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1.
Soft Matter ; 18(26): 4963-4972, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35748523

RESUMO

Herein, we describe the design and synthesis of a new variety of bio-based hydrogel films using a Cu(I)-catalyzed photo-click reaction. These films exhibited thermal-triggered swelling-deswelling and were constructed by crosslinking a triazide derivative of glycerol ethoxylate and dialkyne structures derived from isosorbide, a well-known plant-based platform molecule. The success of the click reaction was corroborated through infrared spectroscopy (FTIR) and the smooth surface of the obtained films was confirmed by scanning electron microscopy (SEM). The thermal characterization was carried out in terms of thermogravimetry (TGA) and differential scanning calorimetry (DSC), from which the decomposition onset and glass transition temperatures were determined, respectively. Additionally, mechanical properties of the samples were estimated by stress-strain experiments. Then, their swelling and deswelling properties were systematically examined in PBS buffer, revealing a thermoresponsive behavior that was successfully tested in the release of the anticancer drug doxorubicin. We also confirmed the non-cytotoxicity of these materials, which is a fundamental aspect for their potential use as drug carriers or tissue engineering matrices.


Assuntos
Hidrogéis , Isossorbida , Biomassa , Varredura Diferencial de Calorimetria , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
2.
Chempluschem ; 86(12): 1570-1576, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34851049

RESUMO

This work reports a simple and scalable strategy to prepare a series of thermoresponsive polyurethanes synthesized via copolymerization of dicyclohexyl diisocyanate with glycerol ethoxylate in a single one-pot system. These polyurethanes exhibit lower critical solution temperatures (LCST) at 57 °C. The LCST of synthesized polyurethane was determined from Dynamic Scanning Calorimetry and UV-vis measurements. Both the LCST and Tg of synthesized polyurethane was tuned by varying the ratio between hard segment (dicyclohexyl diisocyanate) and soft segment (glycerol ethoxylate). Thus, Tg values could be tuned from -54.6 °C to -19.9 °C for samples with different flexibility. The swelling and deswelling studies were done at room temperature and above the LCST respectively. The results showed that the swelling ratio increases with the increase of soft segment (glycerol ethoxylate) in synthesized polyurethanes. Furthermore, the mechanical properties of the membrane were studied by universal tensile testing measurements. Specifically, stress at break values varied from 0.35±0.07 MPa to 0.91±0.15 MPa for the tested membranes, whereas elongation at break data ranged from 101.9±20.9 % to 192.4±24.4 %, and Young's modulus varied from 0.35±0.03 MPa to 1.85±0.19 MPa. Tensile strength of the films increased with the increase of the hard segment and elongation at break decreased.

3.
Soft Matter ; 17(12): 3314-3321, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33629701

RESUMO

Pharmacological chaperones (PCs) are low-molecular weight chemical molecules used in patients for the treatment of some rare diseases caused primarily by protein instability. A controlled and on-demand release of PCs via nanoparticles is an alternative for cases in which long treatments are needed and prolonged oral administration could have adverse effects. In this work, pyrimethamine (PYR), which is a potent PC consisting of pyrimidine-2,4-diamine substituted at position 5 by a p-chlorophenyl group and at position 6 by an ethyl group, was successfully loaded in electroresponsive poly(3,4-ethylenedioxythiophene) nanoparticles (PEDOT NPs). The PYR-loading capacity was 11.4 ± 1.5%, with both loaded and unloaded PEDOT NPs exhibiting similar sizes (215 ± 3 and 203 ± 1 nm, respectively) and net surface charges (-26 ± 7 and -29 ± 6 mV, respectively). In the absence of electrical stimulus, the release of PC from loaded NPs is very low (1.6% in 24 h and 18% in 80 days) in aqueous environments. Instead, electrical stimuli that sustained for 30 min enhanced the release of PYR, which was ∼50% when the voltage was scanned from -0.5 V to 0.5 V (cyclic voltammetry) and ∼35% when a constant voltage of 1.0 V was applied (chronoamperometry).


Assuntos
Nanopartículas , Polímeros , Administração Oral , Preparações de Ação Retardada , Humanos
4.
Adv Healthc Mater ; 10(7): e2001636, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33336558

RESUMO

Conducting polymers have been increasingly used as biologically interfacing electrodes for biomedical applications due to their excellent and fast electrochemical response, reversible doping-dedoping characteristics, high stability, easy processability, and biocompatibility. These advantageous properties can be used for the rapid detection and eradication of infections associated to bacterial growth since these are a tremendous burden for individual patients as well as the global healthcare system. Herein, a smart nanotheranostic electroresponsive platform, which consists of chloramphenicol (CAM)-loaded in poly(3,4-ethylendioxythiophene) nanoparticles (PEDOT/CAM NPs) for concurrent release of the antibiotic and real-time monitoring of bacterial growth is presented. PEDOT/CAM NPs, with an antibiotic loading content of 11.9 ± 1.3% w/w, are proved to inhibit the growth of Escherichia coli and Streptococcus sanguinis due to the antibiotic release by cyclic voltammetry. Furthermore, in situ monitoring of bacterial activity is achieved through the electrochemical detection of ß-nicotinamide adenine dinucleotide, a redox active specie produced by the microbial metabolism that diffuse to the extracellular medium. According to these results, the proposed nanotheranostic platform has great potential for real-time monitoring of the response of bacteria to the released antibiotic, contributing to the evolution of the personalized medicine.


Assuntos
Nanopartículas , Polímeros , Antibacterianos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes , Humanos , Nanomedicina Teranóstica
5.
Macromol Biosci ; 20(7): e2000074, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32449596

RESUMO

Simultaneous drug release and monitoring using a single polymeric platform represents a significant advance in the utilization of biomaterials for therapeutic use. Tracking drug release by real-time electrochemical detection using the same platform is a simple way to guide the dosage of the drug, improve the desired therapeutic effect, and reduce the adverse side effects. The platform developed in this work takes advantage of the flexibility and loading capacity of hydrogels, the mechanical strength of microfibers, and the capacity of conducting polymers to detect the redox properties of drugs. The engineered platform is prepared by assembling two spin-coated layers of poly-γ-glutamic acid hydrogel, loaded with poly(3,4-ethylenedioxythiophene) (PEDOT) microparticles, and separated by a electrospun layer of poly-ε-caprolactone microfibers. Loaded PEDOT microparticles are used as reaction nuclei for the polymerization of poly(hydroxymethyl-3,4-ethylenedioxythiophene) (PHMeDOT), that semi-interpenetrate the whole three layered system while forming a dense network of electrical conduction paths. After demonstrating its properties, the platform is loaded with levofloxacin and its release monitored externally by UV-vis spectroscopy and in situ by using the PHMeDOT network. In situ real-time electrochemical monitoring of the drug release from the engineered platform holds great promise for the development of multi-functional devices for advanced biomedical applications.


Assuntos
Monitoramento de Medicamentos , Eletricidade , Hidrogéis/química , Bactérias/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Liberação Controlada de Fármacos , Levofloxacino/farmacologia , Testes de Sensibilidade Microbiana , Poliésteres/química , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/química , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria
6.
Macromol Biosci ; 19(8): e1900130, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31222941

RESUMO

Ambroxol is a pharmacological chaperone (PC) for Gaucher disease that increases lysosomal activity of misfolded ß-glucocerebrosidase (GCase) while displaying a safe toxicological profile. In this work, different poly(ε-caprolactone) (PCL)-based systems are developed to regulate the sustained release of small polar drugs in physiological environments. For this purpose, ambroxol is selected as test case since the encapsulation and release of PCs using polymeric scaffolds have not been explored yet. More specifically, ambroxol is successfully loaded in electrospun PCL microfibers, which are subsequently coated with additional PCL layers using dip-coating or spin-coating. The time needed to achieve 80% release of loaded ambroxol increases from ≈15 min for uncoated fibrous scaffolds to 3 days and 1 week for dip-coated and spin-coated systems, respectively. Furthermore, it is proven that the released drug maintains its bioactivity, protecting GCase against induced thermal denaturation.


Assuntos
Ambroxol/química , Preparações de Ação Retardada/química , Glucosilceramidase/química , Poliésteres/química , Substâncias Protetoras/química , Ambroxol/farmacologia , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Técnicas Eletroquímicas , Temperatura Alta , Cinética , Substâncias Protetoras/farmacologia , Dobramento de Proteína/efeitos dos fármacos , Estabilidade Proteica
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