Showing papers by "Shouzhuo Yao published in 2001"
TL;DR: A new bio-mimetic quartz crystal thickness-shear-mode (TSM) sensor, using an imprinted polymer coating as the sensitive material, has been fabricated and applied to the determination of nicotine (NIC) in human serum and urine.
60 citations
TL;DR: A new bio-mimetic bulk acoustic wave (BAW) sensor for paracetamol, with a high selectivity and sensitivity, was fabricated by using the molecularly imprinted polymer (MIP) as the sensing material, and exhibited good reproducibility.
56 citations
TL;DR: In this article, a new biomimic bulk acoustic wave (BAW) sensor with a molecularly imprinted polymer (MIP) coating has been designed and applied to the determination of phenacetin in human serum and urine.
Abstract: A new biomimic bulk acoustic wave (BAW) sensor with a molecularly imprinted polymer (MIP) coating has been designed and applied to the determination of phenacetin in human serum and urine. The MIP was prepared using phenacetin as the imprinted molecule and methacrylic acid as the functional monomer. The sensor showed high selectivity and sensitivity in aqueous system. A linear calibration response curve between 5.0×10 −8 M and 5.0×10 −4 M was obtained and the detection limit was 5.0×10 −9 M. The coating of the sensor was stable and can be reused for many times. In the determination of real samples, satisfactory results were achieved.
39 citations
TL;DR: The preparation and characterization of electrosynthesized poly(o-phenylenediamine) (iPoPD) as a molecular imprinting material were studied by an in situ quartz crystal impedance method and it offers possibilities for sensor miniaturization.
Abstract: The preparation and characterization of electrosynthesized
poly(o-phenylenediamine) (iPoPD) as a molecular imprinting
material were studied by an in situ quartz crystal impedance
method. The changes of Δf0,
ΔR1, ΔL1 and
ΔC0 suggest that the polymer film was compact and
rigid. The thickness shear mode (TSM) acoustic sensor modified with this
material exhibits molecular recognition ability to the template molecule of
DL-phenylalanine. In the range 2–20 mM, a linear
relationship between the frequency shift Δf0 and
logC was found from the calibration graph. Scatchard analysis of
the relevant calibration graph offers information on the equilibrium of the
binding interaction and the recognition sites. Using this
electropolymerization technology, the preparation of the sensor was very
simple and the reproducibility of preparation was very good. In particular,
it offers possibilities for sensor miniaturization.
38 citations
TL;DR: A molecularly imprinted polymer for aminopyrine was synthesized using methacrylic acid as functional monomer and employed as the recognition element of a piezoelectric bulk acoustic wave biomimetic sensor for am inopyrines, which exhibited high selectivity and sensitivity to aminipyrine.
Abstract: A molecularly imprinted polymer for aminopyrine was
synthesized using methacrylic acid as functional monomer. The polymer was
employed as the recognition element of a piezoelectric bulk acoustic wave
biomimetic sensor for aminopyrine. Influencing factors were investigated in
detail and optimized. This sensor exhibited high selectivity and
sensitivity to aminopyrine. The response range of the sensor was between
5.0 × 10−8 and 1.0 × 10−4 M
with a detection limit of 2.5 × 10−8 M in the
aqueous system. Scatchard analysis with UV spectrophotometry showed that
the same class of binding sites was formed in the molecularly imprinted
polymer in the studied concentration range, and the dissociation constant
and the apparent maximum number of these binding sites were estimated to be
2.29 mM and 165.0 μmol g−1 dry polymer, respectively.
Impedance analysis was employed to verify the imprinting effect and lack of
variation in the viscoelasticity of the polymer coating during
detection.
27 citations
TL;DR: In this paper, simultaneous determination of Ca (2+) and Mg(2+) cations in saliva, urine was achieved using an ion chromatography method, in which a piezoelectric quartz crystal (PQC) sensor was used as a detector, and a solution containing tartaric acid (4 mmol 1(-1)) and ethylenediamine (2 mmol 1-1)) as a mobile phase.
17 citations
TL;DR: The construction of an anion-selective bulk acoustic wave (BAW) sensor for the direct determination of phenytoin sodium for the first time was found to be sensitive, rapid and easy to handle without pretreatment of the sample.
Abstract: This paper describes the construction of an anion-selective bulk acoustic wave (BAW) sensor for the direct determination of phenytoin sodium for the first time. Based on the sensitive mass response of a piezoelectric quartz crystal (PQC) and selective adsorption–desorption across the modified film, the BAW sensor was fabricated by coating a polyvinylchloride (PVC) film containing activator on one side of a PQC. The method was found to be sensitive, rapid and easy to handle without pretreatment of the sample. The logarithm of the frequency shift of the PQC shows a linear relationship to the logarithm of the concentration of phenytoin over the range 6.7 × 10−8–8.0 × 10−4 M with a detection limit of 1.0 × 10−8 M at pH 10.0. Recoveries were in the range 98.5–102.0%. Influencing factors were examined and optimized. Also discussed is the preliminary application of the phenytoin BAW sensor in serum
and injection. The results for real samples obtained by the proposed method agreed with those obtained by conventional methods.
16 citations
TL;DR: In this paper, a non-suppressed ion chromatography (IC) method with a bulk acoustic wave sensor (BAW) as detector, and 1.5 mmol/L potassium hydrogenphthalate (KHP) as mobile phase was used.
Abstract: In the present paper, nitrate and nitrite in foodstuffs and saliva were simultaneously determined using a non-suppressed ion chromatography (IC) method with a bulk acoustic wave sensor (BAW) as detector, and 1.5 mmol/L potassium hydrogenphthalate (KHP) as mobile phase. The IC-BAW method is simple, rapid and accurate. The determination limits for nitrite and nitrate are 0.20 and 0.30 mg/L, respectively. The IC-BAW is comparable and agrees with the conventional spectrophotometric method for nitrite and nitrate determination.
15 citations
TL;DR: In this article, a non-linear least square regression analysis of synchronously acquired conductance and susceptance data is performed to measure the electrical equivalent circuit parameters and frequency shifts of a piezoelectric PQC resonator.
12 citations
TL;DR: The results showed that the proposed method has potential applications in interfacial studies of biomaterials, since these combined techniques have advantages in real time providing multidimensional piezoelectric and electrochemical impedance information.
12 citations
TL;DR: The motional resistance shift curves indicate that the viscosity of the test solutions decreases during the hydrolysis process, and the variations of equivalent circuit parameters of piezoelectric quartz crystal (PQC) during the enzymatic degradation are discussed.
TL;DR: An ion-selective piezoelectric (ISP) sensor was successfully applied for the determination of niacinamide in serum and urine and the results for real samples obtained were in good agreement with those obtained by the conventional methods.
TL;DR: In this paper, the resonance behavior and the electric equivalent circuit of the ringed-electrode piezoelectric sensor (REPS) operating in liquid phase have been studied.
TL;DR: In this paper, a series of piezoelectric quartz crystal sensors were employed to monitor the sedimentation of erythrocytes outside or under a magnetic field, and the effect of magnetic fields on the sedimentations of the erythropoietin containing deoxyhemoglobin or methemoglobin was measured by the relative differential of frequency shifts.
TL;DR: The variations of equivalent circuit parameters of the piezoelectric quartz crystal (PQC) during the enzymatic degradation are discussed and the initial hydrolysis rate of CS by HAse is obtained from the changes in viscosity and density with incubation time.