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1.
Mikrochim Acta ; 191(5): 260, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607575

RESUMO

Isoniazid and streptomycin are vital drugs for treating tuberculosis, which are utilized as efficient anti-tuberculosis agents. This paper presents a novel visible-light-driven composite photocatalyst Ti3C2/Bi/BiOI, which was built from Ti3C2 nanosheets and Bi/BiOI microspheres. Photoelectrochemical (PEC) sensors based on Ti3C2/Bi/BiOI were synthesized for isoniazid identification, which showed a linear concentration range of 0.1-125 µM with a detection limit of 0.05 µM (S/N = 3). Moreover, we designed a PEC aptasensors based on aptamer/Ti3C2/Bi/BiOI to detect streptomycin in 0.1 M PBS covering the electron donor isoniazid, because the isoniazid consumes photogenerated holes thus increasing the photocurrent effectively and preventing photogenerated electron-hole pairs from being recombined. Furthermore, PEC aptasensors based on aptamer/Ti3C2/Bi/BiOI were synthesized for streptomycin identification, which exhibited a linear concentration range of 0.01-1000 nM with a detection limit of 2.3 × 10-3 nM (S/N = 3), and are well stable in streptomycin sensing.


Assuntos
Isoniazida , Estreptomicina , Microesferas , Titânio , Livros , Metais , Oligonucleotídeos
2.
J Biomed Opt ; 29(4): 046501, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38629030

RESUMO

Significance: Light-sheet fluorescence microscopy (LSFM) has emerged as a powerful and versatile imaging technique renowned for its remarkable features, including high-speed 3D tomography, minimal photobleaching, and low phototoxicity. The interference light-sheet fluorescence microscope, with its larger field of view (FOV) and more uniform axial resolution, possesses significant potential for a wide range of applications in biology and medicine. Aim: The aim of this study is to investigate the interference behavior among multiple light sheets (LSs) in LSFM and optimize the FOV and resolution of the light-sheet fluorescence microscope. Approach: We conducted a detailed investigation of the interference effects among LSs through theoretical derivation and numerical simulations, aiming to find optimal parameters. Subsequently, we constructed a customized system of multi-LSFM that incorporates both interference light sheets (ILS) and noninterference light-sheet configurations. We performed beam imaging and microsphere imaging tests to evaluate the FOV and axial resolution of these systems. Results: Using our custom-designed light-sheet fluorescence microscope, we captured the intensity distribution profiles of both interference and noninterference light sheets (NILS). Additionally, we conducted imaging tests on microspheres to assess their imaging outcomes. The ILS not only exhibits a larger FOV compared to the NILS but also demonstrates a more uniform axial resolution. Conclusions: By effectively modulating the interference among multiple LSs, it is possible to optimize the intensity distribution of the LSs, expand the FOV, and achieve a more uniform axial resolution.


Assuntos
Microscopia de Fluorescência , Microscopia de Fluorescência/métodos , Microesferas , Fotodegradação
3.
Environ Health Perspect ; 132(4): 47005, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598326

RESUMO

BACKGROUND: Global plastic use has consistently increased over the past century with several different types of plastics now being produced. Much of these plastics end up in oceans or landfills leading to a substantial accumulation of plastics in the environment. Plastic debris slowly degrades into microplastics (MPs) that can ultimately be inhaled or ingested by both animals and humans. A growing body of evidence indicates that MPs can cross the gut barrier and enter into the lymphatic and systemic circulation leading to accumulation in tissues such as the lungs, liver, kidney, and brain. The impacts of mixed MPs exposure on tissue function through metabolism remains largely unexplored. OBJECTIVES: This study aims to investigate the impacts of polymer microspheres on tissue metabolism in mice by assessing the microspheres ability to translocate across the gut barrier and enter into systemic circulation. Specifically, we wanted to examine microsphere accumulation in different organ systems, identify concentration-dependent metabolic changes, and evaluate the effects of mixed microsphere exposures on health outcomes. METHODS: To investigate the impact of ingested microspheres on target metabolic pathways, mice were exposed to either polystyrene (5µm) microspheres or a mixture of polymer microspheres consisting of polystyrene (5µm), polyethylene (1-4µm), and the biodegradability and biocompatible plastic, poly-(lactic-co-glycolic acid) (5µm). Exposures were performed twice a week for 4 weeks at a concentration of either 0, 2, or 4mg/week via oral gastric gavage. Tissues were collected to examine microsphere ingress and changes in metabolites. RESULTS: In mice that ingested microspheres, we detected polystyrene microspheres in distant tissues including the brain, liver, and kidney. Additionally, we report on the metabolic differences that occurred in the colon, liver, and brain, which showed differential responses that were dependent on concentration and type of microsphere exposure. DISCUSSION: This study uses a mouse model to provide critical insight into the potential health implications of the pervasive issue of plastic pollution. These findings demonstrate that orally consumed polystyrene or mixed polymer microspheres can accumulate in tissues such as the brain, liver, and kidney. Furthermore, this study highlights concentration-dependent and polymer type-specific metabolic changes in the colon, liver, and brain after plastic microsphere exposure. These results underline the mobility within and between biological tissues of MPs after exposure and emphasize the importance of understanding their metabolic impact. https://doi.org/10.1289/EHP13435.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Humanos , Animais , Camundongos , Microesferas , Plásticos , Distribuição Tecidual , Microplásticos , Poluentes Químicos da Água/análise
4.
Mikrochim Acta ; 191(5): 251, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38589663

RESUMO

Nanocomposite microbeads (average diameter = 10-100 µm) were prepared by a microemulsion-solidification method and applied to the magnetic solid-phase extraction (m-SPE) of fourteen analytes, among pesticides, drugs, and hormones, from human urine samples. The microbeads, perfectly spherical in shape to maximize the surface contact with the analytes, were composed of magnetic nanoparticles dispersed in a polylactic acid (PLA) solid bulk, decorated with multi-walled carbon nanotubes (mPLA@MWCNTs). In particular, PLA was recovered from filters of smoked electronic cigarettes after an adequate cleaning protocol. A complete morphological characterization of the microbeads was performed via Fourier-transform infrared (FTIR) spectroscopy, UV-Vis spectroscopy, thermogravimetric and differential scanning calorimetry analysis (TGA and DSC), scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). The recovery study of the m-SPE procedure showed yields ≥ 64%, with the exception of 4-chloro-2-methylphenol (57%) at the lowest spike level (3 µg L-1). The method was validated according to the main FDA guidelines for the validation of bioanalytical methods. Using liquid chromatography-tandem mass spectrometry, precision and accuracy were below 11% and 15%, respectively, and detection limits of 0.1-1.8 µg L-1. Linearity was studied in the range of interest 1-15 µg L-1 with determination coefficients greater than 0.99. In light of the obtained results, the nanocomposite microbeads have proved to be a valid and sustainable alternative to traditional sorbents, offering good analytical standards and being synthetized from recycled plastic material. One of the main objectives of the current work is to provide an innovative and optimized procedure for the recycling of a plastic waste, to obtain a regular and reliable microstructure, whose application is here presented in the field of analytical chemistry. The simplicity and greenness of the method endows the procedure with a versatile applicability in different research and industrial fields.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Nanocompostos , Nanotubos de Carbono , Humanos , Nanotubos de Carbono/química , Xenobióticos , Microesferas , Poliésteres , Extração em Fase Sólida/métodos , Nanocompostos/química , Fenômenos Magnéticos
5.
ACS Appl Bio Mater ; 7(4): 2554-2568, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38574371

RESUMO

Multidrug-resistant bacteria are a serious problem in biomedical applications that decrease the wound healing process and increase the mortality rate. Therefore, in this study, we have prepared a green-synthesized silver-nanoparticle-encapsulated mucilage microsphere (HMMS@GSNP) from Hibiscus rosa sinensis leaves and applied it to pathogen-infected burn and excision wounds. Biophysical properties like size, polydispersity index, absorbance capacity, and drug release were measured by different techniques like field-emission scanning electron microscopy, dynamic light scattering, swelling ratio, etc. The strong antibacterial activity of a HMMS@GSNP microsphere was measured by minimum inhibitory concentration assay, minimum bactericidal concentration assay, and agar well diffusion methods. The HMMS@GSNP microsphere enhanced the cell viability, cell proliferation, migration, antioxidant, and antiinflammation activity compared to untreated GSNP and HMMS, as quantified by MTT assay, BrdU assay, scratch wound assay, reactive oxygen species scavenging assay, and Western blot analysis, respectively. In the in vivo experiment, we used a methicillin-resistant Staphylococcus aureus bacteria-infected, burn-and-excision-wound-created male BALB/c mice model. The HMMS@GSNP-treated burn-and-excision-wound-infected mice showed significant results compared to other groups (untreated, Silverex Ionic Gel, AgNO3, HMMS, and GSNP), and the mice tissues were utilized for bacteria count, immunoblot analysis, histological studies, and real-time polymerase chain reaction. Thus, the HMM@GSNP microsphere is an excellent therapeutic material that can be used as a topical agent for the management of chronic wound therapy.


Assuntos
Queimaduras , Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Masculino , Camundongos , Animais , Prata , Microesferas , Queimaduras/tratamento farmacológico
6.
Molecules ; 29(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611935

RESUMO

Immobilized metal ion affinity chromatography (IMAC) adsorbents generally have excellent affinity for histidine-rich proteins. However, the leaching of metal ions from the adsorbent usually affects its adsorption performance, which greatly affects the reusable performance of the adsorbent, resulting in many limitations in practical applications. Herein, a novel IMAC adsorbent, i.e., Cu(II)-loaded polydopamine-coated urchin-like titanate microspheres (Cu-PDA-UTMS), was prepared via metal coordination to make Cu ions uniformly decorate polydopamine-coated titanate microspheres. The as-synthesized microspheres exhibit an urchin-like structure, providing more binding sites for hemoglobin. Cu-PDA-UTMS exhibit favorable selectivity for hemoglobin adsorption and have a desirable adsorption capacity towards hemoglobin up to 2704.6 mg g-1. Using 0.1% CTAB as eluent, the adsorbed hemoglobin was easily eluted with a recovery rate of 86.8%. In addition, Cu-PDA-UTMS shows good reusability up to six cycles. In the end, the adsorption properties by Cu-PDA-UTMS towards hemoglobin from human blood samples were analyzed by SDS-PAGE. The results showed that Cu-PDA-UTMS are a high-performance IMAC adsorbent for hemoglobin separation, which provides a new method for the effective separation and purification of hemoglobin from complex biological samples.


Assuntos
Hemoglobinas , Imidazóis , Indóis , Polímeros , Humanos , Microesferas , Cromatografia de Afinidade , Íons
7.
Appl Microbiol Biotechnol ; 108(1): 283, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573435

RESUMO

Porcine reproductive and respiratory syndrome (PRRS) is an immunosuppressive disease caused by the porcine reproductive and respiratory syndrome virus (PRRSV). Current vaccine prevention and treatment approaches for PRRS are not adequate, and commercial vaccines do not provide sufficient cross-immune protection. Therefore, establishing a precise, sensitive, simple, and rapid serological diagnostic approach for detecting PRRSV antibodies is crucial. The present study used quantum dot fluorescent microspheres (QDFM) as tracers, covalently linked to the PRRSV N protein, to develop an immunochromatography strip (ICS) for detecting PRRSV antibodies. Monoclonal antibodies against PRRSV nucleocapsid (N) and membrane (M) proteins were both coated on nitrocellulose membranes as control (C) and test (T) lines, respectively. QDFM ICS identified PRRSV antibodies under 10 min with high sensitivity and specificity. The specificity assay revealed no cross-reactivity with the other tested viruses. The sensitivity assay revealed that the minimum detection limit was 1.2 ng/mL when the maximum dilution was 1:2,048, comparable to the sensitivity of enzyme-linked immunosorbent assay (ELISA) kits. Moreover, compared to PRRSV ELISA antibody detection kits, the sensitivity, specificity, and accuracy of QDFM ICS after analyzing 189 clinical samples were 96.7%, 97.9%, and 97.4%, respectively. Notably, the test strips can be stored for up to 6 months at 4 °C and up to 4 months at room temperature (18-25 °C). In conclusion, QDFM ICS offers the advantages of rapid detection time, high specificity and sensitivity, and affordability, indicating its potential for on-site PRRS screening. KEY POINTS: • QDFM ICS is a novel method for on-site and in-lab detection of PRRSV antibodies • Its sensitivity, specificity, and accuracy are on par with commercial ELISA kits • QDFM ICS rapidly identifies PRRSV, aiding the swine industry address the evolving virus.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Pontos Quânticos , Animais , Suínos , Microesferas , Síndrome Respiratória e Reprodutiva Suína/diagnóstico , Corantes , Anticorpos Antivirais , Cromatografia de Afinidade
8.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474598

RESUMO

Single-particle inductively coupled plasma mass spectrometry (spICP-MS) has been used for particle size measurement of diverse types of individual nanoparticles and micrometer-sized carbon-based particles such as microplastics. However, its applicability to the measurement of micrometer-sized non-carbon-based particles such as silica (SiO2) particles is unclear. In this study, the applicability of spICP-MS to particle size measurement of non-porous/mesoporous SiO2 microspheres with a nominal diameter of 5.0 µm or smaller was investigated. Particle sizes of these microspheres were measured using both spICP-MS based on a conventional calibration approach using an ion standard solution and scanning electron microscopy as a reference technique, and the results were compared. The particle size distributions obtained using both techniques were in agreement within analytical uncertainty. The applicability of this technique to the detection of metal-containing protein-binding mesoporous SiO2 microspheres was also investigated. Bound iron (Fe)-containing proteins (i.e., lactoferrin and transferrin) of mesoporous SiO2 microspheres were detected using Fe as a presence marker for the proteins. Thus, spICP-MS is applicable to the particle size measurement of large-sized and non-porous/mesoporous SiO2 microspheres. It has considerable potential for element-based detection and qualification of bound proteins of mesoporous SiO2 microspheres in a variety of applications.


Assuntos
Plásticos , Dióxido de Silício , Dióxido de Silício/química , Tamanho da Partícula , Microesferas , Espectrometria de Massas/métodos
9.
Int J Biol Macromol ; 264(Pt 1): 130575, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432270

RESUMO

Hydroxypropyl guar gum (HPG) is a critical thickener to increase viscosity and lubrication to improve the water-based hydraulic fracturing efficiency. However, current crosslinkers require a large amount of HPG (>0.3 wt%) to form gel with sufficient viscosity, and high concentrations of HPG may cause adverse effects to the production and the environment. In this study, a novel starch microsphere silica­boron crosslinker (SMSB) was developed using starch microspheres as a carrier and γ-aminopropyl triethoxy silane (KH550) as a modifier with an in-house method. Both the rheology and surface reactions of the SMSB-HPG crosslinking system were studied using multiple laboratory experiments and molecular dynamics simulation. The results showed that SMSB crosslinker caused multi-site cross-linking with low concentration (only 0.2 wt%) of HPG molecules, reducing the twisting of single molecular chain in the crosslinking system, enhancing the cross-linking strength between molecular chains, and making HPG molecular chains stretcher in the aqueous solution. The apparent viscosity and viscoelasticity of the HPG system were substantially higher than the organoboron crosslinker, and the temperature resistance of the SMSB-HPG crosslinking system was up to 140 °C. This study provides an alternative green crosslinker for more sustainable industrial applications and provides theoretical basis for the modification of biomaterials.


Assuntos
Boro , Polissacarídeos , Amido , Silício , Microesferas , Galactanos , Mananas , Gomas Vegetais , Água
10.
Int J Biol Macromol ; 265(Pt 2): 130898, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508556

RESUMO

Anti-infection hydrogels have recently aroused enormous attraction, particularly in the treatment of chronic wounds. Herein, silver nanoparticle@catechol formaldehyde resin microspheres (Ag@CFRs) were fabricated by one-step hydrothermal method and subsequently encapsulated in hydrogels which were developed by Schiff base reaction between aldehyde groups in oxidized hyaluronic acid and amino groups in carboxymethyl chitosan. The developed polysaccharide hydrogel exhibited microporous structure, high swelling capacity, favorable mechanical strength, enhanced tissue adhesion and photothermal activities. Additionally, the hydrogel not only ensured long-term and high-efficiency antibacterial performance (99.9 %) toward E. coli and S. aureus, but also realized superior cytocompatibility in vitro. Moreover, based on the triple antibacterial strategies endowed by chitosan, silver nanoparticles and the photothermal properties of catechol microspheres, the composite hydrogel exhibited excellent anti-infection function, significantly downregulated inflammatory factors (TNF-α and IL-1ß) and promoted in vivo infected-wound healing. These results demonstrated that the polysaccharide hydrogel containing Ag@CFRs has great potential for infected-wounds repair.


Assuntos
Quitosana , Nanopartículas Metálicas , Hidrogéis/farmacologia , Prata , Escherichia coli , Microesferas , Staphylococcus aureus , Antibacterianos/farmacologia , Catecóis/farmacologia , Anti-Inflamatórios , Polissacarídeos/farmacologia
11.
Int J Biol Macromol ; 265(Pt 2): 131059, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38521338

RESUMO

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.


Assuntos
Matriz Óssea , Osteogênese , Camundongos , Animais , Humanos , Microesferas , Fósforo , Regeneração Óssea , Alginatos/farmacologia , Alginatos/química
12.
Chemosphere ; 355: 141776, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522667

RESUMO

The efficient removal of phosphate from water environments was extremely significant to control eutrophication of water bodies and prevent further deterioration of water quality. In this study, oxygen vacancy-rich magnesium oxide (OV-MgO) microspheres were synthesized by a simple solvothermal method coupling high-temperature calcination. The effects of adsorbent dosage, contact time, initial pH and coexisting components on phosphate adsorption performance were examined. The physicochemical properties of OV-MgO microspheres and the phosphate removal mechanisms were analyzed by various characterization techniques. The maximum adsorption capacity predicted by the Sips isotherm model was 379.7 mg P/g for OV-MgO microspheres. The phosphate adsorption in this study had a fast adsorption kinetics and a high selectivity. OV-MgO microspheres had a good acid resistance for phosphate adsorption, but their adsorption capacity decreased under alkaline conditions. The electrostatic attraction, ligand exchange, surface precipitation, inner-sphere surface complexation and oxygen vacancy capture were mainly responsible for efficient removal of phosphate from aqueous solutions. This study probably promoted the development of oxygen vacancy-rich metal (hydr)oxides with potential application prospects.


Assuntos
Fosfatos , Poluentes Químicos da Água , Fosfatos/química , Óxido de Magnésio/química , Microesferas , Poluentes Químicos da Água/análise , Cinética , Adsorção
13.
Int J Biol Macromol ; 265(Pt 1): 130897, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490376

RESUMO

Although iron in meat is an important trace element for human diet, its presence also induces postprandial oxidative stress and aggravates the condition of patients with iron overload. To overcome this situation, a type of new tunable Fe-absorption bioactive materials was constructed in this study. First, four phenolic acids (Caffeic acid, Gallic acid, Protocatechuic acid, Chlorogenic acid) were grafted onto chitosan. Then, the copolymers were prepared into micron-level microspheres by emulsification method, which were characterized in adsorption isotherms (Langmuir model), swelling behavior and digestion characteristics. In order to verify the practical application effect of microspheres, Protocatechuic acid grafted chitosan microspheres as the representative were used in sirloin powder to observe their effects in vitro digestion and rat experiment. In the present study, microspheres were innovatively applied in meat consumption, which significantly inhibited the oxidation of meat in the process of digestion and effectively controlled the iron absorption. These results are expected to play an important role in promoting the healthy consumption of meat around the world, improving gastrointestinal redox status through dietary assistance, and treating diseases related to iron overload.


Assuntos
Quitosana , Hidroxibenzoatos , Sobrecarga de Ferro , Humanos , Ratos , Animais , Microesferas , Oxirredução , Carne , Ferro , Digestão
14.
Langmuir ; 40(13): 6971-6979, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38517386

RESUMO

The development of fluorescently labeled microspheres is a critical aspect of advancing the technology of lateral flow immunochromatography (LFIA) for biological detection. Nevertheless, potential interference posed by the background fluorescence originating from the nitrocellulose (NC) membrane would significantly impact the sensitivity and accuracy of microsphere-based detection in LFIA. In this work, an attempt was made to extend the π-conjugated system and asymmetric structure of rhodamine fluorophore, resulting in the synthesis of dye molecules (RB2) incorporating double bonds, which can reach an absolute photoluminescence quantum yield (PLQY) of 30.01% in EtOH. Subsequently, carboxyl group functionalized fluorescent microspheres were prepared in a two-step copolymerization via soap-free emulsion polymerization. The obtained microspheres were characterized by scanning electron microscopy, transmission electron microscopy, DLS, Fourier transform infrared spectroscopy, ultraviolet spectrophotometry, and fluorescence spectrophotometry. The results showed that RB2 was successfully copolymerized into the microspheres, and the resulting microspheres had good dispersion and stability with high red fluorescence intensity (λabs ∼ 610 nm, λem ∼ 660 nm). Utilizing these microspheres, the resulting lateral flow immunoassay was successfully found to detect SARS-CoV-2 N protein with a detection limit of 2.5 pg/mL and the linear concentration spanning from 2.5 pg/mL to 10 ng/mL. The results confirm the effectiveness of the synthetic fluorescent microspheres as the label for LFIA.


Assuntos
Corantes Fluorescentes , Polímeros , Microesferas , Imunoensaio , Corantes Fluorescentes/química , Cromatografia de Afinidade/métodos
15.
Carbohydr Polym ; 334: 122039, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553236

RESUMO

Biological processes, such as bone defects healing are precisely controlled in both time and space. This spatiotemporal characteristic inspires novel therapeutic strategies. The sustained-release systems including hydrogels are commonly utilized in the treatment of bone defect; however, traditional hydrogels often release drugs at a consistent rate, lacking temporal precision. In this study, a hybrid hydrogel has been developed by using sodium alginate, sucrose acetate isobutyrate, and electrospray microspheres as the base materials, and designed with ultrasound response, and on-demand release properties. Sucrose acetate isobutyrate was added to the hybrid hydrogel to prevent burst release. The network structure of the hybrid hydrogel is formed by the interconnection of Ca2+ with the carboxyl groups of sodium alginate. Notably, when the hybrid hydrogel is exposed to ultrasound, the ionic bond can be broken to promote drug release; when ultrasound is turned off, the release returned to a low-release state. This hybrid hydrogel reveals not only injectability, degradability, and good mechanical properties but also shows multiple responses to ultrasound. And it has good biocompatibility and promotes osteogenesis efficiency in vivo. Thus, this hybrid hydrogel provides a promising therapeutic strategy for the treatment of bone defects.


Assuntos
Alginatos , Sistemas de Liberação de Medicamentos , Microesferas , Alginatos/química , Regeneração Óssea , Osteogênese , Hidrogéis/química
16.
J Chromatogr A ; 1720: 464785, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38458141

RESUMO

Amphiphilic materials can be used for sample preparation of chromatography or mass spectrometry. Amphiphilic materials with magnetic properties in combination with magnetic suction devices allow for automated sample preparation. However, conventional synthesis methods are cumbersome and not suitable for the mass production of the material. In this study, a micro-suspension polymerization method was developed to synthesize magnetic amphiphilic resin microspheres (MARMs), providing new ideas for the preparation of amphiphilic microspheres. MARMs with particle sizes ranging from 3 to 6 µm were successfully prepared, with BET surface area up to 653.2 m2/g. A magnetic solid-phase extraction method based on MARM-5 was developed for the extraction of four glucocorticoids including Cortisone, Hydrocortisone, Cortodoxone, and Corticosterone. This method had a very short adsorption time of 0.5 min and a total extraction time of only 13 min. The limit of detection for the four glucocorticoids ranged from 0.22 to 0.82 ng/L. There was a good linear relationship between sample concentration and peak area in the range of 25∼500 ng/L. Relative recovery of 98 %∼108 % and internal standard normalized matrix effect factors of 95∼114 % were obtained, and the relative standard deviation was between 2.3 % and 6.3 %. The MARMs would be used as excellent solid extraction material for glucocorticoids.


Assuntos
Glucocorticoides , 60705 , Microesferas , Polimerização , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão
17.
J Nanobiotechnology ; 22(1): 134, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549081

RESUMO

BACKGROUND: Corneal neovascularization (CoNV) threatens vision by disrupting corneal avascularity, however, current treatments, including pharmacotherapy and surgery, are hindered by limitations in efficacy and adverse effects. Minocycline, known for its anti-inflammatory properties, could suppress CoNV but faces challenges in effective delivery due to the cornea's unique structure. Therefore, in this study a novel drug delivery system using minocycline-loaded nano-hydroxyapatite/poly (lactic-co-glycolic acid) (nHAP/PLGA) nanoparticles was developed to improve treatment outcomes for CoNV. RESULTS: Ultra-small nHAP was synthesized using high gravity technology, then encapsulated in PLGA by a double emulsion method to form nHAP/PLGA microspheres, attenuating the acidic by-products of PLGA degradation. The MINO@PLGA nanocomplex, featuring sustained release and permeation properties, demonstrated an efficient delivery system for minocycline that significantly inhibited the CoNV area in an alkali-burn model without exhibiting apparent cytotoxicity. On day 14, the in vivo microscope examination and ex vivo CD31 staining corroborated the inhibition of neovascularization, with the significantly smaller CoNV area (29.40% ± 6.55%) in the MINO@PLGA Tid group (three times daily) than that of the control group (86.81% ± 15.71%), the MINO group (72.42% ± 30.15%), and the PLGA group (86.87% ± 14.94%) (p < 0.05). Fluorescein sodium staining show MINO@PLGA treatments, administered once daily (Qd) and three times daily (Tid) demonstrated rapid corneal epithelial healing while the Alkali injury group and the DEX group showed longer healing times (p < 0.05). Additionally, compared to the control group, treatments with dexamethasone, MINO, and MINO@PLGA were associated with an increased expression of TGF-ß as evidenced by immunofluorescence, while the levels of pro-inflammatory cytokines IL-1ß and TNF-α demonstrated a significant decrease following alkali burn. Safety evaluations, including assessments of renal and hepatic biomarkers, along with H&E staining of major organs, revealed no significant cytotoxicity of the MINO@PLGA nanocomplex in vivo. CONCLUSIONS: The novel MINO@PLGA nanocomplex, comprising minocycline-loaded nHAP/PLGA microspheres, has shown a substantial capacity for preventing CoNV. This study confirms the complex's ability to downregulate inflammatory pathways, significantly reducing CoNV with minimal cytotoxicity and high biosafety in vivo. Given these findings, MINO@PLGA stands as a highly promising candidate for ocular conditions characterized by CoNV.


Assuntos
Neovascularização da Córnea , Minociclina , Humanos , Minociclina/farmacologia , Neovascularização da Córnea/tratamento farmacológico , Neovascularização da Córnea/prevenção & controle , Microesferas , 60489 , Álcalis
18.
Adv Colloid Interface Sci ; 326: 103121, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38457900

RESUMO

Conventional drug delivery systems are associated with various shortcomings, including low bioavailability and limited control over release. Biodegradable polymeric microparticles have emerged as versatile carriers in drug delivery systems addressing all these challenges. This comprehensive review explores the dynamic landscape of microparticles, considering the role of hydrophilic and hydrophobic materials. Within the continuously evolving domain of microparticle preparation methods, this review offers valuable insights into the latest advancements and addresses the factors influencing microencapsulation, which is pivotal for harnessing the full potential of microparticles. Exploration of the latest research in this dynamic field unlocks the possibilities of optimizing microencapsulation techniques to produce microparticles of desired characteristics and properties for different applications, which can help contribute to the ongoing evolution in the field of pharmaceutical science.


Assuntos
Sistemas de Liberação de Medicamentos , Polímeros , Polímeros/química , Microesferas , Preparações Farmacêuticas , Interações Hidrofóbicas e Hidrofílicas
19.
J Med Virol ; 96(3): e29487, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38482901

RESUMO

Human norovirus (HuNoV) is the most predominant viral agents of acute gastroenteritis. Point-of-care testing (POCT) based on lateral flow immunochromatography (LIFC) has become an important tool for rapid diagnosis of HuNoVs. However, low sensitivity and lack of quantitation are the bottlenecks of traditional LIFC. Thus, we established a rapid and accurate technique that combined immunomagnetic enrichment (IM) with LFIC to identify GII HuNoVs in fecal specimens. Before preparing immunofluorescent nanomagnetic microspheres and achieving the effect of HuNoV enrichment in IM and fluorescent signal in LFIC, amino-functionalized magnetic beads (MBs) and carboxylated quantum dots (QDs) were coupled at a mass ratio of 4:10. Anti-HuNoV monoclonal antibody was then conjugated with QDs-MB. The limit of detection was 1.56 × 104 copies/mL, and the quantitative detection range was 1.56 × 104 copies/mL-1 × 106 copies/mL under optimal circumstances. The common HuNoV genotypes GII.2, GII.3, GII.4, and GII.17 can be detected, there was no cross-reaction with various enteric viruses, including rotavirus, astrovirus, enterovirus, and sapovirus. A comparison between IM-LFIC and RT-qPCR for the detection of 87 fecal specimens showed a high level of agreement (kappa = 0.799). This suggested that the method is rapid and sensitive, making it a promising option for point-of-care testing in the future.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Rotavirus , Sapovirus , Humanos , Norovirus/genética , Microesferas , Rotavirus/genética , Sapovirus/genética , Fezes , Infecções por Caliciviridae/diagnóstico
20.
J Sep Sci ; 47(5): e2300746, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38471966

RESUMO

In this work, monodisperse and nano-porous poly(bismaleimide-co-divinylbenzene) microspheres with large specific surface area (427.6 m2 /g) and rich pore structure were prepared by one-pot self-stable precipitation polymerization of 2,2'-bis[4-(4-maleimidophenoxy) phenyl] propane and divinylbenzene. The prepared poly(bismaleimide-co-divinylbenzene) microspheres were employed as dispersive solid-phase extraction (DSPE) adsorbent for the extraction of triazine herbicides. Under optimized conditions, good linearities were obtained between the peak area and the concentration of triazine herbicides in the range of 1-400 µg/L (R2 ≥ 0.9987) with the limits of detection of 0.12-0.31 µg/L. Triazine herbicides were detected using the described approach in vegetable samples (i.e., cucumber, tomato, and maize) with recoveries of 93.6%-117.3% and relative standard deviations of 0.4%-3.5%. In addition, the recoveries of triazine herbicides remained above 80.7% after being used for nine DSPE cycles, showing excellent reusability of poly(bismaleimide-co-divinylbenzene) microspheres. The adsorption of poly(bismaleimide-co-divinylbenzene) microspheres toward triazine herbicides was a monolayer and chemical adsorption. The adsorption mechanism between triazine herbicides and adsorbents might be a combination of hydrogen bonding, electrostatic interaction, and π-π conjugation. The results confirmed the potential use of the poly(bismaleimide-co-divinylbenzene) microspheres-based DSPE coupled to the high-performance liquid chromatography method for the detection of triazine herbicide residues in vegetable samples.


Assuntos
Herbicidas , Verduras , Compostos de Vinila , Verduras/química , Cromatografia Líquida de Alta Pressão/métodos , Microesferas , Porosidade , Triazinas/análise , Extração em Fase Sólida/métodos , Herbicidas/análise , Limite de Detecção
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