 25, 2025
Accurate
measurement
of
tryptophan
(Trp)
levels
is
crucial
for
clinical
and
research
purposes,
such
as
nutritional
assessment,
disorder
diagnosis,
condition
management,
the
study
role
Trp
in
disease
pathophysiology.
Herein,
intercalation
1-octyl-3-methylimidazolium
chloride
[OMIM]+Cl−
ionic
liquids
(ILs)
between
layers
Ti3C2
MXenes
results
a
3D
porous
structure
with
large
active
surface
area
high
interlayer
spacing
(d-spacing).
Confined
[OMIM]+
ions
enhance
electroactive
sites
transfer
pathways
at
MXene
IL
interfaces
improve
electron
efficiency
oxidation,
improving
stability
via
strong
π‒π
electrostatic
MXene‒IL
interactions.
Under
optimal
conditions,
sensor
demonstrated
broad
detection
range
Trp,
ranging
from
0.001
to
240
µM,
low
limit
0.06
nM
(S/N
=
3).
Owing
its
exceptional
stability,
selectivity,
reproducibility,
proposed
IL-Ti3C2/GCE
exhibited
significant
potential
detecting
real
amino
acid
granules
urine
samples.
Heliyon,
Journal Year:
2023,
Volume and Issue:
9(6), P. e16627 - e16627
Published: May 24, 2023
The
main
objective
of
this
research
work
is
to
develop
a
low-cost
sensor
detect
l-tryptophan
(L-tryp)
in
real
sample
medium
based
on
modified
glassy
carbon
electrode.
For
this,
copper
oxide
nanoflowers
(CuONFs)
and
poly-l-glutamic
acid
(PGA)
were
used
modify
GCE.
prepared
NFs
PGA
coated
electrode
was
characterized
using
field
emission
scanning
electron
microscope
(FE-SEM)
with
energy
dispersive
X-ray
(EDX)
attenuated
total
reflectance
Fourier
transform
infrared
(ATR-FTIR)
spectroscopy.
Furthermore,
the
electrochemical
activity
performed
by
cyclic
voltammetry
(CV),
differential
pulse
(DPV)
impedance
spectroscopy
(EIS).
showed
excellent
electro-catalytic
towards
L-tryp
detection
PBS
solution
at
neutral
pH
7.0.
Based
physiological
condition,
proposed
can
concentration
linear
range
1.0
×
10-4-8.0
10-8
molL-1
having
limit
5.0
sensitivity
0.6μA/μMcm2.
selectivity
tested
mixture
salt
uric
above
conditions.
Finally,
strategy
demonstrated
recovery
value
analysis
like
milk
urine.
Food Reviews International,
Journal Year:
2024,
Volume and Issue:
40(10), P. 3869 - 3898
Published: July 26, 2024
Tryptophan
(Trp)
is
an
essential
amino
acid
required
by
the
body.
It
can
only
be
consumed
through
daily
food
intake.
Accurate
determination
of
Trp
in
and
biological
samples
was
crucial
for
safeguarding
human
health.
Fluorescence
analytical
technique
one
most
promising
methods
sensing
because
its
high
selectivity,
good
sensitivity
fast
response-time.
Most
current
reviews
lack
a
summary
detection
nutrients
such
as
Trp.
A
review
Trp-responsive
fluorescent
sensors
food,
pharmaceutical
(2017
onwards)
presented
this
paper.
The
fluorescence
mechanism,
sensor
types
practical
applications
these
were
discussed,
challenges
future
perspective
to
development
presented.
ChemistrySelect,
Journal Year:
2025,
Volume and Issue:
10(1)
Published: Jan. 1, 2025
Abstract
Electroanalysis
of
melatonin,
known
as
the
sleep
hormone,
in
presence
its
precursors,
L‐tryptophan
and
5‐hydroxy
tryptophan
biological
matrixes
is
an
attractive
research
topic.
The
interference
voltammetric
oxidation
signals
these
compounds,
which
have
similar
chemical
structures,
causes
their
determination
to
be
challenging.
This
project
aims
conduct
a
real‐time
electroanalysis
melatonin
precursors
samples
using
novel
nanocomposite
platform.
new
platform
incorporates
multi‐walled
carbon
nanotubes
(MWCNTs),
gold
nanoparticles
(GNPs),
graphitic
nitrides
(g‐C
3
N
4
)
placed
on
glassy
electrode
surface.
peak
can
effectively
separated
from
other
this
Thus,
easily
determined
electrochemically
precursors.
In
optimized
conditions,
electroanalytical
method
displayed
linear
response
range
between
5.0
×
10
−7
1.0
−5
mol/L
for
both
−8
−6
L‐tryptophan.
Furthermore,
proposed
modified
was
successfully
applied
determine
various
real
such
human
plasma,
urine,
pharmaceutical
formulations.
sensor
revealed
excellent
precision,
remarkable
simplicity,
acceptable
selectivity,
good
reproducibility,
long‐term
stability,
rapid
toward
L‐tryptophan,
matrixes.
