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1.
Gels ; 9(9)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37754389

RESUMEN

A simple and cost-effective method for the fabrication of a safe, dual-responsive, highly stretchable, self-healing and injectable hydrogel is reported based on a combination of dynamic boronate ester bonds and hydrogen bonding interactions. The mechanical properties of the hydrogel are tunable by adjusting the molar ratios between sugar moieties on the polymer and borax. It was remarkable to note that the 2:1 ratio of sugar and borate ion significantly improves the mechanical strength of the hydrogel. The injectability, self-healing and stretchability properties of the hydrogel were also examined. In addition, the impact of the variation of the pH and the addition of free sugar responsiveness of the hydrogel was studied. High MRC-5 cell viability was noticed by the 3D live/dead assay after 24 h cell culture within the hydrogel scaffold. Hence, the developed hydrogels have desirable features that warrant their applications for drug delivery, scaffolds for cell and tissue engineering.

2.
J Mater Chem B ; 11(30): 7228-7238, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37431576

RESUMEN

Antimicrobial hydrogel dressings have received extensive attention for their wide and promising applications in preventing infections associated with wound healing. However, the development of versatile antibacterial hydrogels inevitably leads to complex structures, which restricts their applications. In this work, a multifunctional antibacterial hydrogel based on a reversible diolborate bond crosslinked network was prepared via the interactions between the zwitterionic glycopolymer poly[(2-methacryloyloxyethyl phosphorylcholine)-co-(N,N-dimethylacrylamide)-co-(2-lactobionamidoethyl methacrylamide)] (PMDL) and borax in conjunction with a simple mixing of Ag NPs within 10 s. The obtained PMDL-12%/borax/Ag NP hydrogel displays a rapid self-healing ability and excellent injectability, as well as good adhesiveness to biological tissues and surfaces of various materials. Moreover, the hydrogels exhibit efficient antibacterial activities against Escherichia coli and Staphylococcus aureus, which could prevent bacterial infections in wound care. The multifunctional hydrogel also shows good cytocompatibility and hemocompatibility. Importantly, in vivo wound healing evaluation of a mouse full-thickness skin defect model confirms that the hydrogel effectively accelerates cutaneous regeneration and wound healing by regulating inflammation and promoting collagen deposition. This multifunctional wound dressing hydrogel prepared using a facile strategy has promising application in biomedical areas.


Asunto(s)
Antibacterianos , Hidrogeles , Animales , Ratones , Hidrogeles/farmacología , Antibacterianos/farmacología , Piel , Vendajes , Modelos Animales de Enfermedad , Escherichia coli
3.
Mol Pharm ; 20(6): 3100-3114, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37148327

RESUMEN

Solid tumors are often poorly vascularized, which impairs oxygen supply and drug delivery to the cells. This often leads to genetic and translational adaptations that promote tumor progression, invasion, metastasis, and resistance to conventional chemo-/radiotherapy and immunotherapy. A hypoxia-directed nanosensitizer formulation of a hypoxia-activated prodrug (HAP) was developed by encapsulating iodoazomycin arabinofuranoside (IAZA), a 2-nitroimidazole nucleoside-based HAP, in a functionally modified carbohydrate-based nanogel, facilitating delivery and accrual selectively in the hypoxic head and neck and prostate cancer cells. Although IAZA has been reported as a clinically validated hypoxia diagnostic agent, recent studies have pointed to its promising hypoxia-selective anti-tumor properties, which make IAZA an excellent candidate for further exploration as a multimodal theranostic of hypoxic tumors. The nanogels are composed of a galactose-based shell with an inner core of thermoresponsive (di(ethylene glycol) methyl ethyl methacrylate) (DEGMA). Optimization of the nanogels led to high IAZA-loading capacity (≅80-88%) and a slow time-controlled release over 50 h. Furthermore, nanoIAZA (encapsulated IAZA) displayed superior in vitro hypoxia-selective cytotoxicity and radiosensitization in comparison to free IAZA in the head and neck (FaDu) and prostate (PC3) cancer cell lines. The acute systemic toxicity profile of the nanogel (NG1) was studied in immunocompromised mice, indicating no signs of toxicity. Additionally, growth inhibition of subcutaneous FaDu xenograft tumors was observed with nanoIAZA, demonstrating that this nanoformulation offers a significant improvement in tumor regression and overall survival compared to the control.


Asunto(s)
Hipoxia , Neoplasias de la Próstata , Masculino , Humanos , Ratones , Animales , Nanogeles , Hipoxia de la Célula , Neoplasias de la Próstata/tratamiento farmacológico , Galactosa , Línea Celular Tumoral
4.
Biomater Sci ; 11(1): 128-139, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36377684

RESUMEN

Infections caused by biofouling have become a serious concern in the health care sector. Multifunctional coatings with antifouling and antibacterial properties are widely used to combat these biofouling related infections. However, in practice macro or micro scratches or damages can happen to the coating, which can act as an active site for microbial deposition and destroy the antifouling or antibacterial functionality of the coating. Considering this fact, we have developed an excellent biocompatible and multifunctional coating with antifouling, antibacterial and self-healing properties. In this study, prebiotic chemistry inspired self-polymerization of aminomalononitrile (AMN) was used as a primary coating layer, which acted as a primer to graft vitamin B5 analogous methacrylamide polymer poly(B5AMA) and zwitterionic compound 2-methacryloyloxyethyl phosphorylcholine (MPC) containing polymer poly (MPC-st-B5AMA) by forming strong hydrogen bonds. B5AMA having multiple polar groups in the structure acted as an intrinsic self-healing material and showed an excellent antifouling property against protein and bacteria, maintaining a good hydration layer similar to the MPC containing polymer. To impart the antibacterial property to the coating, silver nanoparticles have also been incorporated, which showed more than 90% killing efficiency against both Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria with significant reduction of their adhesion on the surface. Incorporation of self-healing property into the fouling repelling and antibacterial coating can significantly extend the durability of the multifunctional coating, making it promising for biomedical applications.


Asunto(s)
Incrustaciones Biológicas , Nanopartículas del Metal , Polímeros/farmacología , Incrustaciones Biológicas/prevención & control , Staphylococcus aureus , Escherichia coli , Plata , Antibacterianos/farmacología , Antibacterianos/química , Propiedades de Superficie , Materiales Biocompatibles Revestidos/farmacología , Materiales Biocompatibles Revestidos/química
5.
ACS Macro Lett ; 11(4): 580-587, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35575337

RESUMEN

Overexpression of epidermal growth factor receptor (EGFR) is observed in multiple cancers such as colorectal, lung, and cervical solid tumors. Regulating the EGFR expression is an efficient strategy to manage these malignancies, and it can be achieved by using short interfering RNA (siRNA). Cell-penetrating peptides (CPPs) demonstrated an excellent capability to enhance the cellular uptake of siRNA, but high knockdown efficiencies have not been achieved due to endosomal entrapment. In this work, Schiff's base reaction was used to modify a block {P[LAEMA(2-lactobionamidoethyl methacrylamide)37]-b-P[FPMA(4-formyl phenyl methacrylate)2-st-DMA(N,N-dimethylacrylamide)2], P2} and two statistical [P(LAEMA23-st-FPMA3) (P3) and P(LAEMA25-st-FPMA2-st-DMA2) (P4)] aldehyde-based and galactose-based polymers, prepared via reversible addition-fragmentation chain-transfer (RAFT) polymerization. An arginine-rich peptide (ARP, KRRKRRRRRK) was used as a cell-penetrating peptide (CPP) and conjugated to the polymers via a Schiff base reaction. The resulting glycopolymer-peptide conjugates were utilized to condense the siRNA to prepare polyplexes with multivalent CPPs (MCPPs, a nanoparticle with multiple copies of the CPP) to enhance the endosomal escape. The polyplexes have different surface properties as determined by the architecture of polymers and the insertion of dimethyl amide moieties. The enhancement of cellular internalization of ARP was observed by labeling the polyplexes with fluorescein isothiocyanate (FITC)-siRNA showing a localization of polyplexes in the cytoplasm of a HeLa (cervical cancer) cell line. In the in vitro EFGR silencing study, the statistical glycopolymer-peptide (P3-P) polyplexes had superior EGFR silencing efficiency in comparison with the other polymers that were studied. Furthermore, P3-P polyplexes led to less off-targeting silencing than lipofectamine 3000. These encouraging results confirmed the potency of decorating galactose-based polymers with CPP, like ARP for their application in siRNA delivery and management of cervical carcinomas.


Asunto(s)
Péptidos de Penetración Celular , Humanos , Receptores ErbB/genética , Galactosa , Polímeros/química , ARN Interferente Pequeño/genética
6.
Biomacromolecules ; 23(6): 2552-2561, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35608162

RESUMEN

Injectable and self-healing hydrogels with exemplary biocompatibility and tunable mechanical properties are urgently needed due to their significant advantages for tissue engineering applications. Here, we report a new temperature-responsive aldehyde hydrogel with dual physical-cross-linked networks and injectable and self-healing properties prepared from an ABA-type triblock copolymer, poly{[FPMA(4-formylphenyl methacrylate)-co-DEGMA[di(ethylene glycol) methyl ether methacrylate]-b-MPC(2-methacryloyloxyethyl phosphorylcholine)-b-(FPMA-co-DEGMA)}. The thermoresponsive poly(DEGMA) segments drive the dehydration and hydrophobic interaction, enabling polymer chain winding as the first cross-linking network, when the temperature is raised above the critical gelation temperature. Meanwhile, the benzaldehyde groups offer physical interactions, including hydrogen bonding and hydrophobic and π-π stacking interactions as the second cross-linking network. When increasing the benzaldehyde content in the triblock copolymers from 0 to 8.2 mol %, the critical gelation temperature of the resulted hydrogels dropped from 35.5 to 19.9 °C and the mechanical modulus increased from 21 to 1411 Pa. Owing to the physical-cross-linked networks, the hydrogel demonstrated excellent injectability and self-healing properties. The cell viabilities tested from MTT assays toward both normal lung fibroblast cells (MRC-5) and cancerous cervical (HeLa) cells were found to be 100 and 101%, respectively, for varying polymer concentrations up to 1 mg/mL. The 3D cell encapsulation of the hydrogels was evaluated by a cytotoxicity Live/Dead assay, showing 92% cell viability. With these attractive physiochemical and biological properties, this temperature-responsive aldehyde hydrogel can be a promising candidate as a cell scaffold for tissue engineering.


Asunto(s)
Benzaldehídos , Hidrogeles , Aldehídos , Hidrogeles/química , Hidrogeles/farmacología , Metacrilatos/química , Polímeros/química , Temperatura
7.
Biomater Sci ; 10(7): 1787-1794, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35225301

RESUMEN

Preparation of antibacterial coating materials is considered an effective strategy to prevent medical device-related infections. In the present study, by combining 2-lactobionamidoethyl methacrylamide with a uniquely structured borneol compound, new copolymers poly(2-lactobionamidoethyl methacrylamide-co-glycidyl methacrylate-co-isobornyl acrylate) (poly(LAEMA-co-GMA-co-BA)) were synthesized by a simple free-radical polymerization. An amine containing silane layer was first prepared on the substrate surface by a silanization reaction. The glycopolymers were grafted onto the silane layer through covalent bonding to obtain glycosylated coatings. X-ray photoelectron spectroscopy (XPS) confirmed the successful preparation of the APTES-functionalized surface and polymer layers. The surface wettability was measured by the contact angle (CA). The coated surfaces were relatively flat and smooth as confirmed by Atomic Force Microscopy (AFM). Moreover, the prepared coatings showed good antibacterial adhesion properties toward both E. coli and S. aureus. Furthermore, no significant cytotoxicity to the MRC-5 cells (lung fibroblasts) in vitro was observed, indicating the good biocompatibility of the antibacterial coatings. This study provides an excellent strategy for designing an antibacterial surface containing glycopolymers and natural antibacterial compounds, and these coatings may be suitable for medical devices.


Asunto(s)
Escherichia coli , Staphylococcus aureus , Antibacterianos/química , Antibacterianos/farmacología , Canfanos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Propiedades de Superficie
8.
ACS Appl Mater Interfaces ; 14(7): 9557-9569, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35144379

RESUMEN

The rapid accumulation of dead bacteria or protein on a bactericidal surface can reduce the effectiveness of the modified surface and alter its biocidal activity by shielding the surface biocide functional groups, promoting microbial attachment and subsequent biofilm formation. Thus, the alteration of biocidal activity due to biofilm formation can cause serious trouble including severe infection or implant or medical device failure leading to death. Therefore, developing a smart self-cleaning surface is of great interest. Ideally, such a surface can not only kill the attached microbials but also release the dead cells and foulants from the surface under a particular incitement on demand. In this project, a sugar-responsive self-cleaning coating has been developed by forming covalent boronic ester bonds between catechol groups from polydopamine and a benzoxaborole pendant from zwitterionic and cationic polymers. To incorporate antifouling properties and enhance the biocompatibility of the coating, bioinspired zwitterionic compound 2-methacryloyloxyethyl phosphorylcholine (MPC) was chosen and benzoxaborole pendant containing zwitterionic polymer poly(MPC-st-MAABO) (MAABO: 5-methacrylamido-1,2-benzoxaborole) was synthesized. Additionally to impart antibacterial properties to the surface, a quaternary ammonium containing cationic polymer poly(2-(methacryloyloxy)ethyl trimethylammonium (META)-st-MAABO)) was synthesized. These synthesized polymers were covalently grafted to a polydopamine (PDA) coated surface by forming a strong cyclic boronic ester complex with a catechol group of the PDA layer endowing the surface with bacteria contact-killing properties and capturing specific protein. After the addition of cis-diol containing competitive molecules, i.e., saccharides/sugars, this boronic ester complex with a catechol group of PDA was replaced and the attached polymer layer was cleaved from the surface, resulting in the release of both absorbed protein and live/killed bacteria electrostatically attached to the polymer layer. This dynamic self-cleaning surface can be a promising material for biomedical applications avoiding the gathering of dead cells and debris that are typically encountered on a traditional biocidal surface.


Asunto(s)
Incrustaciones Biológicas , Antibacterianos/química , Antibacterianos/farmacología , Bacterias , Incrustaciones Biológicas/prevención & control , Dopamina/farmacología , Fosforilcolina/química , Fosforilcolina/farmacología , Propiedades de Superficie
9.
Mol Pharm ; 19(6): 1766-1777, 2022 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-34473523

RESUMEN

Tirapazamine (TPZ) and its derivatives (TPZD) have shown their great potential for efficiently killing hypoxic cancer cells. However, unsatisfactory clinical outcomes resulting from the low bioavailability of the low-molecular TPZ and TPZD limited their further applications. Precise delivery and release of these prodrugs via functional nanocarriers can significantly improve the therapeutic effects due to the targeted drug delivery and enhanced permeability and retention (EPR) effect. Herein, zwitterionic block copolymer (BCP) micelles with aldehyde functional groups are prepared from the self-assembly of poly(2-methacryloyloxyethyl phosphorylcholine-b-poly(di(ethylene glycol) methyl ether methacrylate-co-4-formylphenyl methacrylate) [PMPC-b-P(DEGMA-co-FPMA)]. TPZD is then grafted onto PMPC-b-P(DEGMA-co-FPMA) to obtain a polymer-drug conjugate, PMPC-b-P(DEGMA-co-FPMA-g-TPZD) (BCP-TPZ), through the formation of a pH-responsive imine bond, exhibiting a pH-dependent drug release profile owing to the cleavage of the imine bond under acidic conditions. Outstandingly, BCP-TPZ shows around 13.7-fold higher cytotoxicity to hypoxic cancer cells in comparison to normoxic cancer cells evaluated through an in vitro cytotoxicity assay. The pH-responsiveness and hypoxia-specific cytotoxicity confer BCP-TPZ micelles a great potential to achieve precise delivery of TPZD and thus enhance the therapeutic effect toward tumor-hypoxia.


Asunto(s)
Micelas , Profármacos , Doxorrubicina/química , Humanos , Concentración de Iones de Hidrógeno , Hipoxia , Iminas , Metacrilatos/química , Polímeros/química , Profármacos/química , Profármacos/farmacología , Tirapazamina
11.
ACS Nano ; 15(6): 9913-9923, 2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-34037373

RESUMEN

Developing effective internal wound dressing materials is important for postoperative tissue regeneration while remains a challenge due to the poor biological environment-adaptability of conventional materials. Here, we report an example of injectable self-healing hydrogel based on gastric environment-adaptive supramolecular assembly, and have explored its application for gastric perforation healing. By leveraging the gastric environment-modulated supramolecular interactions, the self-assembled hydrogel network is orchestrated with sensitive thermo-responsibility, injectability, printability and rapid self-healing capability. The hydrogel dressing can effectively inhibit the attachment of microorganisms and demonstrates outstanding antibiofouling property. In vivo rat model further demonstrates the as-prepared hydrogel dressing simplifies the surgical procedures, reduces postoperative complications as well as enhances the healing process of gastric perforation compared with the conventional treatment. This work provides useful insights into the development of biological environment-adaptive functional materials for various biomedical applications.


Asunto(s)
Hidrogeles , Cicatrización de Heridas , Animales , Vendajes , Ratas
13.
Biomacromolecules ; 22(4): 1685-1694, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-33779160

RESUMEN

Injectable hydrogels have become a promising material for biomedical engineering applications, but microbial infection remains a common challenge in their application. In this study, we presented an injectable antibacterial hydrogel with self-healing property based on a dual cross-linking network structure of dynamic benzoxaborole-sugar and quadruple hydrogen bonds of the 2-ureido-4-pyrimidone (UPy) moieties at physiological pH. Dynamic rheological experiments demonstrated the gelatinous behavior of the double cross-linking network (storage modulus G' > loss modulus G″), and the modulus showed frequency-dependent behavior. The noncovalent interactions of UPy units in the polymer segment endowed the injectable hydrogels with good mechanical strength. By varying the solid contents, UPy units, as well as the pH, the mechanical properties of hydrogels could be controlled. Additionally, the hydrogels exhibited not only excellent self-healing and injectable properties but also pH and sugar dual-responsiveness. Moreover, the hydrogels could effectively inhibit the growth of both Escherichia coli and Staphylococcus aureus while exhibiting low toxicity. 3D cell encapsulation experiment results also demonstrated the potential use of these hydrogels as cell culture scaffolds. Taken together, the injectability, self-healing, and antimicrobial properties of the prepared hydrogels showed great promise for translational medicine, such as cell and tissue engineering applications.


Asunto(s)
Antibacterianos , Hidrogeles , Antibacterianos/farmacología , Gelatina , Staphylococcus aureus , Ingeniería de Tejidos
14.
ACS Appl Mater Interfaces ; 13(7): 9006-9014, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33576614

RESUMEN

The development and application of natural antibacterial materials have always been the focus of biomedical research. Borneol as a natural antibacterial compound has received extensive attention. However, the hydrophobicity caused by its unique structure limits its application range to a certain extent. In this study, we combine zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) with a complex bicyclic monoterpene structure borneol compound and prepare an excellent antifouling and antibacterial surface via the Schiff-base bond. The prepared coating has excellent hydrophilicity verified by the contact angle (CA), and its polymer layer is confirmed by X-ray photoelectron spectroscopy (XPS). The zwitterion MPC and borneol moieties in the copolymer play a coordinating role, relying on super hydration and the special stereochemical structure to prevent protein adsorption and inhibit bacterial adhesion, respectively, which are demonstrated by bovine serum albumin (BSA) adsorption and antibacterial activity test. Moreover, the water-soluble borneol derivative as the antibacterial surfaces we designed here was biocompatible toward MRC-5 (lung fibroblasts), as showed by in vitro cytotoxicity assays. Such results indicate the potential application of the as-prepared hydrophilic surfaces in the biomedical materials.


Asunto(s)
Antibacterianos/farmacología , Incrustaciones Biológicas/prevención & control , Canfanos/farmacología , Materiales Biocompatibles Revestidos/farmacología , Metacrilatos/farmacología , Fosforilcolina/análogos & derivados , Polímeros/farmacología , Adsorción , Antibacterianos/síntesis química , Antibacterianos/química , Canfanos/química , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/química , Escherichia coli/efectos de los fármacos , Humanos , Metacrilatos/química , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Tamaño de la Partícula , Fosforilcolina/química , Fosforilcolina/farmacología , Polímeros/síntesis química , Polímeros/química , Bases de Schiff/síntesis química , Bases de Schiff/química , Bases de Schiff/farmacología , Albúmina Sérica Bovina/química , Staphylococcus aureus/efectos de los fármacos , Propiedades de Superficie
15.
Biomacromolecules ; 22(2): 800-810, 2021 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-33320540

RESUMEN

Dual-cross-linked network (DCN) hydrogels with multiresponsive and self-healing properties are attracting intensive interests due to their enhanced mechanical strength for a wide range of applications. Herein, we developed a DCN hydrogel that combines a dynamic imine and a benzoxaboronic ester with a neutral pKa value (∼7.2) as dual linkages and contains biocompatible zwitterionic poly(2-methacryloyloxyethyl phosphorylcholine) [poly(MPC)] as the backbone. Oscillatory rheology result indicated shear strengthening mechanical properties compared to the single-cross-linked network (SCN) hydrogels, which use either imine bond or benzoxaboronic ester as the linkage alone. Due to the coexistence of stimuli-responsive imine and benzoxaboronic ester, the DCN hydrogels show sensitive multiple responsiveness to pH, sugar, and hydrogen peroxide. The dynamic nature of the dual linkages endows the DCN hydrogels with excellent self-healing ability after fracture. More importantly, the excellent biocompatibility and performance in three-dimensional (3D) cell encapsulation were established by a cytotoxicity Live/Dead assay, indicating DCN hydrogel's great potential as a cell culture scaffold. The biocompatible poly(MPC)-based backbone and the rapid formation of the cross-linking network make the DCN hydrogels promising candidates for future biomedical applications.


Asunto(s)
Ésteres , Hidrogeles , Reología
16.
Biomacromolecules ; 21(3): 1264-1273, 2020 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-31913606

RESUMEN

The capability to slow ice growth and recrystallization is compulsory in the cryopreservation of cells and tissues to avoid injuries associated with the physical and chemical responses of freezing and thawing. Cryoprotective agents (CPAs) have been used to restrain cryoinjury and improve cell survival, but some of these compounds pose greater risks for the clinical application of cryopreserved cells due to their inherent toxicity. Trehalose is known for its unique physicochemical properties and its interaction with the phospholipids of the plasma membrane, which can reduce cell osmotic stress and stabilized the cryopreserved cells. Nonetheless, there has been a shortage of relevant studies on the synthesis of trehalose-based CPAs. We hereby report the synthesis and evaluation of a trehalose-based polymer and hydrogel and its use as a cryoprotectant and three-dimensional (3D) cell scaffold for cell encapsulation and organoid production. In vitro cytotoxicity studies with the trehalose-based polymers (poly(Tre-ECH)) demonstrated biocompatibility up to 100 mg/mL. High post-thaw cell membrane integrity and post-thaw cell plating efficiencies were achieved after 24 h of incubation with skin fibroblast, HeLa (cervical), and PC3 (prostate) cancer cell lines under both controlled-rate and ultrarapid freezing protocols. Differential scanning calorimetry and a splat cooling assay for the determination of ice recrystallization inhibition activity corroborated the unique properties of these trehalose-based polyethers as cryoprotectants. Furthermore, the ability to form hydrogels as 3D cell scaffolds encourages the use of these novel polymers in the development of cell organoids and cryopreservation platforms.


Asunto(s)
Criopreservación , Trehalosa , Supervivencia Celular , Crioprotectores/farmacología , Congelación , Humanos , Masculino , Trehalosa/farmacología
17.
ACS Macro Lett ; 9(11): 1687-1692, 2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-35617071

RESUMEN

Hypoxia-activated prodrugs (HAPs) have emerged as important candidates for chemotherapy due to their efficient killing of hypoxic cancer cells. Traditional small molecule agents, such as tirapazamine (TPZ) and its derivatives, have shown unsatisfactory therapeutic effect in clinical trials due to poor bioavailability in hypoxic tumor regions. Herein, an amphiphilic macromolecular prodrug with hypoxia-specific activity, named as hypoxia-activated macromolecular prodrug (HAMP), is prepared from poly{[poly(ethylene glycol) methacrylate]-st-(methacrylic acid)} [poly(PEGMA-st-MAA)], containing pendant TPZ residues. This polymer can self-assemble in an aqueous system into ∼37 nm sized nanoparticles. In vitro experiments indicated that HAMP shows 5× higher cytotoxicity to hypoxic cancer cells as compared to normoxic cancer cells. Therefore, the developed HAMP can be concurrently used with other therapeutic agents as a highly efficient hypoxia-activated agent.

18.
ACS Macro Lett ; 9(10): 1464-1470, 2020 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-35653664

RESUMEN

Although, various types of pharmaceuticals have been developed for cervical carcinomas, treatment with these drugs often results in a number of undesirable side effects, toxicity and multidrug resistance. Here, we aimed at modifying the genetic profiling of cancer cells by silencing the expression of the epidermal growth factor receptor (EGFR) gene. We have synthesized two kinds of RAFT-made, biocompatible, and cationic polymers for the encapsulation of silencing RNA (siRNA). This vector has a dual capability: it contains a cationic segment to complex with the siRNA and an omega-end modified with an oxaborole group via thiol-ene click chemistry that responds to the acidic tumor microenvironment. This structural innovation enables this macromolecule to interact with multiple polyplexes and release the siRNA in a mild acidic environment. A strategy that has shown enhanced gene silencing without elevating the cytotoxicity of the system, as determined by Western blot analysis. The success of this approach has afforded further interest in utilizing boron-carbohydrate interaction in the development of nonviral vectors for gene therapy.

19.
Biomacromolecules ; 20(5): 2068-2074, 2019 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-30970212

RESUMEN

The ErbB family of proteins, structurally related to the epidermal growth factor receptor (EGFR), is found to be overexpressed in many cancers such as gliomas, a lung and cervical carcinomas. Gene therapy allows to modify the expression of genes like ErbB and has been a promising strategy to target oncogenes and tumor suppressor genes. In the current work, novel hydroxyl-rich poly(glycidyl methacrylate) (PGMA)-based cationic glycopolymers were designed for intracellular small interfering RNA (siRNA) delivery to silence the EGFR gene. The cationic polymers with different sugar decoration degrees (0, 9, and 33%) were synthesized by ring-opening reaction of PGMA with ethanolamine and a lactobionic acid-derived aminosaccharide (Lac-NH2). Specific EGFR knockdown of the protein tyrosine kinase ErbB-overexpressing HeLa cells was achieved using these hydroxyl-rich polycation/siRNA complexes. Higher sugar content improved the biocompatibility of the polymers, but it also seems to decrease the EGFR knockdown capability, which should mainly be related to the surface charge of polyplexes. An optimum balance was observed with PGEL-1 (9% sugar content) formulation, achieving ∼52% knockdown efficiency as well as high cell viability. Considering the specific recognition between galactose residues and asialoglycoprotein receptor in hepatocytes, our novel PGMA-based cationic glycopolymers exhibited promising future to serve as a safe and targeting gene delivery vector to hepatoma cell line like HepG2.


Asunto(s)
Carbohidratos/química , Técnicas de Transferencia de Gen , Ácidos Polimetacrílicos/química , ARN Interferente Pequeño/genética , Cationes/química , Receptores ErbB/genética , Receptores ErbB/metabolismo , Etanolamina/química , Células HeLa , Células Hep G2 , Humanos
20.
Biomacromolecules ; 20(2): 1028-1035, 2019 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-30596492

RESUMEN

Hydrogels that are injectable, self-healing, and multiresponsive are becoming increasingly relevant for a wide range of applications. In this work, we have successfully developed a novel approach in the fabrication of smart hydrogels with all the above properties. A symmetrical ABA triblock copolymer was first synthesized via atom transfer radical polymerization with a temperature responsive middle block and two permanently hydrophilic glycopolymer chains on both ends. Hydrogels were subsequently constructed by mixing the triblock copolymer with another linear hydrophilic copolymer bearing benzoxaborole groups. The interactions of the benzoxaborole groups with the sugar hydroxyl groups allowed the formation of dynamic covalent bonds. The resulting hydrogels exhibited temperature, pH, and sugar responsiveness. Rheological studies confirmed that the mechanical property can be tuned by changing the pH as well as the galactose/benzoxaborole molar ratio. Furthermore, the hydrogels showed excellent self-healing ability and shear-thinning performance due to the inherent well-known dynamic covalent bonds of boronic esters. Therefore, these types of hydrogels can have excellent biomedical applications.


Asunto(s)
Hidrogeles/química , Ácidos Borónicos/química , Galactosa/química , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Polimerizacion , Polímeros/química , Reología/métodos , Azúcares/química , Temperatura
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