A highly topical set of perovskite oxides are high-sensitivity piezoelectric ones, among which Pb(Zr,Ti)O3 at the morphotropic phase boundary (MPB) between ferroelectric rhombohedral and tetragonal...

In this work, NaTaO₃ ceramics are prepared by conventional mixed oxide method and NaTaO₃ films are deposited by RF magnetron sputtering on Si/SiO₂/TiO₂/Pt substrates. The dielectric response of the obtained NaTaO₃ ceramics and films is analyzed as a function of frequency and temperature. Between 1 kHz and 1 MHz, the dielectric permittivity of NaTaO₃ ceramics is frequency independent and increases on cooling up to ∼324, which is the highest value ever reported for NaTaO₃ ceramics. In contrast, NaTaO₃ films exhibit a dielectric relaxation between ∼20 and 30 K, following the Arrhenius law with activation energy ∼51 meV and pre-exponential term ∼10⁻¹⁵ s and attributed to polaron hopping.

In this study, a molecularly imprinted polymer film (MIP) was prepared on the surface of a disposable carbon screen-printed electrode (C-SPE) using (3-acrylamidopropyl)trimethylammonium chloride (AMPTMA) as a functional monomer and the cancer biomarker carbohydrate antigen 15-3 (CA 15-3) as a template. The MIP was synthesized by in situ electropolymerization (ELP) of the AMPTMA monomer in the presence of the CA 15-3 protein on the C-SPE surface. The target was subsequently removed from the polymer matrix by the action of proteinase K, resulting in imprinted cavities with a high affinity for CA 15-3. Electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to characterize the different phases of the sensor assembly. Chemical and morphological analysis was performed using RAMAN and scanning electron microscopy (SEM). CA 15-3 was successfully detected in a wide working range from 0.001 U mL⁻¹ to 100 U mL⁻¹ with a correlation coefficient (R²) of 0.994 in 20 min. The MIP sensor showed minimal interference with other cancer proteins (CEA and CA 125). Overall, the developed device provides a rapid, sensitive, and cost-effective response in the detection of CA 15-3. Importantly, this comprehensive approach appears suitable for point-of-care (PoC) use, particularly in a clinical context.