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1.
Carbohydr Polym ; 237: 116138, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32241433

RESUMO

Schiff base reaction crosslinking hydrogels are advantageous by rapid formation and absence of external crosslinkers. However, poor mechanical hindered their broader applications. Here, a mechanically strengthened tissue adhesive was constructed through incorporation of chitin nano-whiskers (CtNWs) with a Schiff base crosslinking hydrogel of carboxymethyl chitosan (CMCS) and dextran dialdehyde (DDA). The optimal formulation of complexed hydrogel exhibited 1.87 folds higher compressive stress than non-complexed and 1.51 time higher adhesive strength on porcine skin. The complexed hydrogel exhibited negligible cytotoxicity, anti-swelling performance in PBS, optimum antibacterial and hemostatic capacities. In vivo implantation studies confirmed the complexed hydrogel was degradable without long-term inflammatory responses. Desirable efficacy of injectable complexed hydrogel as hemostat was demonstrated in rat liver injury model, which could avoid severe postoperative adhesion and necrosis as observed in the treatment with commercial 3 M™ vetbond™ tissue adhesive. The results highlighted that the complexed hydrogel potentiated rapid hemostasis and wound repair applications.

2.
Biomacromolecules ; 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32202418

RESUMO

Chitosan (CS), a natural biopolymer, has been extensively explored for multiple applications including tissue engineering, gene therapy, bioimaging, and sewage treatment due to its abundant availability, intrinsic biocompatibility, biodegradability, and tunable biological properties. Nevertheless, the actual use of CS is limited because of its water-insolubility in physiological circumstances, which could be optimized by chemical modifications via active side groups. Etherification is one of the most widely used reactions to obtain water-soluble CS derivatives, such as hydroxybutyl CS (HBC). HBC, synthesized by grafting hydroxybutyl groups to the functional hydroxyl and amino groups of CS skeleton, has been demonstrated to possess superior biological properties over those of CS, especially satisfactory water solubility in neutral condition and reversible stimulus-response against external heat. Meanwhile, the unique characteristics of thermally sensitive "sol-gel" and "sol-micelle" transition have gained tremendous attention, which differ in heterogeneously and homogeneously synthesized HBC. Herein, we discuss the synthesis (heterogeneously and homogeneously) of HBC, favorable physiochemical properties of HBC, and HBC-centered biocomposites in a range of formulations or dosage forms such as sponges, gels, nanoparticles, nanofibers, and films. Meanwhile, we summarize the potential bioapplications and trends of HBC and HBC centered biocomposites and offer our perspectives on the plausible advances in this field in the near future.

3.
Carbohydr Polym ; 236: 116051, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172865

RESUMO

Effective bleeding control is critical first step in current civilian and military trauma treatment, however commercially available hemostatic materials are difficult to achieve expected effects. In this study, a composite sponge (H-D) based on hydroxybutyl chitosan (HBC) and diatom-biosilica (DB) was designed for hemorrhage control. H-D exhibited hierarchical porous structure, favorable biocompatibility (hemolysis ratio < 5 %, no cytotoxicity), along with high and fast fluid absorbability (11-16 times than that of weight), given effective hemostasis effect (clotting time shortened by 70 % than that of control). In vitro coagulation tests demonstrated that H-D could provide strong interface effect to induce erythrocyte absorption and aggregation, as well as activating the intrinsic coagulation pathway and thus accelerated blood coagulation. These results proved that H-D composite sponge has great potential for hemorrhage control.

4.
Carbohydr Polym ; 236: 116067, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172882

RESUMO

Stimuli-responsive gel volume variation is reversible and has shown promising applications, which may be potential for contraction or expansion fabrication, generating shrinking or swelling volume of the original. In this study, a thermo/photo dual-crosslinking hydrogel is prepared with methacrylated hydroxylbutyl chitosan (MHBC) and gelatin methacrylate (GelMA). The M/G hydrogel undergoes sol-gel phase transition under room temperature and shrinking deformation upon elevating temperature. Besides nontoxicity and biodegradability, dual crosslink endowed the composite hydrogel with strengthened and tunable mechanical property, controlled and repeatable contraction property in response to temperature elevation from 25 ℃ to 37 ℃, and enhanced cell adhesion in 3D culture. These peculiarities of M/G hydrogel provide great potential for application in contraction fabrication to acquire high resolution or small scale features that may be limited by fabrications devices.

5.
Int J Biol Macromol ; 154: 758-764, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32171832

RESUMO

Alkali/urea, a green dissolution system for chitosan, have been widely used in preparation of chitosan-derived materials. However, there are no related reports detail the structure stability and biocompatibility of chitosan in alkali/urea, which are important for its large-scale application. In this work, chitosan was dissolved in KOH/urea solution and stored at different temperature for different time. The structure, viscosity, molecule weight (Mw), degree of deacetylation (DD), and biocompatibility of chitosan were determined. The Mw of chitosan decreased from 1011 KDa to 827-834 KDa, and DD increased from 76.9% to 85.7-93.5% after been stored at 25 °C and 4 °C for 5 weeks. Incomplete dissolution of chitosan and increase of DD enhanced its thermal stability by forming new crystallization zone. In contrast, chitosan stored in -20 °C for 5 weeks was stable without obvious change of Mw and DD. Moreover, the processed chitosans were no-toxic and safety for the biomedicine applications.

6.
Int J Biol Macromol ; 154: 433-445, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32194103

RESUMO

The oral drug administration was convenient and comfortable route for patients. Nevertheless, the oral uptake efficiency of many therapeutic agents was limited by physiological barriers of the gastrointestinal (GI) tract. This review summarized the challenges toward the oral delivery systems including instability and poor permeability in gastrointestinal environment. The transcellular and paracellular transport were main pathways of nanocarriers across intestinal epithelium. Chitosan is a nature and safe polymer that possesses the capacity of opening intercellular tight junctions of epithelium and excellent mucoadhesive property. Chitosan-based nanocarriers have recently attracted considerable attentions, aiming to overcome GI limitations and enhance drug absorption. Recently developed chitosan-based nanocarriers administered via oral route were highlighted for protecting drugs against degradation, releasing drugs in small intestine, enhancing drug uptake, thus improving oral bioavailability. Finally, various biotherapeutics including hydrophobic and hydrophilic drugs applied in chitosan-based nanovectors were also reviewed.

7.
Mater Sci Eng C Mater Biol Appl ; 108: 110419, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924016

RESUMO

Hydrogels have been widely utilized in various fields as a function of their tunable physical and biochemical properties. The unique physical properties of hydrogels, including their porosity and swelling capacity, make them favorable platforms for drug delivery. Although chitosan is the most popular natural polymer due to its biocompatibility, low toxicity, biodegradability, and other biofunctional activities, its potential commercial applications are constrained due to its poor solubility in water. Hydroxybutyl chitosan (HBCS) was synthesized in our study to improve its solubility. The HBCS hydrogel exhibited excellent thermo/pH sensitive sol-gel reversibility behavior from 4 °C to the gelation temperature. Additionally, the gelation time and temperature could be optimized by adjusting the HBCS concentration, gelation temperature, and pH value according to clinical requirements. The HBCS hydrogel had both favorable water-solubility and swellability when compared with unmodified chitosan. Moreover, the HBCS demonstrated lower hemolysis at a concentration of 1 mg/mL. The HBCS hydrogel was completely biodegraded after 8 weeks of muscle implantation and 7 weeks of subcutaneous implantation. These results demonstrated that the HBCS hydrogel with biodegradable thermo/pH sensitive sol-gel reversible properties had excellent cytocompatibility, histocompatibility, and biocompatibility as a drug carrier. As such, HBCS holds great promise for future biomedical applications.

8.
Langmuir ; 36(4): 966-971, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31941280

RESUMO

Dielectric spectroscopy has unique advantages in monitoring drug release. In this work, a dielectric measurement was carried out on the release of the substances of microcapsule-immobilized composite capsules, which were fabricated by encapsulating the Perinereis aibuhitensis extract-loaded gum Arabic/gelatin microcapsules (PaE: GA/GE-MCs) in calcium alginate hydrogel (PaE: CA/GA/GE-CCs). We established the dielectric model of PaE: CA/GA/GE-CCs and got in-depth information on the systems. There are two relaxations in the dielectric spectroscopy, both of which are caused by interfacial polarization. The relaxation mechanisms correspond to the interfacial polarization of the PaE-loading core/calcium alginate shell interface and the calcium alginate shell/solution interface, respectively. Besides, the swelling of composite capsules and substance migration in the composite capsules were observed by analyzing phase parameters. Finally, the characteristic release of calcium alginate composite capsules was confirmed, and the substance release mechanism of composite capsules, namely, the swelling-diffusion mechanism, was obtained.

9.
Carbohydr Polym ; 229: 115557, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826433

RESUMO

Chitosan (CS) based self-assembled nanohydrogels are considered as promising platform for biomedicine, petrochemical, agricultural and food applications due to their unique biodegradability, nano-interface effect, and intelligent responsiveness. However, the most CS derivatives are prepared in heterogeneous system, which is unstable and environmentally unfriendly. In this work, a series of hydroxybutyl chitosan (HBC) was synthesized based on a green and homogeneous system (potassium hydroxide (KOH)/urea), which given this derivative interesting temperature responsive phase transformation behavior. HBC could change from dissolved state into nanohydrogel state in deionized water, when the temperature exceed its critical phase change temperature, and this process could be repeated more than 50 cycles (one cycle/day) without coagulation. The nanohydrogels solution exhibited concentration and temperature-dependent ultraviolet absorption and visible light regulation, which had great application potential in smart windows. This study provided a novel preparation method and extended the application of chitosan-based temperature responsive self-assembled nanohydrogels.

10.
Int J Biol Macromol ; 146: 99-109, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31874265

RESUMO

Biocompatibility and mechanical properties have always been important indicators for the application of hydrogel materials in tissue engineering. In this work, a high strength and toughness chitosan-poly (vinyl alcohol) (PVA) DN (double network) hydrogel based on multiple hydrogen bonding interactions was prepared by applying the simple freezing-heating alternate treatment to the chitosan-PVA alkaline solution. The PVA first network was prepared by freeze crystallization, and the chitosan second network was constructed by raising the chitosan/KOH/urea temperature to 45 °C. The dynamic hydrogen bonding presented in the first PVA network and the second chitosan network given the hydrogel superior compressive (60%-230 KPa), tensile (152 KPa-360%), recoverability (90.77% after 5 cycles) and anti-swelling properties. The results of in vitro cell compatibility and in vivo subcutaneous implantation in rats both indicated that the chitosan-PVA DN hydrogel had the ability to promote cell attachment and wound healing. This DN hydrogel based on hydrogen bonding is expected to be applied in the tissue engineering repair. In addition, the hydrogel preparation process is simple and non-toxic, which provides a reference for the production of green and safe tissue engineering hydrogels.

11.
Int J Biol Macromol ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31739062

RESUMO

The effect of NaOH/urea solution freeze-thaw pretreatment to the chitosan of purity and the degree of deacetylation from the crab shell was examined. Higher purity chitosan (CS1) was prepared. On this basis, the raw materials after the first demineralization were pretreated with NaOH/urea solution freeze-thaw under different freeze-thaw situations. The produced chitosans (CS1-CS4) were characterized in the ash content, solubility, protein content, degree of deacetylation, viscosity average molecular weight, SEM, FTIR, XRD, antimicrobial activity. The results showed that the freeze-thaw process had advantageous influence on decreasing the ash content and increasing degree of deacetylation and antibacterial activity. Moreover, the antibacterial property of the extracted chitosans seemed to be positively related to their degree of deacetylation. It is concluded that CS4 had the lowest ash content (0.052%), the highest degree of deacetylation (86.02%) and the greatest antibacterial activity. Therefore, we recommend CS4 as agent for industrial and pharmaceutical applications.

12.
Life Sci ; 239: 117042, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715186

RESUMO

AIMS: ZBTB7A, a transcriptional repressor, accelerates the breast cancer progression. Over 70% of breast cancer samples are identified as ER-α positive. Due to the function of ZBTB7A in ER-α positive breast cancer incompletely known, we aimed to determine the role of ZBTB7A in ER-α positive cancer and explore the underlying mechanisms. MAIN METHODS: In this study, the correlation between ZBTB7A and ER-α was confirmed by tissue microarray-based and TCGA database. Then, we explore if ZBTB7A maintains ER-α's level via targeting ER-α's expression or degradation. Finally, we examined the effect of ZBTB7A on the proliferation of breast cancer cells. KEY FINDINGS: We further confirmed that ZBTB7A shows a significant positive correlation with ER-α in clinical breast cancer samples by tissue microarray-based analysis. Mechanically, we identified that the inhibition of ZBTB7A could upregulate E3 ligase TRIM25 leading to enhancement of ER-α ubiquitination and proteasomal degradation, which could partly explain the correlation between ZBTB7A and ER-α. Besides, we uncovered that ZBTB7A could also transcriptionally increase the expression of ER-α via indirectly binding to the region +146 to +461 bp downstream of the transcription start site of ESR1 (ERpro315) in breast cancer cells. Furthermore, ZBTB7A is found to stimulate the expression of ER-α's downstream genes, and promote the growth of estrogen receptor alpha (ER-α)-positive breast cancer cells. SIGNIFICANCE: Our data revealed the novel mechanisms through which ZBTB7A manipulates ER-α level and might provide a new avenue for endocrine therapy in breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Ligação a DNA/metabolismo , Receptor alfa de Estrogênio/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Proteínas de Ligação a DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Células MCF-7 , Transdução de Sinais/genética , Fatores de Transcrição/genética , Ativação Transcricional/genética , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Ubiquitinação
13.
Mater Sci Eng C Mater Biol Appl ; 105: 110086, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546413

RESUMO

Chitosan (CS) has been reported to have utility for various potential applications in biomedicine, tissue engineering, and cosmetics, as well as in the formulation of antibacterial agents because it exhibits a variety of desirable attributes, including low-toxicity, biodegradability, excellent biocompatibility, and broad-spectrum antibacterial activity. However, the full realization of CS's biomedical applications are practically constrained by its poor solubility. The goal of the present study is to prepare hydroxybutyl chitosan (HBCS) and investigate its impacts on immunocompetence, and its antibacterial activity. In the current study, HBCS was synthesized by modifying the hydroxybutyl group on the chitosan molecule using an etherification method. The physicochemical properties of the synthesized HBCS were characterized by various methods. Results showed that hydro-soluble HBCS exhibited excellent hygroscopicity and moisture retention. It was also found that HBCS exhibited notable cytocompatibility when cultured with mouse embryo fibroblasts. HBCS was able regulate immuno-functionality and promote immunocompetence by improving phagocytosis of macrophages and reinforcing lymphocyte activity in vivo and in vitro. Moreover, HBCS was also found to inhibit L-929 cell migration, indicating the impeded migration and metastasis behaviors of fibrosarcoma cells. Additionally, HBCS displayed favorable antimicrobial functionality against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. This study demonstrated that HBCS could in turn lock moisture, can promote immunocompetence activity, can inhibit fibrosarcoma cell migration, and exhibits anti-bacterial functionality. Taken together, these results indicate that HBCS shows substantial promise for applications in cosmetics, biomedicine, and antibacterial therapies.


Assuntos
Antibacterianos , Quitosana/análogos & derivados , Embrião de Mamíferos/imunologia , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/imunologia , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular Tumoral , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Camundongos Endogâmicos ICR
14.
Carbohydr Polym ; 224: 115176, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472871

RESUMO

Weak mechanical properties, lack biocompatibility and relatively bioinert are formidable obstruct in application of bone repair materials. Multifunctional composite materials have been considered as a viable solution to this problem. Here, a new double network (DN) hydrogel was constructed by physical cross-linking of medical grade poly (vinyl alcohol) (PVA) and chitosan in KOH/urea dissolution system. The obtained hydrogel demonstrated excellent tensile strength (0.24 MPa), elongation at break (286%), and high compressive strength (0.11 MPa on the strain of 60%). Our studies showed that the prepared hydrogel had excellent biocompatibility in vitro and the introduction of hydroxyapatite (HAp) by surface mineralization imparted hydrogel the ability to induce rat bone marrow stem cells (rBMSCs) differentiation. The in vivo experiments revealed that the surface mineralized double network hydrogel significantly accelerated simultaneous regeneration of bone defects in a rabbit bone defect model. All the results indicated that this hydrogel has the potential as a bone repair material.


Assuntos
Osso e Ossos/efeitos dos fármacos , Quitosana/química , Hidrogéis/química , Hidrogéis/farmacologia , Minerais/química , Álcool de Polivinil/química , Adsorção , Animais , Osso e Ossos/citologia , Osso e Ossos/fisiologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Força Compressiva , Hidróxidos/química , Osteogênese/efeitos dos fármacos , Compostos de Potássio/química , Coelhos , Soroalbumina Bovina/química , Propriedades de Superfície , Resistência à Tração , Engenharia Tecidual , Ureia/química
15.
Carbohydr Polym ; 223: 115072, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31427010

RESUMO

A novel pH-responsive nanomicelle (QT-CA-CS) based on Chitosan, Quercetin and Citraconic anhydride was reported in this study. The QT-CA-CS could self-assemble into nanomicelles for encapsulating anticancer drug doxorubicin (DOX) by ultrasound. The novel nanomicelles had P-gp inhibition and pH responsiveness, which was capable of inhibiting drug efflux and responding to an endo/lysosomal acidic environment. The drug loaded nanomicelles had high encapsulation rate (more than 80%), small particle size (133.52 ± 4.13 nm) and positive zeta potential (+13.5 mV). The release rate of doxorubicin and quercetin in pH 4.5 was faster than that in pH 7.4. QT-CA-CS-DOX nanomicelles could promote cellular uptake of doxorubicin by drug resistance cell line (MCF-7/ADR), which was 8.62 folds higher than that of free doxorubicin. Most importantly, QT-CA-CS-DOX nanomicelles could escape from lysosomes and rapidly release doxorubicin and quercetin in the cytoplasm, which had an enhanced inhibitory effect on tumor cells, especially for MCF-7/ADR. The above results proved that the high potential of QT-CA-CS-DOX nanomicelles for multidrug resistance related tumor therapy.


Assuntos
Antineoplásicos/farmacologia , Quitosana/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Quercetina/farmacologia , Tensoativos/química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Citometria de Fluxo , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Micelas , Estrutura Molecular , Imagem Óptica , Tamanho da Partícula , Quercetina/química , Propriedades de Superfície , Tensoativos/síntese química
16.
J Mater Chem B ; 7(31): 4854-4866, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31389952

RESUMO

The efficient delivery of vaccines to draining lymph nodes and the induction of robust local immune responses are crucial for immunotherapy. Transdermal administration has been evidenced to facilitate the delivery of ingredients to lymph nodes. In this study, transfersomes with opposite surface charges were applied for antigen encapsulation and these were integrated with dissolving microneedles to investigate their effects on immune responses via transdermal immunization. The microneedles were easily inserted into mouse skin and achieved the local release of nanovaccines into the dermis through dissolution. Although anionic nanovaccines promoted cellular uptake via DC2.4, cationic nanovaccines exhibited stronger escape capacities from endocytic compartments, facilitating antigen processing via an MHC-I presentation pathway, and formed larger accumulations in lymph nodes. Compared with their anionic counterparts, the cationic nanovaccines more efficiently activated DC maturation and induced Th1 immunity; this was suggested by the significantly increased IgG2a/IgG1 ratio and elevated cytokine secretion from Th1 cells, without an enhancement in the Th2 response. Such an enhanced Th1 antigen-specific immune response in lymph nodes via a transdermal vaccine delivery platform is beneficial for potential immunotherapy approaches.

17.
Int J Biol Macromol ; 139: 1035-1045, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412265

RESUMO

Colorectal cancer (CRC) is a prevalent and fatal cancer. Oral administration provided the potential for in situ treatment of the colorectal cancer. However, drugs couldn't be well-absorbed mainly due to its degradation in the gastric area and poor intestinal permeability. In this study, we synthesized deoxycholic acid and hydroxybutyl decorated chitosan nanoparticles (DAHBC NPs) as oral curcumin (CUR) delivery system for colorectal cancer treatment. DAHBC with lower critical solution temperature (LCST) below 37 °C (27-33 °C) was obtained. DAHBC NPs were correspondingly stable in simulated gastric conditions (pH 1.2, 37 °C), due to the offset of size change between pH-responsive expansion and thermo-responsive shrinkage. In simulated intestinal tract (pH 7.0-7.4, 37 °C), DAHBC NPs exhibited burst release of CUR owing to the onefold effect of thermo-responsive shrinkage. DAHBC27 NPs showed the minimum CUR leakage (~10%) in simulated gastric conditions, because a furthest temperature-sensitive shrinkage caused by the lowest LCST offset the expansion in acid environment. DAHBC27 NPs induced ~10-fold increased (P < 0.05) CUR absorption by paracellular transport pathway, compared to the free CUR. Thus, DAHBC NPs stabilized in the gastric environment may be a promising oral drugs delivery system for effective in situ colorectal cancer therapy.

18.
Int J Biol Macromol ; 138: 321-333, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31295499

RESUMO

The aim of this study was to develop an effective wound dressing using a temperature-responsive hydroxybutyl chitosan (HBC) based hydrogel. The HBC - chitosan (CS) - dopamine (HCS-DOPA) composite hydrogels were prepared by the dopamine self-polymerization at different concentrations (0, 0.5, 1.0 and 2.0 mg/mL), termed as HCS, HCS-DOPA-0.5, HCS-DOPA-1 and HCS-DOPA-2, respectively. The gelling characteristic of HBC hydrogel was not influenced by composite CS and DOPA. The HCS-DOPA composite hydrogels were non-cytotoxic to mouse fibroblast cells (L929), and induced under 5.0% hemolysis rate. In vitro antibacterial studies, composite HCS-DOPA-2 hydrogels exhibited lasting inhibition to S. aureus >8 h. The whole blood test in vitro demonstrated that blood clotting time treated with HCS-DOPA-2 composite hydrogels was shortened to 95.6 s compared with that of HCS in vitro hemostasis. The results suggested that HCS-DOPA-2 composite hydrogels could be applied as a promising wound dressing for hemostasis in vitro.


Assuntos
Bivalves , Quitosana/química , Hemostasia/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Indóis/química , Polímeros/química , Temperatura Ambiente , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Fenômenos Químicos , Escherichia coli/efeitos dos fármacos , Cinética , Staphylococcus aureus/efeitos dos fármacos
19.
Int J Biol Macromol ; 135: 1182-1192, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31154036

RESUMO

Allergic rhinitis (AR) was a chronic airway inflammatory disease. Nasal administration showed superiorities due to its effective drug absorption. Cetirizine (CTZ) was a common H1-antihistamine in allergic disorders therapy, while hydrophobicity and irritation to nasal mucosa limited its application. In this regard, deoxycholate-chitosan-hydroxybutyl nanoparticles with CTZ covalently grafted and free CTZ encapsulated (CTZ:CDHBCs-NPs) were synthesized as nasal adaptive nano-drug delivery systems. CDHBCs-NPs with various lower critical solution temperature (LCST) (29, 33, 37 °C) were prepared, with particle sizes of ~120 nm and zeta potentials of ~4 mV. In nasal condition (pH 5.5, 33 °C), the diameters of CDHBCs-NPs increased slightly (~129 nm to ~134 nm) because of the pH-responsive expansion. Burst release of free CTZ from CDHBC-29-NPs (~76%) was significantly (p < 0.05) accelerated compared with that of CDHBC-33-NPs and CDHBC-37-NPs (~60%), owing to thermo sensitive drug squeeze out (T > LCST). Incubating with lysozyme (30 µg/mL), CDHBCs-NPs swelled and exhibited ~2-fold increase (p < 0.01) of sizes, with additional CTZ releasing (~5%) attributing to the digestion of polysaccharide backbone covalent connected with CTZ. It could be speculated that stimuli-responsive CDHBCs-NPs might hold tremendous potential as nasal adaptive delivery vehicles in allergic airway inflammatory diseases therapy.


Assuntos
Antialérgicos/administração & dosagem , Quitosana/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Mucosa Nasal/efeitos dos fármacos , Composição de Medicamentos , Liberação Controlada de Fármacos , Cinética , Estrutura Molecular , Tamanho da Partícula , Espectroscopia de Prótons por Ressonância Magnética , Temperatura Ambiente
20.
Int J Biol Macromol ; 132: 1090-1097, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30902715

RESUMO

We have designed microcapsules-immobilized composite capsules and evaluated the oral delivery efficacy. The composite capsules were developed by encapsulating Perinereis aibuhitensis extract (PaE), a model substance possessing antioxidant activity, loaded gum Arabic/gelatin microcapsules in calcium alginate (CA) hydrogel (PaE:CA/GA/GE-CCs). In vitro antioxidant assay showed the obtained composite capsules were able to protect PaE from gastric acid, since O2- scavenging rate of encapsulated PaE was about 1.8 folds as that of free PaE after 5 h incubation in simulated gastrointestinal fluid. Moreover, in vivo study showed that after the treatment of oral administration for 30 days, the mice of PaE:CA/GA/GE-CCs group suffered significantly lower oxidative stress level than those of other groups, illustrated as higher SOD and catalase activity, as well as lower malondialdehyde content in liver cells. The results demonstrated the composite capsules could concentrate PaE in small intestine, and enhance the absorption efficiency and in vivo efficacy.


Assuntos
Alginatos/química , Antioxidantes/administração & dosagem , Antioxidantes/química , Portadores de Fármacos/química , Gelatina/química , Goma Arábica/química , Hidrogéis/química , Administração Oral , Animais , Antioxidantes/farmacologia , Cápsulas , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/toxicidade , Teste de Materiais , Camundongos , Estresse Oxidativo/efeitos dos fármacos
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