ABSTRACT
BACKGROUND: Colorectal cancer is a common disease worldwide with non-specific symptoms such as blood in the stool, bowel movements, weight loss and fatigue. Chemotherapy drugs can cause side effects such as nausea, vomiting and a weakened immune system. The use of antioxidants such as hesperidin could reduce the side effects, but its low bioavailability is a major problem. In this research, we aimed to explore the drug delivery and efficiency of this antioxidant on the HCT116 colorectal cancer cell line by loading hesperidin into PLGA nanoparticles. MATERIALS AND METHODS: Hesperidin loaded PLGA nanoparticles were produced by single emulsion evaporation method. The physicochemical properties of the synthesized hesperidin-loaded nanoparticles were determined using SEM, AFM, FT-IR, DLS and UV-Vis. Subsequently, the effect of the PLGA loaded hesperidin nanoparticles on the HCT116 cell line after 48 h was investigated by MTT assay at three different concentrations of the nanoparticles. RESULT: The study showed that 90% of hesperidin were loaded in PLGA nanoparticles by UV-Vis spectrophotometry and FT-IR spectrum. The nanoparticles were found to be spherical and uniform with a hydrodynamic diameter of 76.2 nm in water. The release rate of the drug was about 93% after 144 h. The lowest percentage of cell viability of cancer cells was observed at a concentration of 10 µg/ml of PLGA nanoparticles loaded with hesperidin. CONCLUSION: The results indicate that PLGA nanoparticles loaded with hesperidin effectively reduce the survival rate of HCT116 colorectal cancer cells. However, further studies are needed to determine the appropriate therapeutic dosage and to conduct animal and clinical studies.
Subject(s)
Colorectal Neoplasms , Hesperidin , Nanoparticles , Polylactic Acid-Polyglycolic Acid Copolymer , Humans , Hesperidin/chemistry , Hesperidin/pharmacology , Hesperidin/administration & dosage , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Colorectal Neoplasms/drug therapy , HCT116 Cells , Nanoparticles/chemistry , Cell Survival/drug effects , Lactic Acid/chemistry , Polyglycolic Acid/chemistry , Drug Delivery Systems , Particle Size , Drug Carriers/chemistry , Spectroscopy, Fourier Transform Infrared , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Nanoparticle Drug Delivery System/chemistryABSTRACT
Antioxidant therapies are of interest in the prevention and management of ocular disorders such as cataracts. Although an active area of interest, topical therapy with antioxidants for the treatment of cataracts is complicated by multiple ocular anatomical barriers, product stability, and solubility. Entrapment and delivery of antioxidants with poly(lactic-co-glycolic acid) nanoparticles is a possible solution to these challenges, however, little is known regarding their effects in vitro or in vivo. Our first aim was to investigate the impact of blank and lutein loaded PLGA nanoparticles on viability and development of reactive oxygen species in lens epithelial cells in vitro. Photo-oxidative stress was induced by ultraviolet light exposure with cell viability and reactive oxygen species monitored. Next, an in vivo, selenite model was utilized to induce cataract formation in rodents. Eyes were treated topically with both free lutein and lutein loaded nanoparticles (LNP) at varying concentrations. Eyes were monitored for the development of anterior segment changes and cataract formation. The ability of nanodelivered lutein to reach the anterior segment of the eye was evaluated by liquid chromatography coupled to mass spectrometry of aqueous humor samples and liquid chromatography coupled to tandem mass spectrometry (targeted LC-MS/MS) of lenses. LNP had a minimal impact on the viability of lens epithelial cells during the short exposure timeframe (24 h) and at concentrations < 0.2 µg LNP/µl. A significant reduction in the development of reactive oxygen species was also noted. Animals treated with LNPs at an equivalent lutein concentration of 1,278 µg /mL showed the greatest reduction in cataract scores. Lutein delivery to the anterior segment was confirmed through evaluation of aqueous humor and lens sample evaluation. Topical treatment was not associated with the development of secondary keratitis or anterior uveitis when applied once daily for one week. LNPs may be an effective in the treatment of cataracts.
Subject(s)
Administration, Topical , Cataract , Lutein , Nanoparticles , Polylactic Acid-Polyglycolic Acid Copolymer , Animals , Lutein/pharmacology , Lutein/administration & dosage , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Nanoparticles/chemistry , Cataract/drug therapy , Rats , Lens, Crystalline/drug effects , Lens, Crystalline/metabolism , Reactive Oxygen Species/metabolism , Oxidative Stress/drug effects , Cell Survival/drug effects , Antioxidants/pharmacology , Antioxidants/administration & dosage , Humans , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Aqueous Humor/drug effects , Aqueous Humor/metabolism , Male , Cell Line , Lactic Acid/chemistry , Polyglycolic Acid/chemistryABSTRACT
End groups of poly(Lactide-co-glycolide) (PLGA) play an important role in determining the properties of polymers for use in drug delivery systems. For instance, it has been reported that the encapsulation efficiency in PLGA microspheres varies significantly between ester-terminated and acid-terminated PLGA. More importantly, the in-vivo degradation time of such polymer excipients is influenced by the functional end-group of the copolymer used. The end group distribution in PLGA polymers has been studied using electrospray and matrix-assisted laser-desorption/ionization - high-resolution mass spectrometry. In both cases, the application of these methods is typically limited to PLGA having a molecular weight of up to 4 kDa. 13Carbon-nuclear-magnetic-resonance has also been reported as a method to differentiate and quantify PLGA end groups with a molecular weight up to 136 kDa. However, reported NMR methods take over 12 h per sample, limiting throughput.Cryoprobe NMR can reduce the time required for the process, however such NMR equipment is costly, which makes it unsuitable for the quality control of PLGA. Here, we present a normal-phase liquid chromatography method capable of resolving functionality type distribution (FTD) and, partially, chemical composition distribution (CCD) in commercial PLGA polymers obtained from ring opening polymerization. This method can separate PLGA polymers with a molecular weight of up to 183.0 kDa while also enabling the simultaneous separation of the difference of Lactic acid (LA)/Glycolic acid (GA) ratios. To achieve this, a cross-linked diol column was used with a ternary gradient from HEX to 0.1 % v/v TEA in EA to 0.1 % v/v FA in THF to allow first for the elution of mono-ester terminated PLGA, followed by the di-acid terminated. In addition, a separation of ester-terminated PLGA in the difference of the LA/GA ratio was achieved. This method is expected to aid in understanding the correlation between PLGA's FTD, CCD, and physical properties, facilitating product development and quality control.
Subject(s)
Polyglycolic Acid , Polylactic Acid-Polyglycolic Acid Copolymer , Polyglycolic Acid/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Molecular Weight , Lactic Acid/chemistry , Chromatography, Liquid/methods , Magnetic Resonance Spectroscopy , Hydrogen-Ion ConcentrationABSTRACT
Imatinib is a chemotherapeutic agent known to cause severe side effects when administrated systemically. Encapsulating imatinib in co-polymer poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) offers a targeted drug delivery. In this work, PLGA 50:50 and PLGA 75:25 NPs encapsulated imatinib using the electrohydrodynamic atomisation technique. All particles generated were spherical with a smooth surface with a size distribution of 455±115 nm (PLGA 50:50) and 363±147 nm (PLGA 75:25). Encapsulation of imatinib was shown to be higher than 75 % and was shown to increase the zeta potential of the loaded NPs. The release of imatinib showed an initial burst in the first 12 h, followed by different sustained releases with up to 70 %. Both types of imatinib-loaded NPs' effect on cell viability and their cellular uptake were also studied on A549 cells, and the antiproliferative effect was comparable to that of cells treated with free drugs. Finally, Rhodamine-B-loaded NP-treated cells demonstrated the cellular uptake of NPs.
Subject(s)
Antineoplastic Agents , Cell Survival , Drug Carriers , Imatinib Mesylate , Nanoparticles , Particle Size , Polylactic Acid-Polyglycolic Acid Copolymer , Imatinib Mesylate/administration & dosage , Imatinib Mesylate/pharmacology , Imatinib Mesylate/pharmacokinetics , Humans , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Nanoparticles/chemistry , A549 Cells , Cell Survival/drug effects , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/pharmacology , Drug Carriers/chemistry , Drug Delivery Systems/methods , Lactic Acid/chemistry , Drug Liberation , Polyglycolic Acid/chemistry , Polymers/chemistry , Cell Line, TumorABSTRACT
Aim: This study focused on developing a topical gel incorporating lornoxicam-loaded poly(lactic-co-glycolic acid) and polyethylene glycol (PLGA-PEG) blend nanoparticles to mitigate gastrointestinal (GIT) side effects and enhance therapeutic efficacy. Materials & methods: Synthesized nanoparticles were subjected to in vitro characterization, ex vivo permeation studies, and acute oral toxicity analysis post-incorporation into the gel using a S/O/W double emulsion solvent. Results & conclusion: The nanoparticles displayed a smooth, spherical morphology (170-321 nm) with increased entrapment efficiency (96.2%). LOX exhibited a permeation rate of 70-94% from the nanoparticle-infused gel, demonstrating favorable biocompatibility at the cellular level. The formulated gel, enriched with nanoparticles, holds promising prospects for drug-delivery systems and promising improved therapeutic outcomes for LOX.
[Box: see text].
Subject(s)
Administration, Cutaneous , Nanoparticles , Piroxicam , Polyethylene Glycols , Polylactic Acid-Polyglycolic Acid Copolymer , Piroxicam/analogs & derivatives , Piroxicam/administration & dosage , Piroxicam/chemistry , Polyethylene Glycols/chemistry , Animals , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Nanoparticles/chemistry , Humans , Drug Carriers/chemistry , Particle Size , Inflammation/drug therapy , Drug Delivery Systems , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Mice , Lactic Acid/chemistry , Male , Rats , Polyglycolic Acid/chemistry , Skin/metabolism , Skin/drug effectsABSTRACT
We investigated the single particle kinetics of the molecular release processes from two types of microcapsules used as drug delivery systems (DDS): biodegradable poly(lactic-co-glycolic) acid (PLGA) and a light-triggered-degradable liposome encapsulating gold nanospheres (liposome-GNP). To optimize the design of DDS capsules, it is highly desirable to develop a method for real-time monitoring of the release process. Using a combination of optical tweezers and confocal fluorescence microspectroscopy we successfully analyzed a single optically trapped PLGA particle and liposome-GNPs in solution. From temporal decay profiles of the fluorescence intensity, we determined the time constant τ of the release processes. We demonstrated that the release rate of spontaneously degradable microcapsules (PLGA) decreased with increasing size, while conversely, the release rate of external stimuli-degradable microcapsules (liposome-GNPs) increased in proportion to their size. This result is explained by the differences in the disruption mechanisms of the capsules, with PLGA undergoing hydrolysis and the GNPs in the liposome-GNP undergoing a photoacoustic effect under nanosecond pulsed laser irradiation. The present approach offers a way forward to an alternative microanalysis system for single drug delivery nanocarriers.
Subject(s)
Gold , Lactic Acid , Liposomes , Nanospheres , Optical Tweezers , Polyglycolic Acid , Polylactic Acid-Polyglycolic Acid Copolymer , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Gold/chemistry , Liposomes/chemistry , Lactic Acid/chemistry , Nanospheres/chemistry , Polyglycolic Acid/chemistry , Particle Size , Drug Delivery SystemsABSTRACT
In recent years, the research on the conversion of chitin to high value-added chemicals has attracted more and more attention. At present, the method of preparing lactic acid from chitin mostly uses strong base or catalyst. The reaction system under alkaline condition not only corrodes the container but also easily harms the human body. Herein, a simple and effective method to convert chitin to organic acids in catalyst and base-free conditions is developed. The use of H2O2 only can efficiently convert chitin to organic acids in the absence of bases and catalysts. Under the optimal conditions of 30 mg chitin, 2.1 mL water, 0.9 mL H2O2 at 230 °C for 1.5 h, the lactic acid yield of chitin can reach 58.2 % and the total organic acid yield can reach 84.0 %. This work provides an efficient method for the resource utilization of chitin biomass.
Subject(s)
Chitin , Hydrogen Peroxide , Lactic Acid , Oxidation-Reduction , Chitin/chemistry , Hydrogen Peroxide/chemistry , Catalysis , Lactic Acid/chemistryABSTRACT
Periprosthetic infection is one of the most devastating complications following orthopaedic surgery. Rapid detection of an infection can change the treatment pathway and improve outcomes for the patient. In here, we propose a miniaturized lactate biosensor developed on a flexible substrate and integrated on a small-form bone implant to detect infection. The methods for lactate biosensor fabrication and integration on a bone implant are fully described within this study. The system performance was comprehensively electrochemically characterised, including with L-lactate solutions prepared in phosphate-buffered saline and culture medium, and interferents such as acetaminophen and ascorbic acid. A proof-of-concept demonstration was then conducted with ex vivo ovine femoral heads incubated with and without exposure to Staphylococcus epidermidis. The sensitivity, current density and limit-of-detection levels achieved by the biosensor were 1.25 µA mM-1, 1.51 µA.M-1.mm-2 and 66 µM, respectively. The system was insensitive to acetaminophen, while sensitivity to ascorbic acid was half that of the sensitivity to L-lactate. In the ex vivo bone model, S. epidermidis infection was detected within 5 h of implantation, while the control sample led to no change in the sensor readings. This pioneering work demonstrates a pathway to improving orthopaedic outcomes by enabling early infection diagnosis.
Subject(s)
Biosensing Techniques , Lactic Acid , Staphylococcal Infections , Staphylococcus epidermidis , Surgical Wound Infection , Biosensing Techniques/methods , Animals , Staphylococcus epidermidis/isolation & purification , Sheep , Staphylococcal Infections/diagnosis , Surgical Wound Infection/diagnosis , Lactic Acid/analysis , Lactic Acid/chemistry , Humans , Wireless Technology , Prostheses and Implants , Equipment Design , Prosthesis-Related Infections , Enzymes, Immobilized/chemistry , Orthopedics , Mixed Function OxygenasesABSTRACT
A novel optical lactate biosensor is presented that utilizes a colorimetric interaction between H2O2 liberated by a binary enzymatic reaction and bis(neocuproine)copper(II) complex ([Cu(Nc)2]2+) known as CUPRAC (cupric reducing antioxidant capacity) reagent. In the first step, lactate oxidase (LOx) and pyruvate oxidase (POx) were separately immobilized on silanized magnetite nanoparticles (SiO2@Fe3O4 NPs), and thus, 2 mol of H2O2 was released per 1 mol of the substrate due to a sequential enzymatic reaction of the mixture of LOx-SiO2@Fe3O4 and POx-SiO2@Fe3O4 NPs with lactate and pyruvate, respectively. In the second step, the absorbance at 450 nm of the yellow-orange [Cu(Nc)2]+ complex formed through the color reaction of enzymatically produced H2O2 with [Cu(Nc)2]2+ was recorded. The results indicate that the developed colorimetric binary enzymatic biosensor exhibits a broad linear range of response between 0.5 and 50.0 µM for lactate under optimal conditions with a detection limit of 0.17 µM. The fabricated biosensor did not respond to other saccharides, while the positive interferences of certain reducing compounds such as dopamine, ascorbic acid, and uric acid were minimized through their oxidative removal with a pre-oxidant (NaBiO3) before enzymatic and colorimetric reactions. The fabricated optical biosensor was applied to various samples such as artificial blood, artificial/real sweat, and cow milk. The high recovery values (close to 100%) achieved for lactate-spiked samples indicate an acceptable accuracy of this colorimetric biosensor in the determination of lactate in real samples. Due to the increase in H2O2 production with the bienzymatic lactate sensor, the proposed method displays double-fold sensitivity relative to monoenzymatic biosensors and involves a neat color reaction with cupric-neocuproine having a clear stoichiometry as opposed to the rather indefinite stoichiometry of analogous redox dye methods.
Subject(s)
Biosensing Techniques , Colorimetry , Copper , Enzymes, Immobilized , Hydrogen Peroxide , Lactic Acid , Magnetite Nanoparticles , Mixed Function Oxygenases , Pyruvate Oxidase , Biosensing Techniques/methods , Colorimetry/methods , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Mixed Function Oxygenases/chemistry , Mixed Function Oxygenases/metabolism , Copper/chemistry , Magnetite Nanoparticles/chemistry , Pyruvate Oxidase/chemistry , Pyruvate Oxidase/metabolism , Lactic Acid/analysis , Lactic Acid/chemistry , Hydrogen Peroxide/chemistry , Limit of Detection , Animals , Silicon Dioxide/chemistry , PhenanthrolinesABSTRACT
Combining proton and phosphorus magnetic resonance spectroscopy offers a unique opportunity to study the oxidative and glycolytic components of metabolism in working muscle. This paper presents a 7 T proton calf coil design that combines dipole and loop elements to achieve the high performance necessary for detecting metabolites with low abundance and restricted visibility, specifically lactate, while including the option of adding a phosphorus array. We investigated the transmit, receive, and parallel imaging performance of three transceiver dipoles with six pair-wise overlap-decoupled standard or twisted pair receive-only coils. With a higher SNR and more efficient transmission decoupling, standard loops outperformed twisted pair coils. The dipoles with standard loops provided a four-fold-higher image SNR than a multinuclear reference coil comprising two proton channels and 32% more than a commercially available 28-channel proton knee coil. The setup enabled up to three-fold acceleration in the right-left direction, with acceptable g-factors and no visible aliasing artefacts. Spectroscopic phantom measurements revealed a higher spectral SNR for lactate with the developed setup than with either reference coil and fewer restrictions in voxel placement due to improved transmit homogeneity. This paper presents a new use case for dipoles and highlights their advantages for the integration in multinuclear calf coils.
Subject(s)
Magnetic Resonance Imaging , Muscle, Skeletal , Phantoms, Imaging , Humans , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/chemistry , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy/methods , Signal-To-Noise Ratio , Lactic Acid/chemistry , Lactic Acid/metabolismABSTRACT
In this paper, a novel fluorescent detection method for glucose and lactic acid was developed based on fluorescent iron nanoclusters (Fe NCs). The Fe NCs prepared using hemin as the main raw material exhibited excellent water solubility, bright red fluorescence, and super sensitive response to hydrogen peroxide (H2O2). This paper demonstrates that Fe NCs exhibit excellent peroxide-like activity, catalyzing H2O2 to produce hydroxyl radicals (â¢OH) that can quench the red fluorescence of Fe NCs. In this paper, a new type of glucose sensor was established by combining Fe NCs with glucose oxidase (GluOx). With the increase in glucose content, the fluorescence of Fe NCs decreases correspondingly, and the glucose content can be detected in the scope of 0-200 µmol·L-1 (µM). Similarly, the lactic acid sensor can also be established by combining Fe NCs with lactate oxidase (LacOx). With the increase in lactic acid concentration, the fluorescence of Fe NCs decreases correspondingly, and the lactic acid content can be detected in the range of 0-100 µM. Furthermore, Fe NCs were used in the preparation of gel test strip, which can be used to detect H2O2, glucose and lactic acid successfully by the changes of fluorescent intensity.
Subject(s)
Glucose Oxidase , Glucose , Hydrogen Peroxide , Iron , Lactic Acid , Lactic Acid/analysis , Lactic Acid/chemistry , Glucose/analysis , Glucose/chemistry , Hydrogen Peroxide/chemistry , Hydrogen Peroxide/analysis , Iron/chemistry , Glucose Oxidase/chemistry , Glucose Oxidase/metabolism , Biosensing Techniques/methods , Fluorescence , Spectrometry, Fluorescence/methods , Fluorescent Dyes/chemistry , Mixed Function Oxygenases/chemistry , Mixed Function Oxygenases/metabolism , Metal Nanoparticles/chemistryABSTRACT
Polymeric delivery systems could enable the fast- and low-side-effect transport of various RNA classes. Previously, we demonstrated that polyvinylamine (PVAm), a cationic polymer, transfects many kinds of RNAs with high efficiency and low toxicity both in vitro and in vivo. The modification of poly lactic-co-glycolic acid (PLGA) with cartilage-targeting peptide (CAP) enhances its stiffness and tissue-specific delivery of RNA to overcome the avascular nature of articular cartilage. Here we describe the protocol to use PVAm as an RNA carrier, and further, by modifying PVAm with PLGA and CAP, the corresponding co-polymer could be applied for functional RNA delivery for osteoarthritis treatment.
Subject(s)
Polylactic Acid-Polyglycolic Acid Copolymer , Polyvinyls , Polyvinyls/chemistry , Animals , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Humans , Lactic Acid/chemistry , Transfection/methods , Gene Transfer Techniques , Polyglycolic Acid/chemistry , Drug Carriers/chemistry , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/genetics , Osteoarthritis/drug therapyABSTRACT
This work employs nitrogen plasma immersion ion implantation (PIII) to modify electrospinning polylactic acid membranes and immobilizes basic fibroblast growth factors (bFGF) by forming crosslinking bonds. The study investigates the modified membranes' surface characteristics and the stimulatory effects of crosslinked bFGF polylactic acid membranes on osteoblast and fibroblast proliferation. The PIII process occurs under low vacuum conditions and is controlled by processing time and power pulse width. The experimental results indicate that, within a 400-second N2-PIII treatment, the spun fibers remain undamaged, demonstrating an increase in hydrophilicity (from 117° to 38°/36°) and nitrogen content (from 0% to 7.54%/8.05%). X-ray photoelectron spectroscopy analysis suggests the formation of a C-N-C=O crosslinked bond. Cell culture and activity assessments indicate that the PIII-treated and crosslinked bFGF film exhibits significantly higher cell growth activity (p < 0.05) than the untreated group. These intergroup differences are attributed to the surface crosslinking bond content. In osteogenic induction, the results for each day show that the treated group performs better. However, the intergroup disparities within the crosslinked bFGF group disappear with prolonged culture time due to the rapid osteogenesis prompted by bFGF. The findings suggest that PIII treatment of electrospinning polylactic acid membranes holds promise in promoting osteogenesis in bone tissue scaffolds.
Subject(s)
Biocompatible Materials , Cell Differentiation , Cell Proliferation , Nanofibers , Osteoblasts , Nanofibers/chemistry , Osteoblasts/cytology , Osteoblasts/drug effects , Osteoblasts/metabolism , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Biocompatible Materials/pharmacology , Biocompatible Materials/chemistry , Animals , Polyesters/chemistry , Polyesters/pharmacology , Fibroblast Growth Factor 2/pharmacology , Fibroblast Growth Factor 2/chemistry , Plasma Gases/pharmacology , Mice , Osteogenesis/drug effects , Lactic Acid/chemistry , Lactic Acid/pharmacology , Photoelectron SpectroscopyABSTRACT
Poly(l-lactic acid) (PLA) is a biodegradable bioplastic with limited marine degradation. This study examines the impact of molecular weight on PLA's marine biodegradability. We synthesized PLA with terminal hydroxyl groups (PLA-OH) with degrees of polymerization (DP) between 14 and 642 and conducted biochemical oxygen demand (BOD) tests. Samples with a DP of 422 or 642 did not degrade, like commercial PLA. However, PLA-OH with a DP below 314 showed biodegradability, with DP 14 exhibiting a higher degradability than cellulose. Size exclusion chromatography (SEC) confirmed a decrease in molecular weight for samples with DPs below 314, indicating extracellular microbial activity. These findings suggest that PLA-OH with a DP under 314 can be degraded in marine conditions, unlike high-molecular-weight PLA. If the DP of high-molecular-weight PLA can be reduced to 314 by some specific method, then it is expected that PLA can be used to create marine biodegradable materials.
Subject(s)
Biodegradation, Environmental , Molecular Weight , Polyesters , Polyesters/chemistry , Polyesters/metabolism , Polymers/chemistry , Polymers/metabolism , Lactic Acid/chemistry , Lactic Acid/metabolism , Chromatography, GelABSTRACT
Tympanic membrane perforation (TMP) is prevalent in clinical settings. Patients with TMPs often suffer from infections caused by Staphylococcus aureus and Pseudomonas aeruginosa, leading to middle ear and external ear canal infections, which hinder eardrum healing. The objective of this study is to fabricate an enzyme-responsive antibacterial electrospun scaffold using poly(lactic-co-glycolic acid) and hyaluronic acid for the treatment of infected TMPs. The properties of the scaffold were characterized, including morphology, wettability, mechanical properties, degradation properties, antimicrobial properties, and biocompatibility. The results indicated that the fabricated scaffold had a core-shell structure and exhibited excellent mechanical properties, hydrophobicity, degradability, and cytocompatibility. Furthermore, in vitro bacterial tests and ex vivo investigations on eardrum infections suggested that this scaffold possesses hyaluronidase-responsive antibacterial properties. It may rapidly release antibiotics when exposed to the enzyme released by S. aureus and P. aeruginosa. These findings suggest that the scaffold has great potential for repairing TMPs with infections.
Subject(s)
Anti-Bacterial Agents , Hyaluronic Acid , Hyaluronoglucosaminidase , Polylactic Acid-Polyglycolic Acid Copolymer , Pseudomonas aeruginosa , Staphylococcus aureus , Tissue Scaffolds , Tympanic Membrane , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Hyaluronoglucosaminidase/metabolism , Hyaluronoglucosaminidase/chemistry , Staphylococcus aureus/drug effects , Tissue Scaffolds/chemistry , Pseudomonas aeruginosa/drug effects , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Polylactic Acid-Polyglycolic Acid Copolymer/pharmacology , Hyaluronic Acid/chemistry , Hyaluronic Acid/pharmacology , Animals , Humans , Polyglycolic Acid/chemistry , Polyglycolic Acid/pharmacology , Lactic Acid/chemistry , Lactic Acid/pharmacology , Tympanic Membrane Perforation/drug therapy , Tympanic Membrane Perforation/therapy , Microbial Sensitivity TestsABSTRACT
Over the past decade, the preparation of novel materials by enzyme-embedding into biopolyesters has been proposed as a straightforward method to produce self-degrading polymers. This paper reports the preparation and enzymatic degradation of extruded self-degradable films of three different biopolyesters: poly(lactic acid) (PLA), poly(butylene adipate-co-terephthalate) (PBAT), and poly(butylene succinate) (PBS), as well as three binary/ternary blends. Candida antarctica lipase B (CalB) has been employed for the enzyme-embedding procedure, and to the best of our knowledge, the use of this approach in biopolyester blends has not been reported before. The three homopolymers exhibited differentiated degradation and suggested a preferential attack of CalB on PBS films over PBAT and PLA. Moreover, the self-degradable films obtained from the blends showed slow degradation, probably due to the higher content in PLA and PBAT. These observations pave the way for exploring enzymes capable of degrading all blend components or an enzymatic mixture for blend degradation.
Subject(s)
Fungal Proteins , Lipase , Polyesters , Lipase/chemistry , Lipase/metabolism , Polyesters/chemistry , Fungal Proteins/chemistry , Fungal Proteins/metabolism , Polymers/chemistry , Lactic Acid/chemistry , Enzymes, Immobilized/chemistry , Butylene GlycolsABSTRACT
The objective of this study was to explore the use of nanosized/micronized sugar particles as porogens for preparing porous poly(lactide-co-glycolide) (PLGA) microparticles by a solid-in-oil-in-water (S/O/W) solvent evaporation method. Porous PLGA microparticles containing dexamethasone were prepared with different nanosized/micronized sugars (sucrose, trehalose and lactose), types of PLGA, and osmogens (NaCl or sucrose) in the external water phase. The microparticles were characterized for morphology, thermal properties, particle size, surface area, encapsulation efficiency and drug release/swelling during release. The addition of nanosized/micronized sugar particles resulted in porous PLGA microparticles with high encapsulation efficiencies. The porosity of the microparticles was caused both by the influx of water into the polymer droplets and the encapsulation and subsequent dissolution of sugar particles during the manufacturing process. The porosity (pore size) of the microparticles and, as a result, the drug release pattern could be well controlled by the particle size and weight fraction of the sugar particles. Because of a larger inner surface area, nanosized sugar particles were more efficient porogen than micronized sugar particles to obtain porous PLGA microparticles with flexible release patterns.
Subject(s)
Dexamethasone , Drug Liberation , Lactic Acid , Nanoparticles , Particle Size , Polyglycolic Acid , Polylactic Acid-Polyglycolic Acid Copolymer , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Porosity , Lactic Acid/chemistry , Nanoparticles/chemistry , Polyglycolic Acid/chemistry , Dexamethasone/chemistry , Dexamethasone/administration & dosage , Sugars/chemistry , Microspheres , Drug Carriers/chemistry , Trehalose/chemistryABSTRACT
Nanoparticles based on poly(lactic-co-glycolic acid) (PLGA) with various surface chemistry are widely used in biomedicine for theranostic applications. The nature of the external coating of nanoparticles has a significant influence on their efficiency as drug carriers or visualization agents. However, information about the mechanisms of nanoparticle accumulation in tumors and the influence of their surface properties on biodistribution is scarce due to the lack of systematic evaluation. Here we investigate the effect of different polymer coatings of the surface on in vitro and in vivo properties of PLGA nanoparticles. Namely, cell binding efficiency, cytotoxicity, efficiency of fluorescent bioimaging, and tumor accumulation were tested. The highest binding efficiency in vitro and cytotoxicity were observed for positively charged polymers. Interestingly, in vivo fluorescent visualization of tumor-bearing mice and quantitative measurements of biodistribution of magnetite-loaded nanoparticles indicated different dependences of accumulation in tumors on the coating of PLGA nanoparticles. This means that nanoparticle surface properties can simultaneously enhance imaging efficiency and decrease quantitative accumulation in tumors. The obtained data demonstrate the complexity of the dependence of nanoparticles' effectiveness for theranostic applications on surface features. We believe that this study will contribute to the rational design of nanoparticles for effective cancer diagnostics and therapy.
Subject(s)
Drug Carriers , Nanoparticles , Polylactic Acid-Polyglycolic Acid Copolymer , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Animals , Mice , Tissue Distribution , Nanoparticles/chemistry , Drug Carriers/chemistry , Humans , Cell Line, Tumor , Lactic Acid/chemistry , Surface Properties , Polymers/chemistry , Polyglycolic Acid/chemistry , FemaleABSTRACT
Polymer-based scaffolds with different degradability have been investigated to screen the matrix whose degradation rate is more closely matched with the bone regeneration rate. However, these comparisons are inclined to be compromised by the animal individual differences. In this study, we constructed an integrated scaffold model comprising four parts with different degradability and bioactivity to achieve an in situ comparison of bone regeneration ability of different scaffolds. Slow-degradable polycaprolactone (PCL), fast-degradable poly (lactic-co-glycolic acid) (PLGA), and silica-coated PCL and PLGA scaffolds were assembled into a round sheet to form a hydroxyapatite (HA)-free integrated scaffold. HA-doped PCL, PLGA, and silica-coated PCL and PLGA scaffolds were assembled to create an HA-incorporated integrated scaffold. The in vivo experimental results demonstrated that the local acid microenvironment caused by the rapid degradation of PLGA interfered with the osteogenic process promoted by PCL-based scaffolds in defect areas implanted with HA-free integrated scaffolds. Since the incorporation of HA alleviated the acidic microenvironment to some extent, each scaffold in HA-incorporated scaffolds exhibited its expected bone regeneration capacity. Consequently, it is feasible to construct an integrated structure for comparing the osteogenic effects of various scaffolds in situ, when there is no mutual interference between the materials. The strategy presented in this study inspired the structure design of biomaterials to enable in situ comparison of bone regeneration capacity of scaffolds.
Subject(s)
Durapatite , Osteogenesis , Polyesters , Polylactic Acid-Polyglycolic Acid Copolymer , Tissue Scaffolds , Tissue Scaffolds/chemistry , Osteogenesis/drug effects , Animals , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Polyesters/chemistry , Durapatite/chemistry , Bone Regeneration/drug effects , Polymers/chemistry , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Polyglycolic Acid/chemistry , Tissue Engineering/methods , Lactic Acid/chemistryABSTRACT
Cancer immunotherapy remains a significant challenge due to insufficient proliferation of immune cells and the sturdy immunosuppressive tumor microenvironment. Herein, we proposed the hypothesis of cuproptosis-lactate regulation to provoke cuproptosis and enhance anti-tumor immunity. For this purpose, copper-human serum albumin nanocomplex loaded gold nanocages with bacterial membrane coating (BAu-CuNCs) were developed. The targeted delivery and disassembly of BAu-CuNCs in tumor cells initiated a cascade of reactions. Under near infrared (NIR) laser irradiation, the release of copper-human serum albumin (Cu-HSA) was enhanced that reacted with intratumoral glutathione (GSH) via a disulfide exchange reaction to liberate Cu2+ ions and exert cuproptosis. Subsequently, the cuproptosis effect triggered immunogenic cell death (ICD) in tumor by the release of damage associated molecular patterns (DAMPs) to realize anti-tumor immunity via robust production of cytotoxic T cells (CD8+) and helper T cells (CD4+). Meanwhile, under NIR irradiation, gold nanocages (AuNCs) promoted excessive reactive oxygen species (ROS) generation that played a primary role in inhibiting glycolysis, reducing the lactate and ATP level. The combine action of lower lactate level, ATP reduction and GSH depletion further sensitized the tumor cells to cuproptosis. Also, the lower lactate production led to the significant blockage of immunosuppressive T regulatory cells (Tregs) and boosted the anti-tumor immunity. Additionally, the effective inhibition of breast cancer metastasis to the lungs enhanced the anti-tumor therapeutic impact of BAu-CuNCs + NIR treatment. Hence, BAu-CuNCs + NIR concurrently induced cuproptosis, ICD and hindered lactate production, leading to the inhibition of tumor growth, remodeling of the immunosuppressive tumor microenvironment and suppression of lung metastasis. Therefore, leveraging cuproptosis-lactate regulation, this approach presents a novel strategy for enhanced tumor immunotherapy.