The development of materials based on thermoplastic starch (TPS) is an excellent alternative to replace or reduce the use of petroleum-derived polymers. The abundance, renewable origin, biodegradability, biocompatibility, and low cost of starch are among the advantages related to the application of TPS compared to other thermoplastic biopolymers. However, through the literature review, it was possible to observe the need to improve some properties, to allow TPS to replace commonly used polyolefins. The studies reviewed achieved these modifications were achieved by using plasticizers, adjusting processing conditions, and incorporating fillers. In this sense, the addition of nanofillers proved to be the main modification strategy due to the large number of available nanofillers and the low charge concentration required for such improvement. The improvement can be seen in thermal, mechanical, electrical, optical, magnetic, antimicrobial, barrier, biocompatibility, cytotoxicity, solubility, and swelling properties. These modification strategies, the reviewed studies described the development of a wide range of materials. These are products with great potential for targeting different applications. Thus, this review addresses a wide range of essential aspects in developing of this type of nanocomposite. Covering from starch sources, processing routes, characterization methods, the properties of the obtained nanocomposites, to the various applications. Therefore, this review will provide an overview for everyone interested in working with TPS nanocomposites. Through a comprehensive review of the subject, which in most studies is done in a way directed to a specific area of study. Graphical Abstract

A flexible sensor based on polymer poly (butylene adipate-co-terephthalate) (PBAT) mixed with graphite was surface modified with AuNP (gold nanoparticule) and copper phthalocyanine using Layer-by-Layer (LbL) technique for simultaneous determination of catechol (CC) and paraquat (PQ). The device with and without modification was characterized by contact angle, Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR). Electrochemical characterization was performed by Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). Differential Pulse Voltammetry (DPV) technique was used to detect CC and PQ molecules in an interval of 100 to 200 μ M, some parameters were obtained from the analytical curve, such as linear regression values (R ² ) equal to 0.9998 and 0.9993 and detection limit (LOD) equal to 1.36 × 10 ⁻⁶ and 1.31 × 10 ⁻⁶ for CC and PQ, respectively. The sensor (g-PBAT/AuNP-PAH/CuTsPc) ₃ presented good stability, reproducibility, and repeatability, with recovery values ranging between 98.4%–105.6% for CC and 94.4%–106.1% for PQ when the sensor was subjected to analysis of samples contaminated with tap water. Electrodes produced in this work had the advantage of being flexible, disposable, reproducible, and of low manufacturing cost, which makes them attractive for portable environmental analysis.

This research aims to study flexible sensors based on a poly(butylene adipate-co-terephthalate) (PBAT) biodegradable polymer and graphite. Sensors were modified through the layer-by-layer (LbL) technique to improve their electrochemical behavior for paraquat (PQ) detection. Nanostructured films were obtained by alternating layers of anionic and cationic materials, carbon nanotubes (CNTs), and polypyrrole (PPY), respectively. The devices, with and without modification, were characterized by contact angle, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). Electrochemical characterization was labeled via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). PQ molecules were detected using the differential pulse voltammetry (DPV) technique in a concentration range of 0.1 to 2.1 µM. The sensor detection limit (LOD) was obtained using the analytical curve, with it being equal to 0.073 µM. The LbL film gPBAT(PPY/CNT)_n sensor showed good stability, reproducibility, and repeatability, with recovery values ranging from 99.4% to 109.3% for PQ when the analyzed samples were contaminated with tap water. The produced electrodes have the advantage of being flexible, disposable, reproducible, and of low manufacturing cost, which makes them attractive for portable environmental analysis.