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1.
Int J Biol Macromol ; 267(Pt 1): 131539, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608994

RESUMEN

Sustainable strategies to improve the water resistance of cellulose paper are actively sought. In this work, polymeric microspheres (PMs), prepared through emulsion polymerization of cellulose nanofibers stabilized rubber seed oil-derived monomer, were investigated as coatings on corrugated medium paper (CMP). After infiltrating porous paper with PMs, the water-resistant corrugated papers (WRCPn) with enhanced mechanical properties were obtained. When 30 wt% PMs were introduced, WRCP30 turned out to be highly compacted with an increased water contact angle of 106.3° and a low water vapor transmission rate of 81 g/(m2 d) at 23 °C. Meanwhile, the tensile strength of WRCP30 increased to 22.2 MPa, a 4-fold increase from CMP. When tested in a well-hydrated state, 71% of its mechanical strength in the dry state was maintained. Even with a low content of 10 wt% PMs, WRCP10 also exhibited stable tensile strength and water wettability during the cyclic soaking-drying process. Thus, the plant oil based sustainable emulsion polymers provide a convenient route for enhancing the overall performance of cellulose paper.


Asunto(s)
Celulosa , Microesferas , Aceites de Plantas , Resistencia a la Tracción , Agua , Celulosa/química , Agua/química , Aceites de Plantas/química , Papel , Humectabilidad , Polímeros/química , Emulsiones/química , Porosidad , Nanofibras/química
2.
Int J Biol Macromol ; 265(Pt 2): 131059, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38521338

RESUMEN

Bone matrix vesicles are commonly acknowledged as the primary site of biomineralization in human skeletal tissue. Black phosphorus has exhibited favorable properties across various chemical and physical domains. In this investigation, a novel composite microsphere was synthesized through the amalgamation of sodium alginate (ALG) with black phosphorus nanosheets (BP) utilizing the electrospray (ES) technique. These microspheres were tailored to mimic the regulatory function of matrix vesicles (MV) upon exposure to a biomimetic mineralization fluid (SBF) during the biomineralization process. Results revealed that black phosphorus nanosheets facilitated the generation of hydroxyapatite (HA) on the microsphere surface. Live-dead assays and cell proliferation experiments showcased a cell survival rate exceeding 85 %. Moreover, wound healing assessments unveiled that M-ALG-BP microspheres exhibited superior migration capacity, with a migration rate surpassing 50 %. Furthermore, after 7 days of osteogenic induction, M-ALG-BP microspheres notably stimulated osteoblast differentiation. Particularly noteworthy, M-ALG-BP microspheres significantly enhanced osteogenic differentiation of osteoblasts and induced collagen production in vitro. Additionally, experiments involving microsphere implantation into mouse skeletal muscle demonstrated the potential for ectopic mineralization by ALG-BP microspheres. This investigation underscores the outstanding mineralization properties of ALG-BP microspheres and their promising clinical prospects in bone tissue engineering.


Asunto(s)
Matriz Ósea , Osteogénesis , Ratones , Animales , Humanos , Microesferas , Fósforo , Regeneración Ósea , Alginatos/farmacología , Alginatos/química
3.
Biosystems ; 237: 105175, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38460836

RESUMEN

Proteinoid-neuron networks combine biological neurons with spiking proteinoid microspheres, which are generated by thermal condensation of amino acids. Complex and dynamic spiking patterns in response to varied stimuli make these networks suitable for unconventional computing. This research examines the interaction of proteinoid-neuron networks with function-generator-artificial neural networks (ANN) that may create distinct electrical waveforms. Function-generator- artificial neural network (ANN) stimulates and modulates proteinoid-neuron network spiking activity and synchronisation to encode and decode information. We employ function-generator-ANN to study proteinoid-neuron network nonlinear dynamics and chaos and optimise their performance and energy efficiency. Function-generator-ANN improves proteinoid-neuron networks' computational capacities and robustness and creates unique hybrid systems with electrical devices. We address the benefits as well as the drawbacks of employing proteinoid-neuron networks for unconventional computing with function-generator-ANN.


Asunto(s)
Aminoácidos , Proteínas , Proteínas/metabolismo , Redes Neurales de la Computación , Neuronas/metabolismo
4.
Biomed Mater ; 19(3)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38387046

RESUMEN

Transcatheter arterial embolization plays a pivotal role in treating various diseases. However, the efficacy of embolization therapy in cancer treatment can be limited by several factors, such as inevitable incomplete or non-target embolization, and the tumor recurrence and metastasis caused by the hypoxic microenvironment. Moreover, it is essential to explore simpler, more economical, and efficient methods for microsphere synthesis. Herein, we achieved one-step photocatalytic synthesis of lipiodol-doped Fe3O4@Poly (diallyliso-phthalate) multifunctional microspheres (IFeD MS) for arterial embolization, chemotherapy, and imaging. The prepared microspheres are in the shape of dried plums, with a particle size of 100-300 µm. Lipiodol demonstrates a certain degree of chemotherapeutic activity, and the incorporation of Fe3O4enables the microspheres to exhibit magnetothermal response and magnetic resonance imaging capabilities. Furthermore, the radiopaque characteristics of both agents provide the microspheres with promising potential for computed tomography and digital radiography imaging. The renal embolization experiment in rabbits demonstrated that IFeD MS achieved significant embolization and chemotherapeutic effects. Biocompatibility experiments revealed that this embolic agent did not induce tissue damage or inflammation beyond the treatment area. Additionally, IFeD MS exhibited promising imaging potential. The results of this study imply that the developed multifunctional embolic agent IFeD MS may have significant potential in transforming tumors previously only suitable for palliative cares into resectable radical treatments.


Asunto(s)
Embolización Terapéutica , Aceite Etiodizado , Ácidos Ftálicos , Animales , Conejos , Microesferas , Embolización Terapéutica/métodos , Riñón
5.
Micromachines (Basel) ; 15(1)2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38258241

RESUMEN

The purpose of this study is to explore the possibility of using graphene-zinc oxide-hydroxyapatite (GO/ZnO/nHAp) composite microspheres as bone regeneration materials by making use of the complementary advantages of nanocomposites, so as to provide reference for the clinical application of preventing and solving bacterial infection after implantation of synthetic materials. Firstly, GO/ZnO composites and hydroxyapatite nanoparticles were synthesized using the hydrothermal method, and then GO/ZnO/nHAp composite microspheres were prepared via high-temperature sintering. The graphene-zinc oxide-calcium phosphate composite microspheres were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), energy dispersion spectroscopy (EDS), water contact angle measurement, degradation and pH determination, and differential thermal analysis (DiamondTG/DTA). The biocompatibility, osteogenic activity, and antibacterial activity of GO/ZnO/nHAp composite microspheres were further studied. The results of the cell experiment and antibacterial experiment showed that 0.5% and 1% GO-ZnO-nHAp composite microspheres not only had good biocompatibility and osteogenic ability but also inhibited Escherichia coli and Staphylococcus aureus by more than 45% and 70%. Therefore, GO/ZnO/nHAp composite microspheres have good physical and chemical properties and show good osteogenic induction and antibacterial activity, and this material has the possibility of being used as a bone regeneration material.

6.
Nanotechnology ; 35(15)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38150725

RESUMEN

Obesity has become an ongoing global crisis, since it increases the risks of cardiovascular disease, type 2 diabetes, fatty liver, cognitive decline, and some cancers. Adipose tissue is closely associated with the disorder of lipid metabolism. Several efforts have been made toward the modulation of lipid accumulation, but have been hindered by poor efficiency of cellular uptake, low safety, and uncertain effective dosage. Herein, we design an Fe3O4microsphere-doped composite hydrogel (Fe3O4microspheres @chitosan/ß-glycerophosphate/collagen), termed as Fe3O4@Gel, as the magnetocaloric agent for magnetic hyperthermia therapy (MHT), aiming to promote lipolysis in white adipocytes. The experimental results show that the obtained Fe3O4@Gel displays a series of advantages, such as fast sol-gel transition, high biocompatibility, and excellent magneto-thermal performance. MHT, which is realized by Fe3O4@Gel subjected to an alternating magnetic field, leads to reduced lipid accumulation, lower triglyceride content, and increased mitochondrial activity in white adipocytes. This work shows that Fe3O4@Gel-mediated MHT can effectively promote lipolysis in white adipocytesin vitro, which provides a potential approach to treat obesity and associated metabolic disorders.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipertermia Inducida , Humanos , Lipólisis , Adipocitos Blancos , Microesferas , Hidrogeles , Obesidad , Lípidos , Hipertermia Inducida/métodos , Fenómenos Magnéticos
7.
Mikrochim Acta ; 191(1): 34, 2023 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-38108923

RESUMEN

Magnetic solid phase extraction with the functionalization of protein onto micro- or nano-particles as a probe is favorable for the discovery of new drugs from complicated natural products. Herein, we aimed to develop a rapid method by immobilizing halogenated alkane dehalogenase (Halo)-tagged calcium-sensing receptor (CaSR) directly out of crude cell lysates onto the surface of magnetic microspheres (MM) with no need to purify protein. Thereby we achieved CaSR-functionalized MM for revealing adsorption characteristics of agonist neomycin and screening ligands from herbal medicine Radix Astragali (RA). About 43.87 mg CaSR could be immobilized per 1 g MM within 30 min, and the acquired CaSR-functionalized MM showed good stability and activity for 4 weeks. The maximum adsorption capacity of neomycin on CaSR-functionalized MM was determined as 4.70 × 10-4 ~ 3.96 × 10-4 mol/g within 277 ~ 310 K, and its adsorption isotherm characteristics described best by the Temkin model were further validated using isothermal titration calorimetry. It was inferred that CaSR's affinity for neomycin was driven by electrostatic forces in a spontaneous process when the system reached an equilibrium state. Moreover, the ligands from the RA extract were screened, three of which were assigned as astragaloside IV, ononin, and calycosin based on HPLC-MS. Our findings demonstrated that the functionalization of a receptor onto magnetic materials designed as an affinity probe has the capability to recognize its agonist and capture the ligands selectively from complex matrices like herbs.


Asunto(s)
Neomicina , Receptores Sensibles al Calcio , Microesferas , Adsorción , Ligandos , Fenómenos Magnéticos
8.
Int J Biol Macromol ; 253(Pt 7): 127480, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37863144

RESUMEN

The use of targeted chemotherapy is a promising solution to mitigate the side effects and dosage of drugs. This research focuses on the development of magnetic microspheres (MMS) based drug carriers for targeted chemotherapy, formulated with iron oxide nanoparticles (Fe3O4 NPs) and poly (l-lactic acid) (PLA) loaded with the antibiotic drug Ciprofloxacin (CIF). In this study, Fe3O4 NPs were synthesized using pomegranate peel extract as a natural reducing and stabilizing agent. The double emulsification method (W1/O/W2) was employed to produce Fe3O4@LEC-CIF-PLA-MMS, which were characterized using various spectral and microscopic techniques. The drug encapsulation efficiency for Fe3O4@LEC-CIF-PLA-MMS was found to be 80.7 %. The in vitro drug release of CIF from Fe3O4@LEC-CIF-PLA-MMS induced by H2O2 and GSH- stimuli was found to be 87.55 % and 82.32 %, respectively in acidic pH 4.5. Notably, the magnetically triggered drug release behaviour of Fe3O4@LEC-CIF-PLA-MMS (93.56 %) was assessed in acidic pH environment upon exposure to low-frequency alternating magnetic field (LF-AMF). Fe3O4@LEC-CIF-PLA-MMS demonstrated significantly enhanced in vitro cytotoxicity (IC50 = 0.8 ± 0.03 µg/mL) against the HeLa-S3 cancer cell lines. Nevertheless, these research findings highlight the potential of Fe3O4@LEC-CIF-PLA-MMS for further development as a chemotherapeutic agent and hold promise for the future of targeted cancer treatment.


Asunto(s)
Lecitinas , Neoplasias , Liberación de Fármacos , Microesferas , Peróxido de Hidrógeno , Poliésteres/química , Portadores de Fármacos/química , Nanopartículas Magnéticas de Óxido de Hierro , Ácido Láctico/química
9.
Trends Mol Med ; 29(12): 976-978, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37863716

RESUMEN

Yang et al. recently demonstrated the high potential of liquid metal microspheres (LM MSs) in cancer therapy. By amplifying the effects of magnetic hyperthermia and embolization, LM MSs not only target primary tumors, but also potentiate immune defenses. This dual-action approach effectively curtails distant tumor growth, marking a pivotal advancement in cancer immunotherapy.


Asunto(s)
Embolización Terapéutica , Hipertermia Inducida , Neoplasias , Humanos , Neoplasias/terapia , Inmunoterapia , Terapia Combinada
10.
Biosystems ; 232: 105015, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37657746

RESUMEN

Proteinoids, or thermal proteins, are produced by heating amino acids to their melting point and initiating polymerisation to produce polymeric chains. In aqueous solutions proteinoids swell into hollow microspheres. These microspheres produce endogenous burst of electrical potential spikes and change patterns of their electrical activity in response to illumination. We report results on a detailed investigation on the effects of white cold light on the spiking of proteinoids. We study how different types and intensities of light determine proteinoids' spiking amplitude, period, and pattern. The results of this study will be utilised to evaluate proteinoids for their potential as optical sensors and their application in unconventional computing.


Asunto(s)
Aminoácidos , Luz , Microesferas , Polimerizacion
11.
Int J Biol Macromol ; 247: 125831, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37454998

RESUMEN

From a practical standpoint, it is still challenging to develop adsorbents with high adsorption capacity and outstanding selectivity for rhenium in uranium ore leaching solution. In this study, in order to explore the structure-property relationship, four nucleobases (Adenine, Guanine, Hypoxanthine and Xanthine) were used as functionalization reagents to modify cellulose (MCC-g-GMA-A, MCC-g-GMA-G, MCC-g-GMA-H and MCC-g-GMA-X) via radiation method. The effect of the type of nucleobases on the adsorption performance was evaluated by batch and dynamic experiments. The order of maximum adsorption capacity was MCC-g-GMA-A (194.0 mg g-1) > MCC-g-GMA-G (123.4 mg g-1) > MCC-g-GMA-H (45.59 mg g-1) > MCC-g-GMA-X (23.43 mg g-1), which was associated with the category of nitrogen-functional groups. Different nitrogen-containing functional groups have different degrees of protonation, which leads to differences in the interaction of the adsorbent with Re(VII). Notably, the adsorbents were able to selectively capture trace Re(VII) from the simulated uranium ore leaching solution. The FT-IR, XPS analyses, DFT theoretical calculations exhibited that the adsorption mechanism of nucleobases functionalized cellulose microspheres and Re(VII) was electrostatic interaction. MCC-g-GMA-A and MCC-g-GMA-G exhibited excellent selectivity towards Re(VII), which are potential adsorbents for Re(VII) recovery in uranium ore leaching solutions.


Asunto(s)
Celulosa , Uranio , Espectroscopía Infrarroja por Transformada de Fourier , Microesferas , Adsorción
12.
Polymers (Basel) ; 15(11)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37299231

RESUMEN

In recent years, composite biomaterials have attracted attention for drug delivery applications due to the possibility of combining desired properties of their components. However, some functional characteristics, such as their drug release efficiency and likely side effects, are still unexplored. In this regard, controlled tuning of the drug release kinetic via the precise design of a composite particle system is still of high importance for many biomedical applications. This objective can be properly fulfilled through the combination of different biomaterials with unequal release rates, such as mesoporous bioactive glass nanoparticles (MBGN) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) microspheres. In this work, MBGNs and PHBV-MBGN microspheres, both loaded with Astaxanthin (ASX), were synthesised and compared in terms of ASX release kinetic, ASX entrapment efficiency, and cell viability. Moreover, the correlation of the release kinetic to phytotherapeutic efficiency and side effects was established. Interestingly, there were significant differences between the ASX release kinetic of the developed systems, and cell viability differed accordingly after 72 h. Both particle carriers effectively delivered ASX, though the composite microspheres exhibited a more prolonged release profile with sustained cytocompatibility. The release behaviour could be fine-tuned by adjusting the MBGN content in the composite particles. Comparatively, the composite particles induced a different release effect, implying their potential for sustained drug delivery applications.

13.
Eur J Pharm Biopharm ; 189: 98-108, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37330116

RESUMEN

Transcatheter arterial embolization (TAE) has played a huge role in the interventional treatment of organ bleeding and accidental bleeding. Choosing bio-embolization materials with good biocompatibility is an important part of TAE. In this work, we prepared a calcium alginate embolic microsphere using high-voltage electrostatic droplet technology. The microsphere simultaneously encapsulated silver sulfide quantum dots (Ag2S QDs) and barium sulfate (BaSO4), and fixed thrombin on its surface. Thrombin can achieve an embolic effect while stopping bleeding. The embolic microsphere has good near-infrared two-zone (NIR-II) imaging and X-ray imaging effects, and the luminous effect of NIR-II is better than that of X-rays. This breaks the limitations of traditional embolic microspheres that only have X-ray imaging. And the microspheres have good biocompatibility and blood compatibility. Preliminary application results show that the microspheres can achieve a good embolization effect in the ear arteries of New Zealand white rabbits, and can be used as an effective material for arterial embolization and hemostasis. This work realizes the clinical embolization application of NIR-II combined with X-ray multimodal imaging technology in biomedical imaging, achieving complementary advantages and excellent results, more suitable for studying biological changes and clinical applications.


Asunto(s)
Embolización Terapéutica , Trombina , Animales , Conejos , Microesferas , Alginatos , Embolización Terapéutica/métodos
14.
J Med Econ ; 26(1): 731-741, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37139828

RESUMEN

AIMS: Hepatocellular carcinoma (HCC) is a severe condition with poor prognosis that places a significant burden on patients, caregivers, and healthcare systems. Selective internal radiation therapy (SIRT) is a treatment available to patients with HCC which addresses some of the limitations of alternative treatment options. A cost-effectiveness analysis was undertaken into the use of SIRT using Y-90 resin microspheres for the treatment of unresectable intermediate- and late-stage HCC in Brazil. MATERIALS AND METHODS: A partitioned-survival model was developed, including a tunnel state for patients downstaged to receive treatments with curative intent. Sorafenib was the selected comparator, a common systemic treatment in Brazil and for which comparative evidence exists. Clinical data were extracted from published sources of pivotal trials, and effectiveness was measured in quality-adjusted life-years (QALYs) and life-years (LYs). The analysis was conducted from the Brazilian private payer perspective and a lifetime horizon was implemented. Comprehensive sensitivity analyses were conducted. RESULTS: LYs and QALYs were higher for SIRT with Y-90 resin microspheres versus sorafenib (0.27 and 0.20 incremental LYs and QALYs, respectively) and costs were slightly higher for SIRT (R$15,864). The base case incremental cost-effectiveness ratio (ICER) was R$77,602 per QALY. The ICER was mostly influenced by parameters defining the sorafenib overall survival curve and SIRT had a 73% probability of being cost-effective at a willingness-to-pay threshold of R$135,761 per QALY (3-times the per-capita gross domestic product in Brazil). Overall, sensitivity analyses confirmed the robustness of the results indicating that SIRT with Y-90 resin microspheres is cost-effective compared with sorafenib. LIMITATIONS: A rapidly evolving treatment landscape in Brazil and worldwide, and the lack of local data for some variables were the main limitations. CONCLUSIONS: SIRT with Y-90 resin microspheres is a cost-effective option compared with sorafenib in Brazil.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Sorafenib/uso terapéutico , Análisis Costo-Beneficio , Radioisótopos de Itrio , Brasil , Neoplasias Hepáticas/tratamiento farmacológico , Microesferas
15.
Biosystems ; 227-228: 104892, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37076037

RESUMEN

Proteinoids, or thermal proteins, are inorganic entities formed by heating amino acids to their melting point and commencing polymerisation to form polymeric chains. Typically, their diameters range from 1µm to 10µm. Some amino acids incorporated into proteinoid chains are more hydrophobic than others, leading proteinoids to cluster together when they are present in aqueous solutions at specific concentrations, allowing them to grow into microspheres. The peculiar structure of proteinoids composed of linked amino acids endows them with unique properties, including action-potential like spiking of electrical potential. These unique properties make ensembles of proteinoid microspheres a promising substrate for designing future artificial brains and unconventional computing devices. To evaluate a potential of proteinoid microspheres for unconventional electronic devices we measure and analyse the data-transfer capacities of proteinoid microspheres. In experimental laboratory conditions we demonstrate that the transfer function of proteinoids microspheres is a nontrivial phenomenon, which might be due to the wide range of proteinoid shapes, sizes, and structures.


Asunto(s)
Aminoácidos , Proteínas , Microesferas , Proteínas/metabolismo
16.
Int J Biol Macromol ; 237: 123982, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36907297

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged since the early 1960s. The increasing resistance of pathogens to currently used antibiotics requires the urgent discovery of new antimicrobials effective in combating drug-resistant bacteria. From past to present, medicinal plants are useful to cure human diseases. Corilagin (ß-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-d-glucose), commonly found in Phyllanthus species, exerts potentiating effect on ß-lactams against MRSA. However, its biological effect may not be fully utilized. Therefore, incorporating microencapsulation technology with the delivery of corilagin would be more effective in utilizing the potential effect on biomedical applications. This work reports the development of a safe micro-particulate system which combined agar with gelatin as wall matrix materials for topical delivery of corilagin in order to eliminate the potential toxicity of the crosslinker formaldehyde. The optimal parameters for microsphere preparation were identified and the particle size of optimal microspheres was 20.11 µm ± 3.58. Antibacterial studies revealed that micro-trapped corilagin (minimum bactericidal concentration, MBC = 0.5 mg/mL) possessed a higher potency against MRSA than free corilagin (MBC = 1 mg/mL). The in vitro skin cytotoxicity showed the safety of the corilagin-loaded microspheres for topical applications, with approximately 90 % of HaCaT cell viability. Our results demonstrated the potential of corilagin-loaded gelatin/agar microspheres for the applicable bio-textile products to treat drug-resistant bacterial infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Humanos , Staphylococcus aureus , Gelatina/farmacología , Agar/farmacología , Microesferas , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología
17.
Sensors (Basel) ; 23(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36679729

RESUMEN

Stable, water-soluble titanium complexed with mandelic acid was used as a precursor for titanium phosphorus double oxide obtained in hydrothermal conditions in the presence of phosphoric acid. Surprisingly, hydrolysis of organic complexes provided a microstructured sphere with narrow size distribution, low aggregation and a small fraction of morphological irregularities. Obtained microspheres had a complex structure comprised of flakes, whose size could be manipulated with temperature conditions. Samples were found to be electrochemically active against sulcotrione, a well-recognized herbicide. Electrochemical sensors based on the synthesized microspheres were successfully adapted for natural water reservoir analysis and exhibited low levels of detection of 0.61 µM, limit of quantification of 1.86 µM, wide dynamic linear range from 2 to 200 µM, good selectivity, excellent reproducibility and in-time stability.


Asunto(s)
Fósforo , Titanio , Titanio/química , Reproducibilidad de los Resultados , Óxidos/química , Agua
18.
Anal Bioanal Chem ; 415(7): 1371-1383, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36651973

RESUMEN

In this study, a novel cell membrane chromatography (CMC) model was developed to investigate cluster of differentiation 147 (CD147) targeted anti-tumor drug leads for specific screening and ligand-receptor interaction analysis by SNAP-tagged CD147 fusion protein conjugation and polystyrene microspheres (PS) modification. Traditional Chinese medicines (TCMs) are widely used in the treatment of cancer. CD147 plays important roles in tumor progression and acts as an attractive target for therapeutic intervention; therapeutic drugs for CD147-related cancers are limited to date. Thus, a screening method for active components in TCMs is crucial for the further research and development of CD147 antagonists. However, improvement is still needed to perform specific and accurate drug lead screening using the CMC-based method. Recently, our group developed a covalently immobilized receptor-SNAP-tag/CMC model using silica gel as carrier. Besides the carboxyl group on multi-step modified silica particles, the amino group of benzyl-guanine (BG, substrate of SNAP-tag) also possesses reactivity towards the carboxyl group on available carboxyl-modified PS. Herein, we used PS as carrier and an extended SNAP-tag with CD147 receptor to construct the PS-BG-CD147/CMC model for active compound investigation coupled with HPLC/MS and applied this coupled PS-BG-CD147/CMC-HPLC/MS two-dimensional system to drug lead screening from Nelumbinis Plumula extract (NPE) sample. In addition, to comprehensively verify the pharmacological effects of screened ingredients, a cell proliferation inhibition assay was performed, and the interaction between the ingredients and CD147 was studied by the frontal analysis method. This study developed a high-throughput PS-based CMC screening platform, which could be widely applied and utilized in chromatographic separation and drug lead discovery.


Asunto(s)
Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/química , Poliestirenos/análisis , Microesferas , Cromatografía Líquida de Alta Presión/métodos , Membrana Celular/química
19.
Adv Healthc Mater ; 12(14): e2201581, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36495232

RESUMEN

To streamline the drug discovery pipeline, there is a pressing need for preclinical models which replicate the complexity and scale of native tumors. While there have been advancements in the formation of microscale tumor units, these models are cell-line dependent, time-consuming and have not improved clinical trial success rates. In this study, two methods for generating 3D tumor microenvironments are compared, rapidly fabricated hydrogel microspheres and traditional cell-dense spheroids. These modules are then bioassembled into 3D printed thermoplastic scaffolds, using an automated biofabrication process, to form tumor-scale models. Modules are formed with SKOV3 and HFF cells as monocultures and cocultures, and the fabrication efficiency, cell architecture, and drug response profiles are characterized, both as single modules and as multimodular constructs. Cell-encapsulated Gel-MA microspheres are fabricated with high-reproducibility and dimensions necessary for automated tumor-scale bioassembly regardless of cell type, however, only cocultured spheroids form compact modules suitable for bioassembly. Chemosensitivity assays demonstrate the reduced potency of doxorubicin in coculture bioassembled constructs and a ≈five-fold increase in drug resistance of cocultured cells in 3D modules compared with 2D monolayers. This bioassembly system is efficient and tailorable so that a variety of relevant-sized tumor constructs could be developed to study tumorigenesis and modernize drug discovery.


Asunto(s)
Esferoides Celulares , Microambiente Tumoral , Evaluación Preclínica de Medicamentos , Reproducibilidad de los Resultados , Técnicas de Cocultivo
20.
Am J Transl Res ; 14(10): 7135-7146, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36398211

RESUMEN

Doxorubicin loaded DC beads (microspheres) has been used for treating un-resectable tumours by transarterial chemoembolization (TACE). We have shown that bromelain, an enzyme from the pineapple plant, enhances the cytotoxic effect of a number of chemotherapeutic drugs and in an earlier study we have demonstrated that it can be loaded into DC beads. Therefore, in the current study we have investigated how certain physical and chemical parameters affect its loading and release for future development of DC beads in cancer therapy. Aliquots of 40-60 µL of DC beads (100-300 µm) were treated to bromelain in distilled water and various parameters such as pH of solution, bromelain concentration, temperature, loading period, presence/absence of agitation and the cytotoxic effect of bromelain loaded beads were investigated. Further release kinetics was also studied with additional investigation of pH effect on the proteolytic activity of bromelain. Results indicate that higher loading of bromelin was achieved in the beads at lower pH, higher concentration of bromelain, with agitation, 24 hours loading and ambient room temperature. Proteolytic activity of bromelain was maximal at pH 4.5 whilst cytotoxicity was at par if not better in the bromelain loaded DC beads. Release kinetics indicated that bromelain can be delivered over several hours. Hence, we conclude that bromelain can be loaded more efficiently with manipulation of certain parameters with noticeable cytotoxicity in tumour cells.

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