Analytical Methods,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 13, 2024
In
this
work,
we
have
explored
the
metal
ion
sensing
properties
of
two
bisbenzimidazole-based
fluorescent
probes,
that
differ
in
their
conformational
flexibility,
an
aqueous
medium.
The
compound
with
a
flexible
methyl
spacer
(1)
experienced
blue
shifts
its
absorption
and
emission
maxima
(along
turn-off
response)
upon
addition
Hg2+
ions.
On
contrary,
relatively
rigid
structure
(2)
showed
red
both
when
treated
under
similar
conditions.
Detailed
mechanistic
studies
indicated
1
formed
:
2
complex
ions,
where
pyridine
nitrogen
ends
benzimidazole
units
are
involved
coordination.
However,
for
2,
binding
stoichiometry
changed
to
ions
remained
connected
only
through
ends.
Not
did
changes
molecular
level
interactions
alter
optical
response,
but
they
also
altered
efficacy
sensing;
degree
response
was
more
prominent
than
2.
Also,
it
observed
could
dissociate
preformed
aggregated
structures
1,
while
case
promotes
aggregate
formation.
sensor
further
utilized
analysis
real-life
water
samples
detection
intracellular
conditions
(HeLa
cells).
Langmuir,
Год журнала:
2024,
Номер
40(21), С. 10966 - 10979
Опубликована: Май 15, 2024
Suitable
functional
group-engineered
π-conjugated
aromatic
dimides
based
on
perylene
(PDI)
and
naphthyl
scaffolds
(NDI)
demonstrated
excellent
sensitivity
toward
different
gaseous
analytes.
However,
to
date,
no
methodical
analysis
has
been
performed
rationalize
molecular-level
interactions
in
the
context
of
optical
transduction,
which
is
essential
for
systematic
performance
optimization
NDI/PDI-based
molecular
sensors.
Therefore,
this
present
work,
NDI/PDI
have
designed
with
amino
acid
groups
(alanine,
ALA
glutamic
acid,
GLU)
at
terminal
positions,
we
subsequently
compared
efficacy
four
imide
derivatives
as
model
hosts
hydrazine
adsorption.
Specifically,
adsorption
interaction
sites
thoroughly
investigated
using
ab
initio
calculations,
where
energy,
charge
transfer,
recovery
time
emphasized.
Theoretical
results
exhibit
that
irrespective
host
specification
COOH
offer
a
primary
site
through
hydrogen
bonding
interaction.
The
presence
more
relatively
stronger
secondary
edge
oxygen
ensure
GLU
moieties
are
superior
choice
over
ALU
efficient
binding.
energy
spectrum
exhibits
favorable
HOMO/LUMO
gap
variations
after
case
PDI
nature
residues.
by
combination
both
factors,
PDI-GLU
identified
most
suitable
molecule
among
derivatives.
Finally,
key
theoretical
predictions
later
experimentally
validated
analyzing
UV–visible
spectroscopy
NMR
studies,
wherein
mechanism
also
verified
EPR
FT-IR
studies.
ACS Applied Bio Materials,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 30, 2025
The
study
highlights
the
design,
synthesis,
and
photophysical
evaluation
of
two
pyrimidine-based
charge
transfer
probes
(compounds
1
2)
for
selective
detection
uric
acid
(UA)
in
aqueous
environments
biological
fluids.
Both
exhibited
distinct
spectral
responses
attributable
to
their
structural
differences,
with
compound
demonstrating
superior
sensitivity.
Quantitative
analysis
revealed
a
strong
linear
correlation
(R2
=
0.998)
between
UA
concentration
fluorescence
intensity,
enabling
as
low
0.12
μM,
which
is
well
within
clinically
relevant
range.
Mechanistic
investigations
confirmed
indispensable
role
pyrimidine
unit
forming
multipoint
hydrogen-bonding
interactions
UA,
induced
spectroscopic
changes
disrupted
probe
aggregates.
Environmental
factors
such
pH,
polarity,
temperature
were
systematically
examined,
revealing
that
performance
was
optimal
at
moderate
pH
(4-8)
60-70%
water
content,
elevated
temperatures
(50
°C)
enhancing
response
due
dissociation
supramolecular
Screening
diluted
human
urine
validated
practical
applicability
probe,
high
recovery
rates
minimal
matrix
interference.
also
utilized
HeLa
cells.
Also,
chemically
modified
paper
strips
developed
rapid,
on-site
UA.
The
naked-eye
detection
of
hazardous
pollutants
through
simple
and
cost-effective
techniques
with
greener
circular
economy
approach
is
great
interest
to
the
scientific
community
related
stakeholders
in
analytical
science.
