This work brings the promise of MCM-41 mesoporous silica as a vehicle for red propolis for the development of controlled release drugs and delivery to a specific target site. The synthesis of MCM-41 by the sol–gel method with a pore size of approximately 3.6 nm and the incorporation of red propolis extract by the physical adsorption method in ethanolic medium were easily accomplished with around 15% encapsulation. MCM-41 and MCM-41 with red propolis (MCM-41/Pr) were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermal analysis, N2 adsorption–desorption, scanning electron microscopy, and an ultra-high-performance liquid chromatography–diode array detection (UPLC-DAD). In vitro release of encapsulated red propolis was analyzed in phosphate buffer at pH 7.2, 7.4, and 7.6. An in vitro test for MCM-41/Pr antioxidant activity was performed using 2,2-diphenyl-1-picrylhydrazyl as well as analysis of antibacterial activity against Staphylococcus aureus by the well diffusion method. UPLC-DAD analysis showed that the integrity of the red propolis constituents was maintained after the embed process, and the antioxidant and antibacterial activities were preserved.
28 February 2018 in Journal of Apicultural Research
The aim of the present study was to compare two nanoparticle composition loaded with Brazilian red propolis extract regarding its physicochemical characteristics and its antioxidant and antileishmanial activities. The red propolis nanoparticles in an aqueous medium and in solid-state presented particle size in a nanometric scale with an apparent size of 100–288 nm for the NEPE and 175–380 nm for the NPPE. ATR-FTIR and thermal analysis revealed an encapsulation of flavonoids from the red propolis extract in polymeric matrices for the multidrug delivery system. UPLC-DAD identified red propolis markers (flavonoids) in EPE, NEPE and NPPE. The efficiency of encapsulation (28.0–55.0% for NEPE and 61.2–81.0% for NPPE) were determined and calculated using UPLC-DAD. DPPH method showed the antioxidant activity of both EPE and nanoparticle compositions of red propolis. These polymeric matrices systems were able to encapsulate flavonoids from red propolis extract with specific characteristics of solubility and polarity. EPE and nanoparticles loaded with red propolis extract in the multi-constituent co-delivery system presented leishmanicidal activity and a good correlation was established between IC50 and efficiency of encapsulation. Red propolis nanoparticles exhibited leishmanicidal activity but NEPE presented a lower leishmanicidal effect in relation to NPPE, which showed similar activity compared to EPE. The nanopolymeric matrices choice should be established in propolis nanoparticle compositions to avoid lack of efficacy of bioproducts. Red propolis nanoparticles were shown to be a potential final bulk product for the preparation of various pharmaceutical and cosmetics compositions in therapy against diseases such as leishmaniasis. Scanning Electron Microscopy of red propolis nanoparticles (NEPE 30) (A). ATR-FTIR spectra of NPPE 30 and NPPE placebo (B). Chromatogram of the NPPE 30 (C). Determination of IC using leishmanicidal assay against Leishmania braziliensis for EPE, NEPE and NPPE (D).
Fluorescence of nanostructured hybrid material based on MCM-41 functionalized with chitosan and dansylglycine permits visualization of latent fingerprints.
The search for efficient oil spill remediation techniques leads to the use of physical, chemical, and biological methods, featuring both natural and modified lipophilic materials. Kapok fibers (Ceiba pentandra (L.) Gaerth) have been studied as a result of their unusual natural oil sorption capacity, which can be improved even further through physical or chemical treatments that augment their rugosity and alter their functional properties. Furthermore, the exact role of fiber morphology is not completely clear regarding the sorption process. Hence, this study investigated the efficacy of kapok fibers using different treatments, based on chemical and physical approaches, and characterized using advanced techniques (FTIR, SEM, AFM), aiming to improve the understanding of application possibilities in oil contamination scenarios. The results indicate that treatments using a low thermal intensity and low concentration do not lead to variation in sorption properties nor in surface structural features. Fiber rugosity varied from 4.40 to 12.35 nm, whereas an excessive increase in roughness was observed when the material was subject to more extreme conditions, such as a temperature of 120 °C and high concentrations (2.0 M) of both acid or alkali, accompanied by a loss in functionality and affecting the material sorption capacity. Thus, the study provides conditions to suggest that these treatments are not necessary for this type of material when inserted into sorption processes.