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1.
J Control Release ; 368: 219-232, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367862

RESUMO

Dual pathological barriers, including capillarized liver sinusoidal endothelial cells (LSECs) and deposited extracellular matrix (ECM), result in insufficient drug delivery, significantly compromising the anti-fibrosis efficacy. Additionally, excessive reactive oxygen species (ROS) in the hepatic microenvironment are crucial factors contributing to the progression of liver fibrosis. Hence, hyaluronic acid (HA) modified liposomes co-delivering all-trans retinoic acid (RA) and L-arginine (L-arg) were constructed to reverse hepatic fibrosis. By exhibiting exceptional responsiveness to the fibrotic microenvironment, our cleverly constructed liposomes efficiently disrupted the hepatic sinus pathological barrier, leading to enhanced accumulation of liposomes in activated hepatic stellate cells (HSCs) and subsequent induction of HSCs quiescence. Specially, excessive ROS in liver fibrosis promotes the conversion of loaded L-arg to nitric oxide (NO). The ensuing NO serves to reestablish the fenestrae structure of capillarized LSECs, thereby augmenting the likelihood of liposomes reaching the hepatic sinus space. Furthermore, subsequent oxidation of NO by ROS into peroxynitrite activates pro-matrix metalloproteinases into matrix metalloproteinases, which further disrupts the deposited ECM barrier. Consequently, this NO-induced cascade process greatly amplifies the accumulation of liposomes within activated HSCs. More importantly, the released RA could induce quiescence of activated HSCs by significantly downregulating the expression of myosin light chain-2, thereby effectively mitigating excessive collagen synthesis and ultimately leading to the reversal of liver fibrosis. Overall, this integrated systemic strategy has taken a significant step forward in advancing the treatment of liver fibrosis.


Assuntos
Células Estreladas do Fígado , Lipossomos , Humanos , Lipossomos/metabolismo , Células Estreladas do Fígado/metabolismo , Células Endoteliais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cirrose Hepática/metabolismo , Fígado/metabolismo , Metaloproteinases da Matriz/metabolismo
2.
Thorac Cancer ; 15(9): 693-701, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316629

RESUMO

BACKGROUND: Cancer-related pain is one of the common priority symptoms in advanced lung cancer patients at the end-of-life (EOL). Alleviating pain is undoubtedly a critical component of palliative care in lung cancer. Our study was initiated to examined trends in opioid prescription-level outcomes as potential indicators of undertreated pain in China. METHODS: This study used data on 1330 patients diagnosed with lung cancer of urban city medical insurance in China who died between 2014 and 2017. Opioid prescription-level outcomes were determined by annual trends of the proportion of patients filling an opioid prescription, the total dose of opioids filled by decedents, and morphine milligram equivalents per day (MMED) at the EOL (defined as the 60 days before death). We further analyzed monthly changes in the number of opioid prescriptions filled, MMED, and mean daily dose of opioids per prescription (MDDP) of the last 60 days of life by year at death and age, respectively. RESULTS: A total of 959 patients with exact dates of death were included, with 432 cases (45.06%; 95% CI: 44.36%-45.77%) receiving at least one opioid prescription at the EOL. The declining trends were shown in the proportion of patients filling any opioid prescription, the total dose of opioids filled by decedents and MMED, with an annual decrease of 0.341% (p = 0.01), 104.23 mg (p = 0.011) and 2.84 mg (p = 0.014), respectively. Within the 31-60 days to the 0-30 days of life, the MMED declined 6.08 mg (95% CI: -7.14 to -5.03; p = 0.000351), while the number of opioid prescriptions rose 0.66 (95% CI: 0.160-1.16; p = 0.025). Like the MMED, the MDDP fell 4.11 mg (95% CI: -5.86 to -2.37; p = 0.005) within the last month before death compared to the previous month. CONCLUSION: Terminal lung cancer populations in urban China have experienced reduced access to opioids at the EOL. The clinicians did not prescribe a satisfactory dose of opioids per prescription, while the patients suffered increasing pain in the last 30 days of life. Sufficient opioid analgesic administration should be advocated for lung cancer patients during the EOL period.


Assuntos
Seguro , Neoplasias Pulmonares , Humanos , Analgésicos Opioides/uso terapêutico , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/tratamento farmacológico , Subtratamento , Dor/tratamento farmacológico , Morfina
3.
Int J Pharm ; 642: 123167, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37356511

RESUMO

Liver fibrosis (LF) is one of the major diseases that threaten human health. Until now, no effective drugs have been approved for clinical anti-liver fibrosis treatment. In this study, zeolitic imidazolate framework-8 (ZIF-8) lipid nanoparticles loaded with pirfenidone (PFD) and modified with vitamin A (VA) were constructed (VA-PFD@ZIF-8@DMPC NPs). PFD was embedded in ZIF-8 by the "one-pot" method, and the prepared ZIF-8 had a small particle size (84.3 nm) and high drug loading (54.46%). Moreover, the inherent pH sensitivity of ZIF-8 makes it stable in a normal physiological environment and collapsed in an acidic environment, thus controlling drug release and preventing drug leakage. Besides, the phospholipid layer makes the nano-drug delivery system dispersible and improves its biocompatibility. More importantly, VA is modified on the surface of nanoparticles (NPs), which can target the highly expressed retinol-binding protein receptor (RBPR) on the surface of hepatic stellate cells (HSCs), thereby accurately increasing the local drug concentration at the site of LF. In vivo experiments showed that VA-PFD@ZIF-8@DMPC NPs can reduce liver injury, improve the degree of LF, and exert specific therapeutic effects on LF. In conclusion, this nano-delivery system may become a novel and effective anti-liver fibrosis treatment.


Assuntos
Nanopartículas , Zeolitas , Humanos , Vitamina A/uso terapêutico , Dimiristoilfosfatidilcolina , Cirrose Hepática/tratamento farmacológico
4.
J Colloid Interface Sci ; 645: 607-617, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37167910

RESUMO

Synergistic therapies of photodynamic therapy (PDT) and chemodynamic therapy (CDT) via metal-organic frameworks (MOF) for cancer treatment have recently attracted a lot of attentions because of the limitations of insufficient reactive oxygen species (ROS) in single-modality approaches. However, few studies explored on the use of increased ROS synergized with chemotherapy (CT) to address the issue of inadequate anti-tumor efficacy in single-modality regimens. Here, the desired cascade nanoplatforms (noted as MOF(Cu)@Dox-PL NPs) were fabricated by a solvothermal method using tetrakis (4-carboxyphenyl) porphyrin (TCPP) and zirconyl(di)chloride octahydrate (ZrOCl2·8H2O) as raw material, followed by Cu2+ introduced into the porphyrin ring and doxorubicin (DOX) loaded into the nanoframework. In addition, the nanoparticles (NPs) were electrostatically and hydrophobically coated with phospholipid (PL) to improve the biocompatibility of the nanosystems. Singlet oxygen (1O2) was created by the MOF(Cu)@Dox-PL NPs to disturb intracellular redox equilibrium. The acidic microenvironment in cancer cells may cause the prior release of DOX, which encourages the production of hydrogen peroxide (H2O2). And the doped Cu2+ could deplete overexpressed reduced glutathione (GSH) to produce hydroxyl radicals (·OH) by catalyzing H2O2, further causing redox dyshomeostasis. In vivo experiments revealed that MOF(Cu)@Dox-PL nanosystem possessed good biosafety and a compelling therapeutic effect in 4T1 tumor-bearing mice. As a novel nanosystem, MOF(Cu)@Dox-PL NPs showed great potential in synergistic therapy based on redox dyshomeostasis for improving anti-tumor efficacy with high specificity.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Porfirinas , Animais , Camundongos , Estruturas Metalorgânicas/farmacologia , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias/tratamento farmacológico , Oxirredução , Homeostase , Porfirinas/farmacologia , Linhagem Celular Tumoral , Glutationa/metabolismo , Microambiente Tumoral
5.
ACS Appl Mater Interfaces ; 15(14): 18191-18204, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36975190

RESUMO

Chemodynamic therapy (CDT) is an emerging tumor treatment; however, it is hindered by insufficient endogenous hydrogen peroxide (H2O2) and high glutathione (GSH) concentrations in the tumor microenvironment (TME). Furthermore, CDT has limited therapeutic efficacy as a monotherapy. To overcome these limitations, in this study, a nanoplatform is designed and constructed from Cu-doped mesoporous Prussian blue (CMPB)-encapsulated glucose oxidase (GOx) with a coating of hyaluronic acid (HA) modified with a nitric oxide donor (HN). In the proposed GOx@CMPB-HN nanoparticles, the dopant Cu2+ ions are crucial to combining and mutually promoting multiple therapeutic approaches, namely, CDT, photothermal therapy (PTT), and starvation therapy. The dopant Cu2+ ions in CMPB protect against reactive oxygen species to deplete the intracellular GSH in the TME. Additionally, the byproduct Cu+ ions act as a substrate for a Fenton-like reaction that activates CDT. Moreover, H2O2, which is another important substrate, is produced in large quantities through intracellular glucose depletion caused by the nanoparticle-loaded GOx, and the gluconic acid produced in this reaction further enhances the TME acidity and creates a better catalytic environment for CDT. In addition, Cu2+ doping greatly improves the mesoporous Prussian blue (MPB) photothermal conversion performance, and the resultant increase in temperature accelerates CDT catalysis. Finally, the HN coating enables the nanoparticles to actively target CD44 receptors in cancer cells and also enhances vascular permeability. Therefore, this coating has multiple effects, such as facilitating enhanced permeability and retention and deep laser penetration. In vitro and in vivo experiments demonstrate that the proposed GOx@CMPB-HN nanoplatform significantly inhibits tumor growth with the help of in situ enhanced synergistic therapies based on the properties of the TME. The developed nanoplatform has the potential to be applied to cancer treatment and introduces new avenues for tumor treatment research.


Assuntos
Nanopartículas , Neoplasias , Humanos , Peróxido de Hidrogênio , Terapia Fototérmica , Catálise , Ferrocianetos/farmacologia , Glucose Oxidase , Glutationa , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral
6.
Front Pharmacol ; 13: 867477, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784758

RESUMO

Succinum is an organic mineral formed from the resin of ancient coniferous and leguminous plants, which is applied for tranquilizing mood, promoting blood circulation, and removing blood stasis in Chinese medicine. For quite a long time, the modern research of succinum mainly focuses on the study of physical and chemical properties and authenticity identification while few reports on its medicinal mechanism. In current study, we evaluated different solvent extracts of succinum on carotid artery ligation rats mimicking vascular dementia. It was found that ethyl acetate extracts of succinum significantly improved the learning and memory abilities of model rats and inhibited neuronal apoptosis in the hippocampus. On a mice hippocampal neuronal cell line (HT22), ethyl acetate extracts of succinum also exerted better action trend in inhibiting cell apoptosis induced by oxygen glucose deprivation (OGD). By using XAV-939 on both in vivo and in vitro studies, it was found that ethyl acetate extracts of succinum might exert these functions by regulating the GSK3ß/ß-catenin pathway. These studies revealed the neuronal function of succinum, which explained the traditional effects of succinum and provided more modern scientific basis for its clinical application.

7.
Foods ; 11(2)2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35053911

RESUMO

High resistance to heating treatments is a prerequisite for ready-to-eat (RTE) surimi products. In this study, emulsion-formulated surimi gels were prepared, and the effects of oil types and emulsification degrees on the thermal stability of surimi gel were investigated. The results showed the gel properties of surimi gels were modulated by oil types and emulsification degrees. In detail, the rising pre-emulsification ratio caused the increase of the emulsifying activity index (EAI) and decrease of emulsifying stability index (ESI) for both emulsions. The larger droplet sizes of perilla seed oil than soybean oil may be responsible for their emulsifying stability difference. The gel strength, water retention, dynamic modulus and texture properties of both kinds of surimi gels displayed a firstly increased and then decreased tendency with the rising pre-emulsification ratios. The peak values were obtained as perilla seed oil emulsion with emulsification ratio of 20% group (P1) and soybean oil emulsion with emulsification ratio of 40% group (S2), respectively. Anyway, all emulsion gels showed higher thermal stability than the control group regardless of oil types. Similar curves were also obtained for the changes of hydrogen bond, ionic bond and hydrophobic interactions. Overall, perilla seed oil emulsion with emulsification ratio of 20% (P1 group) contributed to the improved thermal stability of surimi gels.

8.
Phytother Res ; 35(5): 2665-2677, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33438327

RESUMO

Dendrobium officinale flos (DOF) is the flower of Dendrobium officinale Kimura et Migo, which is usually regarded as a by-product of Dendrobii Offcinalis Caulis. Based on its use as an alternative medicine, we evaluated the antidepressant-like effect of DOF extracts on chronic, unpredictable, mild stress-induced, depression-like behaviour in mice and tested the effects of DOF on the regulation of neurotrophic factors in mouse astrocyte primary cultures and PC12 cell lines. Oral treatment with DOF ethanol extract (DOF-E) could alleviate depression-like behaviours in stress-exposed mice, as evidenced by increased sucrose consumption and decreased immobile time in a forced swim test. In the hippocampus, DOF extracts increased the expression of NGF and BDNF, both at the transcriptional and protein levels. In astrocytes, DOF-E increased the expression of NGF and BDNF via a cAMP-dependent mechanism and regulated plasminogen and matrix metallopeptidase 9 (MMP-9), which are related to the metabolic regulation of neurotrophic factors. In PC12 cells, DOF-E induced the expression of neurofilaments and potentiated the induction of neurite outgrowth upon treatment with a low dose of NGF. Based on these findings, DOF might be used as a supplement for antidepressant therapy in patients with depression.

9.
PLoS One ; 15(6): e0233571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497134

RESUMO

PURPOSE: This meta-analysis aimed to assess the efficacy and safety of cyclin-dependent kinase (CDK) 4/6 inhibitors plus endocrine therapy (ET) in hormonal receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC). METHODS: We searched PubMed, Embase, Cochrane, ClinicalTrials.gov., ASCO, ESMO and AACR databases from inception to October 10, 2019 for randomized controlled trials (RCTs) that compared CDK 4/6 inhibitors plus ET to single-agent ET with no treatment-line restriction. The main outcomes analyzed were progression-free survival (PFS), overall survival (OS), objective response rate (ORR), clinical benefit rate (CBR), and adverse events (AEs). RESULTS: Of 938 identified studies, 9 RCTs with 5043 women were eligible and included. Compared with ET alone, CDK 4/6 inhibitors and ET combination improved in PFS (hazard ratio (HR) 0.54, 95% confidence interval (CI) 0.50-0.59, p< 0.00001) and OS (HR 0.77, 95% CI 0.69-0.85, p< 0.00001), regardless of ET strategies (HR 0.54, 95% CI 0.50-0.59 in PFS; HR 0.77, 95% CI 0.69-0.85 in OS), treatment line of advanced disease (HR 0.52, 95% CI 0.46-0.59 in PFS; HR 0.75, 95% CI 0.66-0.85 in OS) and menopausal status (HR 0.54, 95% CI 0.50-0.58 in PFS; HR 0.76, 95% CI 0.68-0.84 in OS). Higher risk of grade 3/4 AEs (RR 2.66, 95% CI 2.44-2.90, p < 0.00001) were observed in the combination group than in the ET group. CONCLUSIONS: Combination therapy with CDK 4/6 inhibitors and ET prolongs survival in HR+/ HER2- ABC. This combination is a better therapeutic strategy than endocrine monotherapy in HR+/HER2- ABC, regardless of treatment line, menopausal status and other individual characteristics.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/efeitos adversos
10.
J Ethnopharmacol ; 261: 113055, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32592887

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Kai-Xin-San (KXS) has been prescribed by TCM doctors for treating psychiatric diseases with the core symptoms of anhedonia, amnesia, and dizziness. According to the symptoms of patients, KXS series formulae are created by varying the compatible ratio of herbs. Today, these formulae are still used in the clinic to treat major depressive disorders. AIM OF THE STUDY: We hoped to evaluate the antidepressant-like effect of Kai-Xin-San via regulation of the gut-brain axis. MATERIALS AND METHODS: Standardized extracts of three representative compatible ratios of KXS had been prepared, and quality control of the extracts was performed by HPLC-MS/MS. Chronic unpredictable mild stress (CUMS)-induced depression-like mice were used as the depression animal model. After KXS treatment, the antidepressant-like effects of KXS were assessed by behavioural tests. The gut microbiota compositions in the faeces were determined by 16S rRNA sequencing technology. The levels of LPS, pro-inflammatory cytokines and HPA-axis-related hormones were measured by ELISA kits, and the expression of barrier proteins in the small intestines and prefrontal cortex were determined by Western blot analysis. Furthermore, antibiotics were used to determine the correlation between KXS exerting an antidepressant-like effect and regulating the gut-brain axis. RESULTS: KXS alleviated depression-like behaviours in CUMS-exposed mice. Furthermore, these parameters were also found to be changed after KXS treatment. Alteration of the gut microbiota composition were found in the small intestines. A decrease in the LPS and the pro-inflammatory cytokines were found in both the small intestine and brain. An increase in the tight junction proteins was found in the gut epithelium barrier and the blood-brain barrier. A decrease in the stress-related hormones was found in the central nervous system. Furthermore, antibiotic treatment attenuated the antidepressant-like effect of KXS in CUMS-exposed mice. CONCLUSIONS: KXS exerted an antidepressant-like effect regulating the gut-brain axis, which included gut micro-environment modification, suppression of neuronal inflammation in the brain and inhibition of HPA axis activation in CUMS-induced depression-like mice.


Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Citocinas/metabolismo , Depressão/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Intestino Delgado/microbiologia , Estresse Psicológico/tratamento farmacológico , Animais , Encéfalo/metabolismo , Doença Crônica , Depressão/metabolismo , Depressão/microbiologia , Depressão/psicologia , Modelos Animais de Doenças , Disbiose , Fluoxetina/farmacologia , Interações Hospedeiro-Patógeno , Intestino Delgado/metabolismo , Masculino , Camundongos Endogâmicos ICR , Estresse Psicológico/metabolismo , Estresse Psicológico/microbiologia , Estresse Psicológico/psicologia
11.
Pathol Res Pract ; 215(11): 152597, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31564566

RESUMO

Evidence suggests that DNA repair capacity manifested by intact functional base excision repair and mismatch repair (MMR) pathways is related to the prognosis of multiple cancer types. Aldolase B (ALDOB) is well known for its role in metabolism and glycolysis. The expression of ALDOB in colon adenocarcinoma and the relationship between its expression and colon adenocarcinoma prognosis remain controversial; in addition, the potential role of ALDOB in DNA MMR has not yet been reported. In this study, we identified a cluster of DNA repair-related proteins that interact with ALDOB in the colon adenocarcinoma cell line HCT116. Expression analysis of colon adenocarcinoma data from the Cancer Genome Atlas (TCGA-COAD data, n = 551) indicated that ALDOB mRNA expression was significantly higher in specimens with microsatellite instability (MSI) than in specimens with microsatellite stability (MSS). Regarding prognosis, colon adenocarcinoma patients with high ALDOB mRNA expression had longer overall survival (OS). Higher expression of ALDOB protein was significantly correlated with MMR deficiency (d-MMR) in formalin-fixed paraffin-embedded (FFPE) patient specimens. The expression of ALDOB was significantly elevated in colon adenocarcinoma cell lines. Further evidence indicated that rather than affecting proliferation, ALDOB overexpression induced the functional loss of MMR proteins and in turn caused irreversible DNA damage via disrupting EZH2-Rad51 expression and then caused apoptosis by ERK inactivation. Overall, our study demonstrates that high ALDOB expression impairs DNA MMR and induces apoptosis in colon adenocarcinoma. ALDOB may be a new biomarker associated with d-MMR and an independent prognostic factor for colon adenocarcinoma.


Assuntos
Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Reparo de Erro de Pareamento de DNA/fisiologia , Frutose-Bifosfato Aldolase/metabolismo , Apoptose/fisiologia , Humanos , Instabilidade de Microssatélites
12.
Drug Deliv ; 26(1): 708-716, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31290708

RESUMO

In this study, a synthetic high-density lipoprotein (sHDL), peptide-based nanocarrier loaded with docetaxel (DTX) was constructed, against breast cancer. The thermodynamic and molecular dynamic analyses were conducted to examine the stability of nanoparticles synthesized from mimetic peptide 5 A and various types of phospholipids. Furthermore, the cellular uptake and in vivo fluorescence imaging analysis experiments, with scavenger receptor B-I (SR-BI) were carried out to examine the tumor-targeting ability of sHDL. The nanoparticles were investigated for their pharmacodynamic and cytotoxic effects to show their effectivity as anti-tumor agents. The results showed that the synthesized sHDL nanoparticles exhibited a high payload of DTX, sustained drug release properties, and excellent biocompatibility. Moreover, DTX-sHDL nanoparticles enhanced the uptake of DTX, increased the cytotoxicity against MCF-7 cells, and reduced the off-target side-effects to normal cells. Finally, experiments in 4T1 cell line-bearing mice indicate that inhibition of tumor growth by DTX-sHDL nanoparticles was superior to that of free DTX group. Thus, the sHDL nanoparticles are a promising drug delivery vehicle for improving the efficacy of anti-cancer drugs.


Assuntos
Antineoplásicos/administração & dosagem , Apolipoproteína A-I/química , Docetaxel/administração & dosagem , Portadores de Fármacos/química , Neoplasias Mamárias Experimentais/tratamento farmacológico , Nanopartículas/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Materiais Biomiméticos , Preparações de Ação Retardada , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Docetaxel/toxicidade , Células Epiteliais , Feminino , Humanos , Células MCF-7 , Camundongos , Nanopartículas/toxicidade , Imagem Óptica , Peptídeos/química , Receptores Depuradores Classe B/metabolismo
13.
Langmuir ; 28(37): 13261-73, 2012 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-22921144

RESUMO

Alginate/chitosan/alginate (ACA) hydrogel microcapsules were modified with methoxy poly(ethylene glycol) (MPEG) to improve protein repellency and biocompatibility. Increased MPEG surface graft density (n(S)) on hydrogel microcapsules was achieved by controlling the grafting parameters including the buffer layer substrate, membrane thickness, and grafting method. X-ray photoelectron spectroscopy (XPS) model was employed to quantitatively analyze n(S) on this three-dimensional (3D) hydrogel network structure. Our results indicated that neutralizing with alginate, increasing membrane thickness, and in situ covalent grafting could increase n(S) effectively. ACAC(PEG) was more promising than ACC(PEG) in protein repellency because alginate supplied more -COO(-) negative binding sites and prevented MPEG from diffusing. The n(S) increased with membrane thickness, showing better protein repellency. Moreover, the in situ covalent grafting provided an effective way to enhance n(S), and 1.00 ± 0.03 chains/nm(2) was achieved, exhibiting almost complete immunity to protein adsorption. This antifouling hydrogel biomaterial is expected to be useful in transplantation in vivo.


Assuntos
Alginatos/química , Quitosana/química , Fibrinogênio/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Imunoglobulina G/química , Polietilenoglicóis/química , Adsorção , Cápsulas , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Propriedades de Superfície
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