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Background The increasing rate of cancer cases is alarming. In 2018, 9.6 million people died of the disease (WHO 2020). Current treatments, such as chemical therapy using cisplatin (CisPt) as a basis, cause considerable collateral damage to the patient (Ahmad 2017). CisPt acts as an alkylating agent with affinity to DNA, binds to the guanine and cytosine residues, and prevents the processes of replication and transcription of the genetic material, resulting in cell death by apoptosis (Ahmad 2017). However, cisplatin is unable to differentiate between normal and cancerous cells. Moreover, cancer cells can develop

In the search of lead-free piezoelectric materials, ceramic processing techniques offer potential tools to increase the piezoelectric and ferroelectric properties in addition to new chemical compositions. Powders of pure BNKT16 (Bi 0.5 (Na 0.84 K 0.16 ) 0.5 TiO 3 ) phase were synthesized by sol-gel method with a low crystallization temperature (750 ℃ ). Ceramic samples were sintered by pressureless sintering (PLS), sinter-forging (SF), and spark plasma sintering (SPS) techniques. Structural, morphological, and chemical characterizations were performed by XRD, Raman, EDS, and SEM. Sintered samples by PLS and SF exhibit rod-like grains associated to bismuth volatility. The highest remanent polarization (11.05 µC/cm 2 ), coercive field (26.2 kV/mm), and piezoelectric coefficient (165 pC/N) were obtained for SF sample. The piezoresponse force microscopy (PFM) analysis shows that the crystallites at the nanoscale exhibit piezoelectric phenomenon and the highest piezoelectric response is reported for PLS sample. The presence of the rhombohedral phase, the increase in grain and crystallite size, and the oriented rod-like inclusions favoring the crystallographic texture are facts that enhance the piezoelectric coefficient for BNKT16 piezoceramics.

In this study, films of O-carboxymethyl chitosan with Mimosa tenuiflora extract were manufactured, characterized, and evaluated. In this work, both the synthesis of O-carboxymethyl chitosan and the extraction of the active ingredient of Mimosa tenuiflora extract from the cortex are described. First, the extract of Mimosa tenuiflora in water was obtained by precipitation with ethanol, filtering, and concentrating. Subsequently, a study was conducted of scratch wound healing to determine the optimal concentration of extract to be used in the manufacture of films. The produced O-carboxymethyl chitosan films and the Mimosa tenuiflora extract were mixed, and their chemical composition, tensile properties, and wettability were characterized by Fourier-transform infrared spectroscopy, mechanical tests, and contact angle measurement. The antimicrobial properties of the films were tested by turbidimetry using two types of bacteria. In addition, a study of the enzymatic degradation of the films with the enzyme lysozyme was performed. Finally, in vitro studies to assess the biocompatibility and cytotoxicity of films with fibroblastic cells were carried out as well as the kinetic analysis of healing in mice. It was found that the addition of Mimosa tenuiflora extract in the polymer matrix of the films made with O-carboxymethyl chitosan improves the proliferation of fibroblast and accelerates wound healing, thus providing a novel biomaterial for skin regeneration.

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