The development of efficient antibiotic-releasing materials derived from sustainable and recyclable compounds represents a key area within biomedical materials science, particularly in the treatment of antibacterial infections. Herein, a Fe³⁺/terephthalate-based metal–organic framework (MIL-53) and a novel advanced material made of MIL-53 with biogenic hydroxyapatite (1) were prepared by solvothermal reactions, and these were studied in detail as a Penicillin-G-releasing material. After loading Penicillin G on 1 and MIL-53, the antibiotic percentage release was studied, and the antimicrobial effectiveness of each material was evaluated against two bacterial ATCC strains (E. coli and S. aureus) and various Penicillin-G-resistant uropathogenic strains such as E. coli isolates (HHM 25, ERV 6, and FGI 4). Functional, structural, and morphological characteristics of these materials were thoroughly studied by analytical tools (FTIR, XRD, BET, SEM-EDS, and XPS). The Penicillin G load did not exceed 50% in both materials. The Penicillin G adsorption mechanism involves several types of interactions with the materials. The release of the antibiotic was more efficient from MIL-53, where the load did not exceed 20%. The release was analyzed using mathematical models. They indicated that when Penicillin G is released from MIL-53, the process follows diffusion through a uniform matrix; however, 1 is more porous, which helps with the release by diffusion of Penicillin G, and 1 exhibits more than a 90% inhibition of the growth of bacteria and strains like MIL-53. This suggests a valuable approach to antibiotic activity against resistant pathogens. The use of composite materials derived from the Fe-MOF with a sustainable matrix of hydroxyapatite as antibiotic-releasing materials has been unexplored until now.

CuS nanoparticles (Np) were synthesized and deposited on synthetic sphalerite (S_P) using two different methods. Two nanoparticle products were obtained on the surface of S_P, Np1 and Np2, resulting in two active materials (Np1-S_P and Np2-S_P) with specific characteristics. Nanoparticles and active materials were characterized by TEM, XRD, SEM, and XPS. The collectors PAX and SIPX were adsorbed on Np1-S_P and Np2-S_P to determine the adsorption capacity. Method 1 provides a higher quantity of nanoparticles on S_P, which allows for the adsorption of a higher amount of SIPX. Method 1 was used to deposit nanoparticles on two natural sphalerites (S_N) with different iron contents. S_N, unlike S_P, can be used to test nanoparticle activation results in microflotation experiments. S_N was activated with nanoparticles (Np1-S_N) and using the traditional method (Cu-S_N). The recovery of 75% of zinc using the microflotation process suggests that the hydrophobicity of Np1-S_N is higher than that of Cu-S_N. Nanoparticles improve the hydrophobicity of S_N compared to the traditional activation used in the mining industry. These results suggest that using nanoparticles is an excellent option to activate minerals in flotation processes, decreasing the consumption of reagents and helping to mitigate negative impacts on the environment.

Semicrystalline polystyrene spheroidal nanoparticles (50–100 nm) were obtained via microemulsion polymerization. They were evaluated as coal collectors in a low-rank carbonaceous mineral containing 2% organic carbon. The recovery of coal using nanoparticles as collectors was 88.2%, in contrast to 53.2%, 46.4%, and 44.8% achieved using an amine-type compound, kerosene, and diesel, respectively. X-ray photoelectron spectroscopy (XPS) and zeta potential measurements confirmed the polystyrene–mineral surface chemical interaction. A Box–Behnken experimental design for flotation optimization was applied, and the results showed that the coal recovery increased up to 99.5% when the dosage of the collector was increased. A contact angle study and density functional theory calculations, together with XPS results, allowed us to postulate an interaction mechanism in which polystyrene nanoparticles adsorb onto the coal surface through hydrophobic interactions, rendering the oxidized surface hydrophobic and the coal buoyant by adhering to the gas bubbles.