Lignin-based nano- and microcarriers are a promising biodegradable drug delivery platform inside of plants. Many wood-decaying fungi are capable of degrading the wood component lignin by segregated ...lignases. These fungi are responsible for severe financial damage in agriculture, and many of these plant diseases cannot be treated today. However, enzymatic degradation is also an attractive handle to achieve a controlled release of drugs from artificial lignin vehicles. Herein, chemically cross-linked lignin nanocarriers (NCs) were prepared by aza-Michael addition in miniemulsion, followed by solvent evaporation. The cross-linking of lignin was achieved with the bio-based amines (spermine and spermidine). Several fungicidesnamely, azoxystrobin, pyraclostrobin, tebuconazole, and boscalidwere encapsulated in situ during the miniemulsion polymerization, demonstrating the versatility of the method. Lignin NCs with diameters of 200–300 nm (determined by dynamic light scattering) were obtained, with high encapsulation efficiencies (70–99%, depending on the drug solubility). Lignin NCs successfully inhibited the growth of Phaeomoniella chlamydospora and Phaeoacremonium minimum, which are lignase-producing fungi associated with the worldwide occurring fungal grapevine trunk disease Esca. In planta studies proved their efficiency for at least 4 years after a single injection into Vitis vinifera (“Portugieser”) plants on a test vineyard in Germany. The lignin NCs are of high interest as biodegradable delivery vehicles to be applied by trunk injection against the devastating fungal disease Esca but might also be promising against other fungal plant diseases.
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IJS, KILJ, NUK, PNG, UL, UM
The amidation of fatty acid is an important reaction for synthesis of fatty alkolamines with a variety of pharmacological activities. The objective of this paper was to demonstrate the aminolysis ...direct and solvent of the triglycerides from the patawa oil by heterogeneous catalysis. The results of the amidation direct free solvents were favorable using 5% Al
2
O
3
as catalyst, with a conversion of 94% at 24 h of reaction. After spectroscopic characterization, we decided explore the antimicrobial tests of the fatty amides (FAA) against the
Staphylococcus aureus
strain (ATCC 33591), showing a MIC activity of 1.9612 mg/mL and the fatty ethyl esters (FAEE) a 3.4125 mg/mL MIC. Therefore, the synthesis direct free solvents of FAA by Al
2
O
3
from patawa oil was viable and innovative.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
With the objective to obtain immobilized Candida antarctica lipase B (CalB) with good activity and improved utilization rate, this study evaluated the influence of enzyme and crodamol concentrations ...and initiator type on the CalB enzyme immobilization in nanoparticles consisting of poly(methyl methacrylate) (PMMA) obtained by miniemulsion polymerization. The kinetic study of immobilized CalB enzyme in PMMA nanoparticles was evaluated in terms of monomer conversion, particle size, zeta potential, and relative activity. The optimum immobilization condition for CalB was compared with free enzyme in the p-NPL hydrolysis activity measurement. Results showed a higher CalB enzyme stability after 20 hydrolysis cycles compared with free CalB enzyme; in particular, the relative immobilized enzyme activity was maintained up to 40 %. In conclusion, PMMA nanoparticles proved to be a good support for the CalB enzyme immobilization and may be used as a feasible alternative catalyst in industrial processes.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Immobilization of cellulases on magnetic nanoparticles, especially magnetite nanoparticles, has been the main approach studied to make this enzyme, economically and industrially, more attractive. ...However, magnetite nanoparticles tend to agglomerate, are very reactive and easily oxidized in air, which has strong impact on their useful life. Thus, it is very important to provide proper surface coating to avoid the mentioned problems. This study aimed to investigate the immobilization of cellulase on magnetic nanoparticles encapsulated in polymeric nanospheres. The support was characterized in terms of morphology, average diameter, magnetic behavior and thermal decomposition analyses. The polymer nanospheres containing encapsulated magnetic nanoparticles showed superparamagnetic behavior and intensity average diameter about 150 nm. Immobilized cellulase exhibited broader temperature stability than in the free form and great reusability capacity, 69% of the initial enzyme activity was maintained after eight cycles of use. The magnetic support showed potential for cellulase immobilization and allowed fast and easy biocatalyst recovery through a single magnet.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Thiol‐ene polymerization has been pointed out as a promising technique to produce biobased polymers for biomedical applications due to its advantages, including mild conditions and rapid reaction ...rates without the formation of byproducts. Therefore, in this study different concentrations of magnetic nanoparticles (MNPs) were incorporated in poly(thioether‐ester) (PTEE) nanoparticles by thiol‐ene miniemulsion polymerization of biobased monomers to form both linear and branched cross‐linked polymers. Loading efficiencies up to approximately 95% (thermogravimetric analysis) of the MNPs within the polymer matrix were obtained. In addition, the substitution of the dithiol 1,4‐butanedithiol (64.2%) for the tetrathiol PTEMP (95.8%), increased the encapsulation efficiency by about 30%. Hybrid nanoparticles presented average mean diameters between 95 and260 nm with polydispersity index between 0.13 and 0.42 by DLS, negative zeta potentials around −45 mV and superparamagnetic behavior. The hyperthermia assays performed on breast cells (MDA‐MB 231) have shown that the cell death was dependent on the exposure time to the AC magnetic field and the reduction in cell viability was approximately 35%. These results demonstrated the production of superparamagnetic PTEE nanoparticles via thiol‐ene polymerization and highlight the promising application of these biobased materials for cancer treatment by hyperthermia.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Poly(urea-urethane) (PUU) nanoparticles with encapsulated superparamagnetic magnetite (Fe
3
O
4
) were obtained by interfacial miniemulsion polymerization and used as support for immobilization of ...lipase B from
Candida antarctica
(CALB). CALB enzyme was immobilized on magnetic PUU nanoparticles in two steps. The enzyme was immobilized in the lyophilized nanoparticles (magnetic PUU) after the support synthesis in phosphate buffer (pH 7.6) containing CALB, by the contact between nanoparticles and enzymatic solution. The mixture was incubated at 30 °C in an orbital shaker during 0.5 until 6 h to determine the time for maximum immobilization efficiency. The enzyme activity was determined by esterification reactions between lauric acid and propanol. Residual activities above 95 % in relation to free enzyme were obtained in 1 h of immobilization with enzyme concentration of 0.55 mg/mL. FTIR spectrum and SEM-FEG images were used to confirm the presence of CALB on magnetic support after immobilization and stability of support even after immobilization process, respectively. Thermal (40, 60, and 80 °C) and pH (pH 4, 7, and 10) stabilities, storage stability, and reuse were evaluated. CALB immobilized derivatives showed high stabilities with residual activities of 95, 100, and 100 % at 40, 60, and 80 °C, respectively, in 6 h of incubation. After incubation in different pH values, CALB immobilized derivative presented activities of 81, 76, and 69 % in relation to activities in the beginning of the stabilization process in pH 4, 7, and 10, respectively. Furthermore, CALB immobilized derivative reduces only 15 % of its activity after 30 days of storage at 4 °C. Reuse results showed that immobilized CALB on magnetic PUU nanoparticles led to 95 % of geranyl oleate conversion after 8 cycles of application demonstrating high stability of the CALB immobilized derivative under different conditions.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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•Thiol-ene polymers as promising biomedical materials.•Applications in tissue engineering, drug delivery or dental restoration.•Hydrogels, resins and nanoparticles by thiol-ene ...polymerisation.•Biodegradable and potentially biocompatible thiol-ene polymers.
Thiol-ene reactions have been utilised for surface functionalization, molecules conjugation, crosslinking, grafting, and polymerisation of renewable monomers. The applications described in the literature comprise utilisation as protective polymers, photo-curable materials, highly uniform glasses, elastomers, adhesive and even dental restorative resins. Even though novel materials are arising from thiol-ene chemistry, little attention has been paid to the potential biomedical applications, which these materials possess. Some applications have been researched for thiol-ene polymers in the past few years within the biomedical field, mostly as hydrogels. These polymers have been successfully synthesized comprising different kinds of multifunctional enes and thiols. Functional groups of interest are those which yield polymers that present hydrolysable bonds in the polymeric chain such as ester group. However, there is a lack of information available in the literature regarding biocompatibility and biodegradability of thiol-ene polymers, and their utilisation in tissue engineering, drug delivery or dental restoration. Thiol-ene polymers as biomedical materials is a field still underexplored, not many papers have been published under this subject even though there are many advantages in using these materials.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Biodegradability is a key feature for the application of polymeric devices in medicine. This study reports an experimental and theoretical study of the degradation of poly(thioether-ester) (PTEe) ...nanoparticles in aqueous media. The α,ω-diene diester derived from vegetable oil, 1,3-propylene diundeca-10-polenoate (Pd10e), was used as monomer in the solvent-free synthesis of Pd10e-based nanoparticles (A-PTEe nanoparticles) via thiol-ene miniemulsion polymerization. The theoretical partition coefficients of A-PTEe and a PTEe based on dianhydro-
d
-glucityl diundec-10-enoate (DGU) (B-PTEe nanoparticles) were calculated using density functional theory (DFT), in order to compare their degradation behavior. The results showed that A-PTEe is more hydrophilic than B-PTEe, thus indicating the possible faster degradation of the former. The experimental degradation studies showed that, in fact, A-PTEe nanoparticles are faster degraded than B-PTEe, presenting substantial molecular weight decrease, which confirms the theoretical results. The effects of degradation could be observed in the chemical composition and thermal properties of the polymer. Considering its applicability potential as a biomaterial due to its fast degradation behavior, the cytotoxicity of A-PTEe nanoparticles and its degradation products were evaluated. In vitro assays confirmed the biocompatibility of A-PTEe nanoparticles and its degradation products when exposed on fibroblasts and red blood cells. These results suggest A-PTEe nanoparticles can be promising candidates as biobased nanocarriers for biomedical applications.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Understanding the complex behavior and dynamics of cellular membranes is integral to gain insight into cellular division and fusion processes. Bottom‐up synthetic cells are as a platform for ...replicating and probing cellular behavior. Giant polymer vesicles are more robust than liposomal counterparts, as well as having a broad range of chemical functionalities. However, the stability of the membrane can prohibit dynamic processes such as membrane phase separation and division. Here, we present a method for manipulating the membrane of giant polymersomes using a temperature responsive polymer. Upon elevation of temperature deformation and phase separation of the membrane was observed. Upon cooling, the membrane relaxed and became homogeneous again, with infrequent division of the synthetic cells.
Membrane manipulation of giant polymers using a temperature‐responsive polymer is reported. The strategy makes it possible to develop materials and create compartmentalized systems that can mimic the adaptive properties of biomembranes.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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•DETC loaded in beeswax-copaiba oil nanoparticles (SLNs).•SLNs did not present any cytotoxic effect on peritoneal macrophages.•SLNs showed an excellent leishmanicidal activity against ...L. amazonesis promastigotes.•SLNs presented a two times higher selectivity index than free DETC.
Leishmaniasis is considered a neglected tropical disease that represents a Public Health problem due to its high incidence. In the search of new alternatives for Leishmaniasis treatment diethyldithiocarbamate (DETC) has shown an excellent leishmanicidal activity and the incorporation into drug carrier systems, such as solid lipid nanoparticles (SLNs), is very promising. In the present work DETC loaded in beeswax nanoparticles containing copaiba oil were obtained by the double emulsion/melt technique. The nanoparticles were characterized and leishmanicidal activity against L. amazonensis promastigotes forms and cytotoxicity in murine macrophages were evaluated. SLNs presented size below 200 nm, spherical morphology, negative charge surface, high encapsulation efficiency, above 80%, and excellent stability. Moreover, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses were performed to evaluate the chemical structure and possible interactions between DETC and SLNs. SLNs provided a protection for DETC, decreasing its cytotoxic effects in macrophages, which led to an improvement in the selectivity against the parasites, which almost doubled from free DETC (11.4) to DETC incorporated in SLNs (18.2). These results demonstrated that SLNs had a direct effect on L. amazonensis promastigotes without affect the viability of macrophage cell, can be a promising alternative therapy for the cutaneous treatment of L. amazonensis
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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