Docetaxel (DTX) is a non-selective antineoplastic agent with low solubility and a series of side effects. The technology of pH-sensitive and anti-epidermal growth factor receptor (anti-EGFR) immunoliposomes aims to increase the selective delivery of the drug in the acidic tumor environment to cells with EFGR overexpression. Thus, the study aimed to develop pH-sensitive liposomes based on DOPE (dioleoylphosphatidylethanolamine) and CHEMS (cholesteryl hemisuccinate), using a Box–Behnken factorial design. Furthermore, we aimed to conjugate the monoclonal antibody cetuximab onto liposomal surface, as well as to thoroughly characterize the nanosystems and evaluate them on prostate cancer cells. The liposomes prepared by hydration of the lipid film and optimized by the Box–Behnken factorial design showed a particle size of 107.2 ± 2.9 nm, a PDI of 0.213 ± 0.005, zeta potential of −21.9 ± 1.8 mV and an encapsulation efficiency of 88.65 ± 20.3%. Together, FTIR, DSC and DRX characterization demonstrated that the drug was properly encapsulated, with reduced drug crystallinity. Drug release was higher in acidic pH. The liposome conjugation with the anti-EGFR antibody cetuximab preserved the physicochemical characteristics and was successful. The liposome containing DTX reached an IC₅₀ at a concentration of 65.74 nM in the PC3 cell line and 28.28 nM in the DU145 cell line. Immunoliposome, in turn, for PC3 cells reached an IC₅₀ of 152.1 nM, and for the DU145 cell line, 12.60 nM, a considerable enhancement of cytotoxicity for the EGFR-positive cell line. Finally, the immunoliposome internalization was faster and greater than that of liposome in the DU145 cell line, with a higher EGFR overexpression. Thus, based on these results, it was possible to obtain a formulation with adequate characteristics of nanometric size, a high encapsulation of DTX and liposomes and particularly immunoliposomes containing DTX, which caused, as expected, a reduction in the viability of prostate cells, with high cellular internalization in EGFR overexpressing cells.

Tree-exuded gums are natural polymers that represent an abundant raw material in the food and pharmaceutical industries. The cashew gum can be obtained by exudation of trees of the genus Anacardium, a native species of the Brazilian northeast; its polymer consists of monosaccharide units propitious to the action of chemical reactions that tend to improve their intrinsic characteristics among them, as the degree of hydro-solubility. The objective of this work was to modify the exudate gum of Anacardium occidentale (cashew gum (CG)) through an amine reaction. The modification was confirmed by Nuclear Magnetic Resonance (¹H NMR), infrared spectroscopy (FTIR), gel permeation chromatography (GPC), zeta potential, and thermogravimetric analysis (TG). In addition, the chemical modification altered the molar mass and surface charge of the CG, and the amino group binding to the CG polymers was confirmed by FTIR spectra. In addition, cytotoxicity tests were performed where cell viability was estimated by an MTT assay on RAW 264.7 macrophages. Through these tests, it was found that the amine caused an increase in the thermal stability of the amino compounds and did not present cytotoxic potential at concentrations below 50.0 mg/L.

This work is based on research aiming to extract and identify flavonoids from jaborandi (Pilocarpus microphyllus) leaves and investigate their antioxidant and acute antinociceptive capacity. Characterization of the constituents of the ethyl acetate fraction (EtOAcF) obtained from the methanolic extract (ME) was performed by UV-Vis spectrophotometry, infrared spectroscopy, high-performance liquid chromatography (HPLC), mass spectrometry (MS), and cyclic voltammetry, demonstrating the possible majority component of this fraction, the flavone chrysin. Its solubility properties in HPLC are very close to those of the flavonol quercetin, revealing the characteristic presence of this group. An MS spectrum of the fraction revealed a major protonated molecule of m/z 254.9 [M+H]⁺. The EtOAcF fraction showed three oxidation processes at 0.32 V, 0.54 V, and 0.73 V vs. Ag/AgCl. Three reduction processes at the respective potentials: 0.60 V, −0.03 V, and -0.24 V vs. Ag/AgCl, indicating potential antioxidant activity. At DPPH and ABTS antioxidant radical capture assay, The IC₅₀ obtained was 0.5 mg/mL and 0.81 mg/mL, respectively. In vivo test to determine the mechanical nociceptive threshold in the von Frey test, the dose of 100 mg/kg of the EtOAcF was able to cause inhibition of behavioral changes in neuropathy. The results obtained in this study demonstrate the biological potential of an EtOAcF derived from jaborandi leaves.

Quinones are a classic example of molecules isolated from natural products. These compounds are secondary metabolites produced by plants, fungi, bacteria, and insects and correspond to an interesting chemical class ubiquitously found in nature. The [rel-8α-Hydroxy-5-hydroxymethyl-2-methoxy-8α, β-methyl-7, 8, 8a, 9-tetahydro-1, 4-anthracenedione] [oncocalyxone A, onco-A] is a benzoquinone of dark red color isolated from the ethanolic extract of the species Cordia oncocalyx (Auxemma oncocalyx Allem). In this review, we aimed to investigate the main biological activities described for oncocalyxone A, as well as its isolation and characterization processes. For this review, the following descriptors were employed in multiple databases: medicinal plants, quinones, Auxemma oncocalyx, Cordia oncocalyx, biological activity. Besides, experimental papers published in international journals and with full text available were used as inclusion criteria. The biological activity profiles found for onco-A according to the literature were: antiproliferative/cytotoxic effects against SW1573 (alveolar cell carcinoma) and CCD922 (normal skin fibroblasts) cell lines; anti-inflammatory and analgesic potential; inhibitory effect on cell growth and DNA reactivity; antiplatelet activity; antitumor potential; anti-glycation agent; beneficial and/or toxic potential in goats and neuroinhibitory effect; antibacterial and antibiofilm activity. The substance has a broad spectrum of pharmacological applications, most of which are associated with its cytotoxic activity. The work also intends to compile the activities described in the literature, to understand how the molecule acts on the various targets, but, in some cases, more in-depth research is needed to elucidate the mechanisms of action.

Poly(methyl methacrylate) (PMMA) is a polymer that can be used in applications requiring its exposition to gamma radiation, nevertheless, the radiation induces main chain scission backbone, leading to modification in some properties. Therefore, using materials such as layered double hydroxide (LDH), was evaluated as a new radiation shielding agent. This work synthesized LDH and added to PMMA by an in-situ polymerization method. Viscosimetric analysis showed that LDH at 0.25 wt% concentration promotes polymer radiolytic protection of 90% against damage caused by gamma radiation. The topographic images obtained by AFM revealed increasing PMMA/LDH film roughness, which impacted the lower film transmittance. The combined effect of LDH and gamma radiation interferes with the degradation process of PMMA, promoting reduced rigidity, greater mobility of polymer chains, and lower optical gap energy. Thus, these results open a promising path for using LDH as additives in polymers exposed to gamma radiation.