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1.
Adv Mater ; 36(3): e2307747, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37990971

RESUMO

Current treatments for modulating the glial-mediated inflammatory response after spinal cord injury (SCI) have limited ability to improve recovery. This is quite likely due to the lack of a selective therapeutic approach acting on microgliosis and astrocytosis, the glia components most involved after trauma, while maximizing efficacy and minimizing side effects. A new nanogel that can selectively release active compounds in microglial cells and astrocytes is developed and characterized. The degree of selectivity and subcellular distribution of the nanogel is evaluated by applying an innovative super-resolution microscopy technique, expansion microscopy. Two different administration schemes are then tested in a SCI mouse model: in an early phase, the nanogel loaded with Rolipram, an anti-inflammatory drug, achieves significant improvement in the animal's motor performance due to the increased recruitment of microglia and macrophages that are able to localize the lesion. Treatment in the late phase, however, gives opposite results, with worse motor recovery because of the widespread degeneration. These findings demonstrate that the nanovector can be selective and functional in the treatment of the glial component in different phases of SCI. They also open a new therapeutic scenario for tackling glia-mediated inflammation after neurodegenerative events in the central nervous system.


Assuntos
Polietilenoglicóis , Polietilenoimina , Traumatismos da Medula Espinal , Camundongos , Animais , Nanogéis/uso terapêutico , Traumatismos da Medula Espinal/patologia , Neuroglia/patologia , Microglia
2.
J Biotechnol ; 377: 23-33, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37879569

RESUMO

Polyhydroxyalkanoates (PHA) are among the most promising bio-based alternatives to conventional petroleum-based plastics. These biodegradable polyesters can in fact be produced by fermentation from bacteria like Cupriavidus necator, thus reducing the environmental footprint of the manufacturing process. However, ensuring consistent product quality attributes is a major challenge of biomanufacturing. To address this issue, the implementation of real-time monitoring tools is essential to increase process understanding, enable a prompt response to possible process deviations and realize on-line process optimization. In this work, a soft sensor based on in situ Raman spectroscopy was developed and applied to the in-line monitoring of PHA biomanufacturing. This strategy allows the collection of quantitative information directly from the culture broth, without the need for sampling, and at high frequency. In fact, through an optimized multivariate data analysis pipeline, this soft sensor allows monitoring cell dry weight, as well as carbon and nitrogen source concentrations with root mean squared errors (RMSE) equal to 3.71, 7 and 0.03 g/L, respectively. In addition, this tool allows the in-line monitoring of intracellular PHA accumulation, with an RMSE of 14 gPHA/gCells. For the first time, also the number and weight average molecular weights of the polymer produced could be monitored, with RMSE of 8.7E4 and 11.6E4 g/mol, respectively. Overall, this work demonstrates the potential of Raman spectroscopy in the in-line monitoring of biotechnology processes, leading to the simultaneous measurement of several process variables in real time without the need of sampling and labor-intensive sample preparations.


Assuntos
Cupriavidus necator , Poli-Hidroxialcanoatos , Poli-Hidroxialcanoatos/metabolismo , Análise Espectral Raman , Poliésteres/metabolismo , Fermentação , Biotecnologia , Cupriavidus necator/metabolismo
3.
Langmuir ; 39(29): 10133-10144, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37435842

RESUMO

After having demonstrated their potential in biomedical applications, thermo-responsive block copolymers that are able to self-assemble into nano-objects in response to temperature modifications are becoming more and more appealing in other sectors, such as the oil and gas and lubricant fields. Reversible addition-fragmentation chain transfer (RAFT) polymerization-induced self-assembly has been demonstrated as a valuable strategy for producing nano-objects from modular block copolymers in non-polar media, required for the mentioned applications. Although the influence of the nature and size of the thermo-responsive block of these copolymers on the properties of the nano-objects is extensively studied in the literature, the role of the solvophilic block is often neglected. In this work, we elucidate the role of the main microstructural parameters, including those of the solvophilic portion, of block copolymers produced by RAFT polymerization in the hydrocarbon blend decane/toluene 50:50 v/v on the thermo-responsive behavior and colloidal properties of the resulting nano-objects. Two long-aliphatic chain monomers were employed for the synthesis of four macromolecular chain transfer agents (macroCTAs), with increasing solvophilicity according to the number of units (n) or length of the alkyl side chain (q). Subsequently, the macroCTAs were chain-extended with different repeating units of di(ethylene glycol) methyl ether methacrylate (p), leading to copolymers that are able to self-assemble below a critical temperature. We show that this cloud point can be tuned by acting on n, p, and q. On the other hand, the colloidal stability, expressed in terms of area of the particle covered by each solvophilic segment, is only a function of n and q, which provides a way for controlling the size distribution of the nano-objects and to decouple it from the cloud point.

4.
Bioconjug Chem ; 34(6): 1084-1095, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37221455

RESUMO

Polyamidoamine (PAMAM) dendrimers are among the most studied cationic polymers as non-viral gene delivery vectors. However, an "ideal" PAMAM-based gene delivery vector is still missing due to the high manufacturing costs and non-negligible cytotoxicity associated with the use of high-generation dendrimers, whereas low-generation dendrimers are far from displaying efficient gene transfection. In order to cover this gap in the literature, in this study, we propose the functionalization of the outer primary amines of PAMAM G2 and PAMAM G4 with building blocks bearing fluorinated moieties along with a guanidino functional group. We have designed and synthetized two fluorinated arginine (Arg)-based Michael acceptors which were straightforwardly "clicked" to PAMAM dendrimers without the need for coupling reagents and/or catalysts. The obtained conjugates, in particular, derivative 1 formed starting from the low-cost PAMAM G2 and a building block bearing two trifluoromethyl groups, were able to efficiently complex plasmid DNA, had negligible cytotoxicity, and showed improved gene transfection efficiency as compared to undecorated PAMAM dendrimers and a corresponding unfluorinated PAMAM-Arg derivative, with derivative 1 being two orders of magnitude more efficient than the gold standard branched polyethylenimine, bPEI, 25 kDa. These results highlight the importance of the presence of trifluoromethyl moieties for both gene transfection and a possible future application in 19F magnetic resonance imaging.


Assuntos
Dendrímeros , Transfecção , Técnicas de Transferência de Genes , Terapia Genética
5.
J Chromatogr A ; 1692: 463868, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36803771

RESUMO

Protein PEGylation, i.e. functionalization with poly(ethylene glycol) chains, has been demonstrated an efficient way to improve the therapeutic index of these biopharmaceuticals. We demonstrated that Multicolumn Countercurrent Solvent Gradient Purification (MCSGP) is an efficient process for the separation of PEGylated proteins (Kim et al., Ind. and Eng. Chem. Res. 2021, 60, 29, 10764-10776), thanks to the internal recycling of product-containing side fractions. This recycling phase plays a critical role in the economy of MCSGP as it avoids wasting valuable product, but at the same time impacts its productivity extending the overall process duration. In this study, our aim is to elucidate the role of the gradient slope within this recycling stage on the yield and productivity of MCSGP for two case-studies: PEGylated lysozyme and an industrially relevant PEGylated protein. While all the examples of MCSGP in the literature refer to a single gradient slope in the elution phase, for the first time we systematically investigate three different gradient configurations: i) a single gradient slope throughout the entire elution, ii) recycling with an increased gradient slope, to shed light on the competition between volume of the recycled fraction and required inline dilution and iii) an isocratic elution during the recycling phase. The dual gradient elution proved to be a valuable solution for boosting the recovery of high-value products, with the potential for alleviating the pressure on the upstream processing.


Assuntos
Anticorpos Monoclonais , Distribuição Contracorrente , Solventes , Polietilenoglicóis
6.
J Chromatogr A ; 1681: 463487, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36115185

RESUMO

Conjugation of biopharmaceuticals to polyethylene glycol chains, known as PEGylation, is nowadays an efficient and widely exploited strategy to improve critical properties of the active molecule, including stability, biodistribution profile, and reduced clearance. A crucial step in the manufacturing of PEGylated drugs is the purification. The reference process in industrial settings is single-column chromatography, which can meet the stringent purity requisites only at the expenses of poor product recoveries. A valuable solution to this trade-off is the Multicolumn Countercurrent Solvent Gradient Purification (MCSGP), which allows the internal and automated recycling of product-containing side fractions that are typically discarded in the batch processes. In this study, an ad hoc design procedure was applied to the single-column batch purification of an industrially relevant PEGylated protein, with the aim of defining optimal collection window, elution duration and elution buffer ionic strength to be then transferred to the MCSGP. This significantly alleviates the design of the continuous operation, subjected to manifold process parameters. The MCSGP designed by directly transferring the optimal parameters allowed to improve the yield and productivity by 8.2% and 17.8%, respectively, when compared to the corresponding optimized batch process, ensuring a purity specification of 98.0%. Once the efficacy of MCSGP was demonstrated, a detailed analysis of its cost of goods was performed and compared to the case of single-column purification. To the best of our knowledge, this is the first example of a detailed economic investigation of the MCSGP across different manufacturing scenarios and process cadences of industrial relevance, which demonstrated not only the viability of this continuous technology but also its flexibility.


Assuntos
Produtos Biológicos , Distribuição Contracorrente , Distribuição Contracorrente/métodos , Polietilenoglicóis , Solventes/química , Distribuição Tecidual
7.
Biotechnol Bioeng ; 119(7): 1861-1872, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35338661

RESUMO

Oligonucleotides (ONs) are breaking through in the biopharmaceutical industry as a promising class of biotherapeutics. The main success of these molecules is due to their peculiar way of acting in the cellular process, regulating the gene expression and hence influencing the protein synthesis at a pretranslational level. Although the Food and Drug Administration (FDA) already approved a few ON-based therapeutics, their production cost strongly limits large-scale manufacturing: a situation that can be alleviated through process intensification. In this study, we address this problem by developing an efficient and continuous chromatographic purification process for ONs. In particular, we considered the chromatographic purification of an ON crude prepared by chemical synthesis using anion exchange resins. We demonstrate that in this system the competitive adsorption of the various species on the same sites of the resin leads to the displacement of the more weakly adsorbing species by the more strongly adsorbing ones. This phenomenon affects the behavior of the chromatographic units and it has been investigated in detail. Then, we developed a continuous countercurrent solvent gradient purification (MCSGP) process, which can significantly improve the productivity and buffer consumption compared to a classical single-column, batch chromatographic process.


Assuntos
Produtos Biológicos , Oligonucleotídeos , Distribuição Contracorrente/métodos , Solventes/química , Estados Unidos
8.
Int J Pharm ; 607: 120956, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34333024

RESUMO

Nowadays, the treatment of health care-associated infections represents a serious issue, due to the increasing number of bacterial strains resistant to traditional antibiotics. The use of antiseptics like quaternary ammonium salts and biguanides is a viable alternative to face these life-threatening infections. However, their inherent toxicity as well as the necessity of providing a sustained release to avoid the formation of pathogen biofilms are compelling obstacles towards their assessment in the hospitals. Within this framework, the role of polymeric drug delivery systems is fundamental to overcome the aforementioned problems. Biocompatibility, biodegradability and excipient-drug interactions are crucial properties determining the efficacy of the formulation. In this work, we provide an in-depth analysis of the polymer drug delivery systems that have been developed or are under development for the sustained release of positively charged antiseptics, highlighting the crucial characteristics that allowed to achieve the most relevant therapeutic effects. We reported and compared natural occurring polymers and synthetic carriers to show their pros and cons and applicability in the treatment of health care-associated infections. Then, the discussion is focused on a particularly relevant class of materials adopted for the scope, represented by polyesters, which gave rise, due to their biodegradability, to the field of resorbable drug delivery devices. Finally, a specific analysis on the effect of the polymer functionalization over the formulation performances for the different types of polymeric carriers is presented.


Assuntos
Anti-Infecciosos Locais , Excipientes , Atenção à Saúde , Sistemas de Liberação de Medicamentos , Polímeros
9.
Nanomaterials (Basel) ; 11(7)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203263

RESUMO

Reactive microgliosis is a pathological hallmark that accompanies neuronal demise in many neurodegenerative diseases, ranging from acute brain/spinal cord injuries to chronic diseases, such as amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD) and age-related dementia. One strategy to assess and monitor microgliosis is to use positron emission tomography (PET) by exploiting radioligands selective for the 18 kDa translocator protein (TSPO) which is highly upregulated in the brain in pathological conditions. Several TSPO ligands have been developed and validated, so far. Among these, PBR28 has been widely adopted for PET imaging at both preclinical and clinical levels, thanks to its high brain penetration and high selectivity. For this reason, PBR28 represents a good candidate for functionalization strategies, where this ligand could be exploited to drive selective targeting of TSPO-expressing cells. Since the PBR28 structure lacks functional moieties that could be exploited for derivatization, in this work we explored a synthetic pathway for the synthesis of a PBR28 derivative carrying an alkyne group (PBR-alkyne), enabling the fast conjugation of the ligand through azide-alkyne cycloaddition, also known as click-chemistry. As a proof of concept, we demonstrated in silico that the derivatized PBR28 ligand maintains the capability to fit into the TSPO binding pocked, and we successfully exploited PBR-alkyne to decorate zwitterionic biodegradable polymer nanoparticles (NPs) resulting in efficient internalization in cultured microglia-like cell lines.

10.
Polymers (Basel) ; 13(7)2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33810300

RESUMO

Thermo-responsive nanoparticles (NPs), i.e., colloids with a sharp and often reversible phase separation in response to thermal stimuli, are coming to the forefront due to their dynamic behavior, useful in applications ranging from biomedicine to advanced separations and smart optics. What is guiding the macroscopic behavior of these systems above their critical temperature is mainly the microstructure of the polymer chains of which these NPs are comprised. Therefore, a comprehensive understanding of the influence of the polymer properties over the thermal response is highly required to reproducibly target a specific behavior. In this study, we synthesized thermo-responsive NPs with different size, polymeric microstructure and hydrophilic-lipophilic balance (HLB) and investigated the role of these properties over their phase separation. We first synthesized four different thermo-responsive oligomers via Reversible Addition-Fragmentation Chain Transfer (RAFT) Polymerization of poly(ethylene glycol)methyl ether methacrylate. Then, exploiting the RAFT living character, we chain-extended these oligomers with butyl methacrylate obtaining a library of NPs. Finally, we investigated the NP thermo-responsive behavior, their physical state above the cloud point (Tcp) as well as their reversibility once the stimulus is removed. We concluded that the solid content plays a minor role compared to the relative length of the two blocks forming the polymer chains. In particular, the longer the stabilizer, the more favored the formation of a gel. At the same time, the reversibility is mainly achieved at high HLB, independently from the absolute lengths of the block copolymers.

11.
Nanoscale ; 13(18): 8543-8554, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33908992

RESUMO

In the last few decades, Pickering emulsions have regained attention due to the possibility of forming stable oil-in-water emulsions with interesting interfacial properties. As an example, the more and more stringent regulations on the products for home and personal care are pushing the market towards the use of biodegradable materials in order to reduce their environmental impact. In this scenario, an appealing opportunity is offered by the use of biodegradable polymeric nanoparticles (NPs) for the stabilization of fragrance oils in water. In this work, modular biodegradable NPs have been synthesized through a combination of ring opening polymerization and reversible addition-fragmentation chain transfer emulsion polymerization and used to produce limonene-in-water Pickering emulsions. This strategy allowed controlling independently the NP size, polymer molecular weight, and hydrophobicity acting on the microstructure of the constituting copolymers. Stable limonene-in-water Pickering emulsions could be obtained, with the size of the oil phase and the wetting by limonene that can be strictly controlled by tuning the NP physico-chemical properties. Finally, the adoption of thermo-responsive polymer chains within the shell of the Pickering emulsifiers enabled the on-demand destabilization of the emulsions and hence the selective dispensing of limonene by simply increasing the temperature.


Assuntos
Nanopartículas , Água , Emulsões , Limoneno , Óleos
12.
Biotechnol Bioeng ; 118(9): 3420-3434, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33755192

RESUMO

The increasing demand for efficient and robust processes in the purification of monoclonal antibodies (mAbs) has recently brought frontal chromatography to the forefront. Applied during the polishing step, it enables the removal of high molecular weight aggregates from the target product, achieving high purities. Typically, this process is operated in batch using a single column, which makes it intrinsically subjected to a purity-yield tradeoff. This means that high purities can only be achieved at the cost of lowering the product yield and vice versa. Recently, a two-column continuous implementation of frontal chromatography, referred to as Flow2, was developed. Despite being able of alleviating the purity-yield tradeoff typical of batch operations, the increase in the number of process parameters complicates its optimal design, with the risk of not exploiting its full potential. In this study, we developed an ad hoc design procedure (DP) suitable for the optimization of both batch frontal chromatography and Flow2 in terms of purity, yield, and productivity. This procedure provided similar results as a multiobjective optimization based on genetic algorithm but with lower computational effort. Then, batch and Flow2 operated at their optimal conditions were compared. Besides showing a more favorable Pareto front of yield and productivity at a specified purity, the Flow2 process demonstrated improved robustness compared to the batch process with respect to modifications in the loading linear velocity, washing buffer ionic strength and loading time, thus providing an appealing operation for integrated processes.


Assuntos
Anticorpos Monoclonais , Proteína Estafilocócica A/química , Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Cromatografia de Afinidade , Cromatografia por Troca Iônica
13.
Trends Analyt Chem ; 132: 116051, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32994652

RESUMO

Single-column (batch) preparative chromatography is the technique of choice for purification of biotherapeutics but it is often characterized by an intrinsic limitation in terms of yield-purity trade-off, especially for separations containing a larger number of product-related impurities. This drawback can be alleviated by employing multicolumn continuous chromatography. Among the different methods working in continuous mode, in this paper we will focus in particular on Multicolumn Countercurrent Solvent Gradient Purification (MCSGP) which has been specifically designed for challenging separations of target biomolecules from their product-related impurities. The improvements come from the automatic internal recycling of the impure fractions inside the chromatographic system, which results in an increased yield without compromising the purity of the pool. In this article, steps of the manufacturing process of biopharmaceuticals will be described, as well as the advantages of continuous chromatography over batch processes, by particularly focusing on MCSGP.

14.
Small ; 16(40): e2001207, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32893464

RESUMO

The confinement of organic synthesis within waterborne nanoreactors is regarded with increasing attention to improve its yield and reduce the environmental impact. However, many catalysts, such as graphene, are barely dispersible in aqueous media and many chemical reactions cannot be performed in the presence of water due to thermodynamic limitations. Therefore, there is an urgent need to develop novel strategies to carry out these processes in more sustainable conditions. To pursue this goal, in this work, a waterborne supramolecular nanoreactor is developed. The system comprises a polymeric micelle obtained from the self-assembly of pyrrole-based amphiphilic block copolymers. The active catalytic component is represented by few graphene layers, functionalized with pyrrole to enhance their interaction with the micelle core and hence their nanoencapsulation. Using this nanoreactor, it is possible to synthesize imines starting from primary amines and aldehydes or ketones with high yield and in short time (Y = 90% after 5 min) at room temperature. Moreover, an efficient strategy to recycle the reactor is proposed, thus increasing the potential of this technology.

15.
Biotechnol Adv ; 42: 107582, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32621947

RESUMO

The global pollution caused by plastics and microplastics is stimulating intense research towards more environmentally friendly materials, preserving the remarkable application characteristics of the currently available polymers. Among these, polyhydroxyalkanoates (PHAs) have been hailed as the solution to replace conventional, oil-based plastics. Given their biodegradable nature and mechanical properties, their use can be envisioned in a wide range of applications reducing the environmental footprint. Several types of processes have been proposed for their production, which can be grouped in three main classes: (i) microbiological, (ii) enzymatic and (iii) chemical processes. Given the significant amount of literature available on this topic, this review aims to critically analyse what has been proposed so far in each of these classes, with specific reference to their potential to provide bioplastics that can actually replace the currently available materials. A comparison is made, based on the following aspects: achievable molecular structures (such as molecular weight and composition distributions), raw-material and production costs and availability of large-scale production technologies. Finally, some considerations and ideas on what should be further investigated and implemented to realize the economically sustainable production of PHA are brought forward.


Assuntos
Poli-Hidroxialcanoatos , Biodegradação Ambiental , Plásticos
16.
J Pharm Sci ; 109(8): 2607-2614, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32422318

RESUMO

Biodegradable polymeric nanoparticles (NPs) are attracting increasing attention as carriers for drug delivery. However, one of the main factors limiting their transition to the market is their premature degradation and release of the payload during the storage. Therefore, for increasing the formulation shelf-life, the removal of water is of paramount importance. In this work, we synthesized both polyethylene glycol (PEG)-stabilized and zwitterionic NPs via Reversible Addition Fragmentation Chain Transfer (RAFT) Polymerization. We demonstrated that lyophilization leads the PEGylated NPs to irreversible aggregation, while the stability of the zwitterionic NPs was preserved only using a cryoprotectant. Therefore, we developed an alternative method for the NP concentration, based on the dialysis against a concentrated PEG solution. This method was optimized in terms of concentration factor (Fc), the ratio between the final and initial NP concentration, by acting on the PEG concentration in the dialysis medium, on its volume and on the initial NP concentration. With this approach, Fc up to 40 can be achieved in less than 10 h, preserving the possibility of redispersing the NPs to their original particle size distribution. Therefore, the dialysis proposed herein is a valuable alternative to lyophilization for the concentration of polymer NPs preserving their stability.


Assuntos
Nanopartículas , Polímeros , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Liofilização , Tamanho da Partícula , Polietilenoglicóis , Diálise Renal
17.
Biotechnol J ; 15(8): e1900226, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32298041

RESUMO

Oligonucleotides (ONs) are gaining increasing importance as a promising novel class of biopharmaceuticals. Thanks to their fundamental role in gene regulation, they can be used to develop custom-made drugs (also called N-to-1) able to act on the gene expression at pre-translational level. With recent approvals of ON-based therapeutics by the Food and Drug Administration (FDA), a growing demand for high-quality chemically modified ONs is emerging and their market is expected to impressively prosper in the near future. To satisfy this growing market demand, a scalable and economically sustainable ON production is needed. In this paper, the state of the art of the whole ON production process is illustrated with the aim of highlighting the most promising routes toward the auspicated market-size production. In particular, the most recent advancements in both the upstream stage, mainly based on solid-phase synthesis and recombinant technology, and the downstream one, focusing on chromatographic techniques, are reviewed. Since ON production is projected to expand to the large scale, automatized multicolumn countercurrent technologies will reasonably be required soon to replace the current ones based on batch single-column operations. This consideration is supported by a recent cutting-edge application of continuous chromatography for the ON purification.


Assuntos
Biotecnologia , Oligonucleotídeos , Produtos Biológicos , Biotecnologia/tendências , Cromatografia , Distribuição Contracorrente , Oligonucleotídeos/biossíntese , Oligonucleotídeos/química , Oligonucleotídeos/isolamento & purificação , Oligonucleotídeos/uso terapêutico , Estados Unidos , United States Food and Drug Administration
18.
Colloids Surf B Biointerfaces ; 190: 110926, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32155458

RESUMO

Synthetic polymers are attracting growing attention as additives for laundry and personal care products. In particular, the high volatility of many common fragrances requires the development of polymeric particles for their encapsulation and controlled release. Unfortunately, the vast majority of these carriers is made from polymers that are not biodegradable. This poses severe concerns about the accumulation of nano- and microplastics. Hence, such particles are expected to be banned from the market in the coming years. Therefore, biodegradable particles enabling a long-lasting release of the fragrances are urgently needed. In this work, we produced biodegradable nanoparticles (NPs) that are structurally composed of lactones, i.e. well known perfumes that occur naturally and that are already considered safe by regulatory agencies. We polymerized these lactones via ring opening polymerization (ROP) using an ionizable tertiary amine as initiator to produce in a single step amphiphilic oligoesters able to directly self-assemble into NPs once nanoprecipitated in water. In this way, we can produce biodegradable NPs with a perfume loading up to 85 % w/w without the need for additional surfactants. Subsequently we show that the ionizable group is able to confer a positive charge to our nanoparticles and, in turn, a high adsorption capacity on natural fibers (i.e. hairs and cotton fabric). Finally, we demonstrate the nanoparticle resistance to rinsing and their ability to confer a long-lasting fragrance perception to treated hair swatches for at least 3 weeks.


Assuntos
Fibra de Algodão , Cabelo/química , Lactonas/química , Nanopartículas/química , Adsorção , Aminas/química , Humanos , Lactonas/síntese química , Estrutura Molecular , Tamanho da Partícula , Polimerização , Propriedades de Superfície , Tensoativos/química
19.
ACS Biomater Sci Eng ; 6(9): 5337-5345, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-33455282

RESUMO

The efficacy of several cell therapy products is directly impacted by trypsinization, which can diminish the engrafting capacity of transplanted cells by cleaving cell surface receptors. Thermoresponsive surfaces can alleviate this drawback, enabling temperature-driven and enzyme-free cell harvesting. However, the production of thermoresponsive surfaces relies on dedicated and complex equipment, often involving protocols dependent on high surface activation energies that prevent the development of scalable and universal platforms. In this work, we developed thermoresponsive copolymers incorporating styrene units that enable the copolymer adsorption on tissue culture polystyrene surfaces from an alcoholic solution in a short time, regardless of the vessel size and geometry, and without any particular equipment. In this way, the procedure can be performed with minimal effort by the end user on any surface. The thermoresponsive copolymers were synthesized via reversible addition-fragmentation chain transfer polymerization, providing high control over the polymer microstructure, a key parameter for tuning its cloud point and architecture. Block copolymers comprising a thermoresponsive segment and a polystyrene block exhibited optimal adhesion on conventional cell culture surfaces and permitted a more efficient temperature-mediated harvesting of adipose-derived stromal cells and Chinese hamster ovary cells compared to their statistical counterparts. To expand the application of this polymer deposition protocol to serum-free cell culture, we also considered the polymer modification with the tripeptide arginine-glycine-aspartic acid, known to promote the cell adhesion to synthetic substrates. The incorporation of this peptide enabled the collection in serum-free conditions of intact cell sheets from surfaces prepared shortly before their usage.


Assuntos
Polímeros , Animais , Células CHO , Adesão Celular , Cricetinae , Cricetulus , Polimerização
20.
ACS Nano ; 14(1): 360-371, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31887011

RESUMO

Astrogliosis has a very dynamic response during the progression of spinal cord injury, with beneficial or detrimental effects on recovery. It is therefore important to develop strategies to target activated astrocytes and their harmful molecular mechanisms so as to promote a protective environment to counteract the progression of the secondary injury. The challenge is to formulate an effective therapy with maximum protective effects, but reduced side effects. In this study, a functionalized nanogel-based nanovector was selectively internalized in activated mouse or human astrocytes. Rolipram, an anti-inflammatory drug, when administered by these nanovectors limited the inflammatory response in A1 astrocytes, reducing iNOS and Lcn2, which in turn reverses the toxic effect of proinflammatory astrocytes on motor neurons in vitro, showing advantages over conventionally administered anti-inflammatory therapy. When tested acutely in a spinal cord injury mouse model, it improved motor performance, but only in the early stage after injury, reducing the astrocytosis and preserving neuronal cells.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Astrócitos/efeitos dos fármacos , Nanogéis/química , Rolipram/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Células Cultivadas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Rolipram/administração & dosagem , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/cirurgia , Propriedades de Superfície
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