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1.
Biomaterials ; 313: 122810, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39243673

RESUMEN

The development of biosensing electronics for real-time sweat analysis has attracted increasing research interest due to their promising applications for non-invasive health monitoring. However, one of the critical challenges lies in the sebum interference that largely limits the sensing reliability in practical scenarios. Herein, we report a flexible epidermal secretion-purified biosensing patch with a hydrogel filtering membrane that can effectively eliminate the impact of sebum and sebum-soluble substances. The as-prepared sebum filtering membranes feature a dual-layer sebum-resistant structure based on the poly(hydroxyethyl methacrylate) hydrogel functionalized with nano-brush structured poly(sulfobetaine) to eliminate interferences and provide self-cleaning capability. Furthermore, the unidirectional flow microfluidic channels design based on the Tesla valve was incorporated into the biosensing patch to prevent external sebum contamination and allow effective sweat refreshing for reliable sensing. By seamlessly combining these components, the epidermal secretion-purified biosensing patch enables continuous monitoring of sweat uric acid, pH, and sodium ions with significantly improved accuracy of up to 12 %. The proposed strategy for enhanced sweat sensing reliability without sebum interference shows desirable compatibility for different types of biosensors and would inspire the advances of flexible and wearable devices for non-invasive healthcare.


Asunto(s)
Técnicas Biosensibles , Hidrogeles , Sebo , Sudor , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Humanos , Sebo/metabolismo , Hidrogeles/química , Sudor/química , Epidermis/metabolismo , Dispositivos Electrónicos Vestibles , Microfluídica/métodos , Ácido Úrico/análisis , Membranas Artificiales , Concentración de Iones de Hidrógeno
2.
Nat Commun ; 15(1): 7686, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227569

RESUMEN

The internal microenvironment of a living cell is heterogeneous and comprises a multitude of organelles with distinct biochemistry. Amongst them are biomolecular condensates, which are membrane-less, phase-separated compartments enriched in system-specific proteins and nucleic acids. The heterogeneity of the cell engenders the presence of multiple spatiotemporal gradients in chemistry, charge, concentration, temperature, and pressure. Such thermodynamic gradients can lead to non-equilibrium driving forces for the formation and transport of biomolecular condensates. Here, we report how ion gradients impact the transport processes of biomolecular condensates on the mesoscale and biomolecules on the microscale. Utilizing a microfluidic platform, we demonstrate that the presence of ion concentration gradients can accelerate the transport of biomolecules, including nucleic acids and proteins, via diffusiophoresis. This hydrodynamic transport process allows localized enrichment of biomolecules, thereby promoting the location-specific formation of biomolecular condensates via phase separation. The ion gradients further impart directional motility of condensates, allowing them to exhibit enhanced diffusion along the gradient. Coupled with a reentrant phase behavior, the gradient-induced enhanced motility leads to a dynamical redistribution of condensates that ultimately extends their lifetime. Together, our results demonstrate diffusiophoresis as a non-equilibrium thermodynamic force that governs the formation and transport of biomolecular condensates.


Asunto(s)
Condensados Biomoleculares , Condensados Biomoleculares/metabolismo , Condensados Biomoleculares/química , Difusión , Hidrodinámica , Ácidos Nucleicos/metabolismo , Ácidos Nucleicos/química , Termodinámica , Proteínas/metabolismo , Proteínas/química , Transporte Biológico , Microfluídica/métodos , Separación de Fases
3.
Nat Commun ; 15(1): 8099, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284842

RESUMEN

Clustered regularly interspaced short palindromic repeats (CRISPR)-based editing tools have transformed the landscape of genome editing. However, the absence of a robust and safe CRISPR delivery method continues to limit its potential for therapeutic applications. Despite the emergence of various methodologies aimed at addressing this challenge, issues regarding efficiency and editing operations persist. We introduce a microfluidic gene delivery system, called droplet cell pincher (DCP), designed for highly efficient and safe genome editing. This approach combines droplet microfluidics with cell mechanoporation, enabling encapsulation and controlled passage of cells and CRISPR systems through a microscale constriction. Discontinuities created in cell and nuclear membranes upon passage facilitate the rapid CRISPR-system internalization into the nucleus. We demonstrate the successful delivery of various macromolecules, including mRNAs (~98%) and plasmid DNAs (~91%), using this platform, underscoring the versatility of the DCP and leveraging it to achieve successful genome engineering through CRISPR-Cas9 delivery. Our platform outperforms electroporation, the current state-of-the-art method, in three key areas: single knockouts (~6.5-fold), double knockouts (~3.8-fold), and knock-ins (~3.8-fold). These results highlight the potential of our platform as a next-generation tool for CRISPR engineering, with implications for clinical and biological cell-based research.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Edición Génica/métodos , Humanos , Microfluídica/métodos , Técnicas de Transferencia de Gen , Electroporación/métodos , Células HEK293 , Plásmidos/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética
4.
Proc Natl Acad Sci U S A ; 121(37): e2405342121, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39240970

RESUMEN

Droplet microfluidics has become a very powerful tool in high-throughput screening, including antibody discovery. Screens are usually carried out by physically sorting droplets hosting cells of the desired phenotype, breaking them, recovering the encapsulated cells, and sequencing the paired antibody light and heavy chain genes at the single-cell level. This series of multiple consecutive manipulation steps of rare screening hits is complex and challenging, resulting in a significant loss of clones with the desired phenotype or large fractions of cells with incomplete antibody information. Here, we present fluorescence-activated droplet sequencing, in which droplets showing the desired phenotype are selectively picoinjected with reagents for RT-PCR. Subsequently, light and heavy chain genes are natively paired, fused into a single-chain fragment variant format, and amplified before off-chip transfer and downstream nanopore sequencing. This workflow is sufficiently sensitive for obtaining different paired full-length antibody sequences from as little as five droplets, fulfilling the desired phenotype. Replacing physical sorting by specific sequencing overcomes a general bottleneck in droplet microfluidic screening and should be compatible with many more applications.


Asunto(s)
Anticuerpos , Humanos , Microfluídica/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
5.
Sci Transl Med ; 16(763): eado5366, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39231240

RESUMEN

Blood lactate concentration is an established circulating biomarker for measuring muscle acidity and can be evaluated for monitoring endurance, training routines, or athletic performance. Sweat is an alternative biofluid that may serve similar purposes and offers the advantage of noninvasive collection and continuous monitoring. The relationship between blood lactate and dynamic sweat biochemistry for wearable engineering applications in physiological fitness remains poorly defined. Here, we developed a microfluidic wearable band with an integrated colorimetric timer and biochemical assays that temporally captures sweat and measures pH and lactate concentration. A colorimetric silver nanoplasmonic assay was used to measure the concentration of lactate, and dye-conjugated SiO2 nanoparticle-agarose composite materials supported dynamic pH analysis. We evaluated these sweat biomarkers in relation to blood lactate in human participant studies during cycling exercise of varying intensity. Iontophoresis-generated sweat pH from regions of actively working muscles decreased with increasing heart rate during exercise and was negatively correlated with blood lactate concentration. In contrast, sweat pH from nonworking muscles did not correlate with blood lactate concentration. Changes in sweat pH and blood lactate were observed in participants who did not regularly exercise but not in individuals who regularly exercised, suggesting a relationship to physical fitness and supporting further development for noninvasive, biochemical fitness evaluations.


Asunto(s)
Ejercicio Físico , Ácido Láctico , Piel , Sudor , Humanos , Sudor/química , Sudor/metabolismo , Ejercicio Físico/fisiología , Concentración de Iones de Hidrógeno , Piel/metabolismo , Ácido Láctico/sangre , Ácido Láctico/metabolismo , Microfluídica/métodos , Masculino , Adulto , Femenino , Biomarcadores/metabolismo , Biomarcadores/sangre , Dispositivos Electrónicos Vestibles
6.
Nat Microbiol ; 9(9): 2308-2322, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39227714

RESUMEN

Swimming bacteria navigate chemical gradients using temporal sensing to detect changes in concentration over time. Here we show that surface-attached bacteria use a fundamentally different mode of sensing during chemotaxis. We combined microfluidic experiments, massively parallel cell tracking and fluorescent reporters to study how Pseudomonas aeruginosa senses chemical gradients during pili-based 'twitching' chemotaxis on surfaces. Unlike swimming cells, we found that temporal changes in concentration did not induce motility changes in twitching cells. We then quantified the chemotactic behaviour of stationary cells by following changes in the sub-cellular localization of fluorescent proteins as cells are exposed to a gradient that alternates direction. These experiments revealed that P. aeruginosa cells can directly sense differences in concentration across the lengths of their bodies, even in the presence of strong temporal fluctuations. Our work thus overturns the widely held notion that bacterial cells are too small to directly sense chemical gradients in space.


Asunto(s)
Quimiotaxis , Pseudomonas aeruginosa , Pseudomonas aeruginosa/fisiología , Fimbrias Bacterianas/metabolismo , Microfluídica/métodos , Proteínas Luminiscentes/metabolismo , Proteínas Luminiscentes/genética
7.
Nat Commun ; 15(1): 7740, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39231922

RESUMEN

The physical characterization of proteins in terms of their sizes, interactions, and assembly states is key to understanding their biological function and dysfunction. However, this has remained a difficult task because proteins are often highly polydisperse and present as multicomponent mixtures. Here, we address this challenge by introducing single-molecule microfluidic diffusional sizing (smMDS). This approach measures the hydrodynamic radius of single proteins and protein assemblies in microchannels using single-molecule fluorescence detection. smMDS allows for ultrasensitive sizing of proteins down to femtomolar concentrations and enables affinity profiling of protein interactions at the single-molecule level. We show that smMDS is effective in resolving the assembly states of protein oligomers and in characterizing the size of protein species within complex mixtures, including fibrillar protein aggregates and nanoscale condensate clusters. Overall, smMDS is a highly sensitive method for the analysis of proteins in solution, with wide-ranging applications in drug discovery, diagnostics, and nanobiotechnology.


Asunto(s)
Proteínas , Imagen Individual de Molécula , Imagen Individual de Molécula/métodos , Proteínas/química , Proteínas/análisis , Soluciones , Difusión , Microfluídica/métodos , Hidrodinámica , Técnicas Analíticas Microfluídicas/métodos
8.
Biosens Bioelectron ; 266: 116725, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39232434

RESUMEN

Surface-enhanced Raman spectroscopy (SERS) is a powerful method in analytical chemistry, but its application in real-life medical settings has been limited due to technical challenges. In this work, we introduce an innovative approach that is meant to advance the automation of microfluidics SERS to improve reproducibility and label-free quantification of two widely used therapeutic drugs, methotrexate (MTX) and lamotrigine (LTG), in human serum. Our methodology involves a miniaturized solid-phase extraction (µ-SPE) method coupled to a centrifugal microfluidics disc with incorporated SERS substrates (CD-SERS). The CD-SERS platform enables simultaneous controlled sample wetting and accurate SERS mapping. Together with the assay we implemented a machine learning method based on Partial Least Squares Regression (PLSR) for robust data analysis and drug quantification. The results indicate that combining µ-SPE with CD-SERS (µ-SPE to CD-SERS) led to a substantial improvement in the signal-to-noise ratio compared to combining CD-SERS with ultrafiltration or protein precipitation. The PLSR model enabled us to obtain the limit of detection and quantification for MTX as 2.90 and 8.92 µM, respectively, and for LTG as 10.76 and 32.29 µM. We also validated our µ-SPE to CD-SERS method for MTX against HPLC and immunoassay (p-value <0.05), using patient samples undergoing MTX therapy. In addition, we achieved a satisfactory recovery rate (80%) for LTG when quantifying it in patient samples. Our results show the potential of this newly developed approach as a strategy for therapeutic drugs in point-of-care clinical settings and highlight the benefits of automating label-free SERS assays.


Asunto(s)
Lamotrigina , Metotrexato , Extracción en Fase Sólida , Espectrometría Raman , Humanos , Extracción en Fase Sólida/métodos , Lamotrigina/sangre , Espectrometría Raman/métodos , Metotrexato/sangre , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Límite de Detección , Microfluídica/métodos , Diseño de Equipo , Centrifugación
9.
Anal Chim Acta ; 1326: 342978, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39260910

RESUMEN

Phage display is a vital tool for the discovery and development of affinity reagents such as antibodies and peptides, which have great potential in imaging, molecular recognition, biosensors, targeted delivery and other clinical applications. However, affinity reagents obtained by phage display are often subjected to a process called biopanning, which is considered time-consuming, labor-intensive and lacks accurate control, limiting the acquisition of high-quality affinity reagents. Over the last two decades, several microfluidic approaches have been designed to simplify the conventional biopanning process and to realize precise control. To better understand the advantages of microfluidics over traditional biopanning and the potential of microfluidics for other molecular screening strategies, we provided an overview of recent applications of microfluidics in phage display. Additionally, the next challenges and outlooks are discussed.


Asunto(s)
Técnicas de Visualización de Superficie Celular , Técnicas de Visualización de Superficie Celular/métodos , Técnicas Analíticas Microfluídicas/instrumentación , Biblioteca de Péptidos , Microfluídica/métodos , Humanos , Péptidos/química , Péptidos/análisis
10.
Nat Commun ; 15(1): 7564, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39217165

RESUMEN

Toehold-mediated strand displacement (TMSD) is extensively utilized in dynamic DNA nanotechnology and for a wide range of DNA or RNA-based reaction circuits. Investigation of TMSD kinetics typically relies on bulk fluorescence measurements providing effective, bulk-averaged reaction rates. Information on individual molecules or even base pairs is scarce. In this work, we explore the dynamics of strand displacement processes at the single-molecule level using single-molecule force spectroscopy with a microfluidics-enhanced optical trap supported by state-of-the-art coarse-grained simulations. By applying force, we can trigger and observe TMSD in real-time with microsecond and nanometer resolution. We find TMSD proceeds very rapidly under load with single step times of 1 µs. Tuning invasion efficiency by introducing mismatches allows studying thousands of forward/backward invasion events on a single molecule and analyze the kinetics of the invasion process. Extrapolation to zero force reveals single step times for DNA invading DNA four times faster than for RNA invading RNA. We also study the kinetics of DNA invading RNA, a process that in the absence of force would rarely occur. Our results reveal the importance of sequence effects for the TMSD process and have relevance for a wide range of applications in nucleic acid nanotechnology and synthetic biology.


Asunto(s)
ADN , Nanotecnología , ARN , ADN/química , Cinética , ARN/química , Nanotecnología/métodos , Imagen Individual de Molécula/métodos , Pinzas Ópticas , Análisis Espectral/métodos , Microfluídica/métodos , Microscopía de Fuerza Atómica/métodos
11.
Proc Natl Acad Sci U S A ; 121(34): e2410164121, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39145927

RESUMEN

In the age of information explosion, the exponential growth of digital data far exceeds the capacity of current mainstream storage media. DNA is emerging as a promising alternative due to its higher storage density, longer retention time, and lower power consumption. To date, commercially mature DNA synthesis and sequencing technologies allow for writing and reading of information on DNA with customization and convenience at the research level. However, under the disconnected and nonspecialized mode, DNA data storage encounters practical challenges, including susceptibility to errors, long storage latency, resource-intensive requirements, and elevated information security risks. Herein, we introduce a platform named DNA-DISK that seamlessly streamlined DNA synthesis, storage, and sequencing on digital microfluidics coupled with a tabletop device for automated end-to-end information storage. The single-nucleotide enzymatic DNA synthesis with biocapping strategy is utilized, offering an ecofriendly and cost-effective approach for data writing. A DNA encapsulation using thermo-responsive agarose is developed for on-chip solidification, not only eliminating data clutter but also preventing DNA degradation. Pyrosequencing is employed for in situ and accurate data reading. As a proof of concept, DNA-DISK successfully stored and retrieved a musical sheet file (228 bits) with lower write-to-read latency (4.4 min of latency per bit) as well as superior automation compared to other platforms, demonstrating its potential to evolve into a DNA Hard Disk Drive in the future.


Asunto(s)
ADN , Microfluídica , ADN/biosíntesis , Microfluídica/métodos , Microfluídica/instrumentación , Análisis de Secuencia de ADN/métodos , Almacenamiento y Recuperación de la Información/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
12.
Mol Biol Rep ; 51(1): 896, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115550

RESUMEN

CRISPR-based (Clustered regularly interspaced short palindromic repeats-based) technologies have revolutionized molecular biology and diagnostics, offering unprecedented precision and versatility. However, challenges remain, such as high costs, demanding technical expertise, and limited quantification capabilities. To overcome these limitations, innovative microfluidic platforms are emerging as powerful tools for enhancing CRISPR diagnostics. This review explores the exciting intersection of CRISPR and microfluidics, highlighting their potential to revolutionize healthcare diagnostics. By integrating CRISPR's specificity with microfluidics' miniaturization and automation, researchers are developing more sensitive and portable diagnostic tools for a range of diseases. These microfluidic devices streamline sample processing, improve diagnostic performance, and enable point-of-care applications, allowing for rapid and accurate detection of pathogens, genetic disorders, and other health conditions. The review discusses various CRISPR/Cas systems, including Cas9, Cas12, and Cas13, and their integration with microfluidic platforms. It also examines the advantages and limitations of these systems, highlighting their potential for detecting DNA and RNA biomarkers. The review also explores the key challenges in developing and implementing CRISPR-driven microfluidic diagnostics, such as ensuring robustness, minimizing cross-contamination, and achieving robust quantification. Finally, it highlights potential future directions for this rapidly evolving field, emphasizing the transformative potential of these technologies for personalized medicine and global health.


Asunto(s)
Sistemas CRISPR-Cas , Microfluídica , Sistemas CRISPR-Cas/genética , Humanos , Microfluídica/métodos , Patología Molecular/métodos , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Técnicas de Diagnóstico Molecular/métodos , Edición Génica/métodos , Dispositivos Laboratorio en un Chip
13.
Sci Rep ; 14(1): 18713, 2024 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134607

RESUMEN

This study focuses on the use of pulsed electric fields (PEF) in microfluidics for controlled cell studies. The commonly used material for soft lithography, polydimethylsiloxane (PDMS), does not fully ensure the necessary chemical and mechanical resistance in these systems. Integration of specific analytical measurement setups into microphysiological systems (MPS) are also challenging. We present an off-stoichiometry thiol-ene (OSTE)-based microchip, containing integrated electrodes for PEF and transepithelial electrical resistance (TEER) measurement and the equipment to monitor pH and oxygen concentration in situ. The effectiveness of the MPS was empirically demonstrated through PEF treatment of the C6 cells. The effects of PEF treatment on cell viability and permeability to the fluorescent dye DapI were tested in two modes: stop flow and continuous flow. The maximum permeability was achieved at 1.8 kV/cm with 16 pulses in stop flow mode and 64 pulses per cell in continuous flow mode, without compromising cell viability. Two integrated sensors detected changes in oxygen concentration before and after the PEF treatment, and the pH shifted towards alkalinity following PEF treatment. Therefore, our proof-of-concept technology serves as an MPS for PEF treatment of mammalian cells, enabling in situ physiological monitoring.


Asunto(s)
Supervivencia Celular , Concentración de Iones de Hidrógeno , Animales , Impedancia Eléctrica , Oxígeno/metabolismo , Electricidad , Microfluídica/métodos , Microfluídica/instrumentación , Ratas , Dispositivos Laboratorio en un Chip , Línea Celular Tumoral , Dimetilpolisiloxanos/química , Sistemas Microfisiológicos
14.
Nat Biomed Eng ; 8(8): 941-962, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39187664

RESUMEN

Microphysiological systems (MPSs) are cellular models that replicate aspects of organ and tissue functions in vitro. In contrast with conventional cell cultures, MPSs often provide physiological mechanical cues to cells, include fluid flow and can be interlinked (hence, they are often referred to as microfluidic tissue chips or organs-on-chips). Here, by means of examples of MPSs of the vascular system, intestine, brain and heart, we advocate for the development of standards that allow for comparisons of quantitative physiological features in MPSs and humans. Such standards should ensure that the in vivo relevance and predictive value of MPSs can be properly assessed as fit-for-purpose in specific applications, such as the assessment of drug toxicity, the identification of therapeutics or the understanding of human physiology or disease. Specifically, we distinguish designed features, which can be controlled via the design of the MPS, from emergent features, which describe cellular function, and propose methods for improving MPSs with readouts and sensors for the quantitative monitoring of complex physiology towards enabling wider end-user adoption and regulatory acceptance.


Asunto(s)
Dispositivos Laboratorio en un Chip , Humanos , Animales , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/métodos , Modelos Biológicos , Encéfalo/fisiología , Diseño de Equipo , Sistemas Microfisiológicos
15.
Biofabrication ; 16(4)2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39121873

RESUMEN

Current biofabrication strategies are limited in their ability to replicate native shape-to-function relationships, that are dependent on adequate biomimicry of macroscale shape as well as size and microscale spatial heterogeneity, within cell-laden hydrogels. In this study, a novel diffusion-based microfluidics platform is presented that meets these needs in a two-step process. In the first step, a hydrogel-precursor solution is dispersed into a continuous oil phase within the microfluidics tubing. By adjusting the dispersed and oil phase flow rates, the physical architecture of hydrogel-precursor phases can be adjusted to generate spherical and plug-like structures, as well as continuous meter-long hydrogel-precursor phases (up to 1.75 m). The second step involves the controlled introduction a small molecule-containing aqueous phase through a T-shaped tube connector to enable controlled small molecule diffusion across the interface of the aqueous phase and hydrogel-precursor. Application of this system is demonstrated by diffusing co-initiator sodium persulfate (SPS) into hydrogel-precursor solutions, where the controlled SPS diffusion into the hydrogel-precursor and subsequent photo-polymerization allows for the formation of unique radial stiffness patterns across the shape- and size-controlled hydrogels, as well as allowing the formation of hollow hydrogels with controllable internal architectures. Mesenchymal stromal cells are successfully encapsulated within hollow hydrogels and hydrogels containing radial stiffness gradient and found to respond to the heterogeneity in stiffness through the yes-associated protein mechano-regulator. Finally, breast cancer cells are found to phenotypically switch in response to stiffness gradients, causing a shift in their ability to aggregate, which may have implications for metastasis. The diffusion-based microfluidics thus finds application mimicking native shape-to-function relationship in the context of tissue engineering and provides a platform to further study the roles of micro- and macroscale architectural features that exist within native tissues.


Asunto(s)
Hidrogeles , Microfluídica , Ingeniería de Tejidos , Hidrogeles/química , Humanos , Microfluídica/métodos , Microfluídica/instrumentación , Células Madre Mesenquimatosas/citología
16.
Int J Pharm ; 664: 124641, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39191334

RESUMEN

Microfluidic mixing is recognized as a convenient method to produce liposomes for its scalability and reproducibility. Numerous studies have described the effect of process parameters such as flow rate ratios and total flow rate on size and size distribution of vesicles. In this work, we focused our attention on the effect of flow rate ratios on the encapsulation efficiency of liposomes, as we hypothesized that different amount of residual organic solvent could affect the retention of lipophilic drug molecules within the bilayer. In a further step, we investigated how the liposomes integrity and loading were impacted by different methods of solvent removal: direct dialysis and dilution & dialysis. Liposomes were prepared by rapidly mixing an ethanolic solution of lipids and a model drug with buffer in a herringbone micromixer, employing four different flow rate ratios (FRR, 4:1, 7:3, 3:2, 1:1). Quercetin, resveratrol and ascorbyl palmitate were used as model antioxidant drugs with different lipophilicity. Data showed that liposomes produced using lower flow rate ratios (i.e., with more residual ethanol) had lower encapsulation efficiencies as well as a more prominent loss of lipids from the bilayer following purification with direct dialysis. If the amount of residual ethanol was reduced to 5% (dilution & dialysis method), the lipids and drug leakage was prevented. Such effect was correlated with the drug aggregation propensity in different ethanol/water mixtures measured by molecular dynamics simulations. Overall, these results highlight the need to tailor the purification method basing on the molecular properties of the loaded drug to ensure high encapsulation and limit the waste of material.


Asunto(s)
Composición de Medicamentos , Lípidos , Liposomas , Microfluídica , Microfluídica/métodos , Lípidos/química , Composición de Medicamentos/métodos , Solventes/química , Antioxidantes/química , Antioxidantes/administración & dosificación , Resveratrol/química , Resveratrol/administración & dosificación , Tamaño de la Partícula , Quercetina/química , Etanol/química
17.
Theranostics ; 14(11): 4352-4374, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113805

RESUMEN

The female reproductive system is essential to women's health, human reproduction and societal well-being. However, the clinical translation of traditional research models is restricted due to the uncertain effects and low efficiency. Emerging evidence shows that microfluidic chips provide valuable platforms for studying the female reproductive system, while no paper has ever comprehensively discussed the topic. Here, a total of 161 studies out of 14,669 records are identified in PubMed, Scopus, Web of Science, ScienceDirect and IEEE Xplore databases. Among these, 61 studies focus on oocytes, which further involves culture, cell surgeries (oocyte separation, rotation, enucleation, and denudation), evaluation and cryopreservation. Forty studies investigate embryo manipulation via microfluidic chips, covering in vitro fertilization, cryopreservation and functional evaluation. Forty-six studies reconstitute both the physiological and pathological statuses of in vivo organs, mostly involved in placenta and fetal membrane research. Fourteen studies perform drug screening and toxicity testing. In this review, we summarize the current application of microfluidic chips in studying the female reproductive system, the advancements in materials and methods, and discuss the future challenges. The present evidence suggests that microfluidic chips-assisted reproductive system reconstruction is promising and more studies are urgently needed.


Asunto(s)
Dispositivos Laboratorio en un Chip , Femenino , Humanos , Animales , Microfluídica/métodos , Oocitos/fisiología , Criopreservación/métodos , Reproducción/fisiología , Embarazo , Técnicas Reproductivas Asistidas , Genitales Femeninos/fisiología
18.
Int J Biol Macromol ; 278(Pt 2): 134603, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39128747

RESUMEN

Wounds refer to physical injuries in which the integrity of the skin or other body organs is disturbed. Wound care includes proper management and treatment of the injuries to promote healing while avoiding infection. Here, a core-shell scaffold is developed comprising polyethylene glycol/silk fibroin-chitosan nanoparticles loaded with curcumin. Chitosan nanoparticles and PEG/Silk fibrous scaffold were synthesized by a microfluidic system and electrospinning technique, respectively. TEM, DLS, and FTIR techniques were used to examine the nanoparticles; whereas nanofibers were characterized by SEM, TEM, and FTIR. Drug loading and release from nanoparticles and scaffolds were assessed by optical spectroscopy. MTT assay and hemolysis test were performed to examine the toxicity of the scaffolds. The hydrophobicity or hydrophilicity of nanofibers was explored by the contact angle test. Scaffolds were examined on the full-thickness wound created on Wistar rats, followed by histological analyses and coagulation tests. The results of FTIR, TEM, and SEM indicated the proper distribution of nanoparticles and core-shell scaffold. The drug loading was about 3 %. About 80 % of the drug was released in the first 7 days. Scaffolds showed hydrophobic properties (114.63° ± 3.6) with no cytotoxicity. The proposed scaffold was able to close 94 % of the wound era after 14 days in the animal model and positively affected re-epithelization and angiogenesis. Moreover, nanofibers containing chitosan nanoparticles exhibited a proper blood coagulation ability in the tail cut model. Finally, it was found that this scaffold, in addition to a biological dressing, can be considered as a drug delivery, and according to the results obtained, this dressing has hydrophobic properties and has also shown good performance against superficial bleeding coagulation. And it has not shown any cytotoxicity for red blood cells and mesenchymal stem cells.


Asunto(s)
Quitosano , Curcumina , Nanopartículas , Polietilenglicoles , Cicatrización de Heridas , Animales , Quitosano/química , Curcumina/química , Curcumina/farmacología , Curcumina/administración & dosificación , Cicatrización de Heridas/efectos de los fármacos , Nanopartículas/química , Polietilenglicoles/química , Ratas , Ratas Wistar , Andamios del Tejido/química , Fibroínas/química , Masculino , Microfluídica/métodos , Liberación de Fármacos , Interacciones Hidrofóbicas e Hidrofílicas , Portadores de Fármacos/química , Hemólisis/efectos de los fármacos
19.
ACS Appl Mater Interfaces ; 16(35): 46113-46122, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39178237

RESUMEN

The urgent need for real-time and noninvasive monitoring of health-associated biochemical parameters has motivated the development of wearable sweat sensors. Existing electrochemical sensors show promise in real-time analysis of various chemical biomarkers. These sensors often rely on labels and redox probes to generate and amplify the signals for the detection and quantification of analytes with limited sensitivity. In this study, we introduce a molecularly imprinted polymer (MIP)-based biochemical sensor to quantify a molecular biomarker in sweat using electrochemical impedance spectroscopy, which eliminates the need for labels or redox probes. The molecularly imprinted biosensor can achieve sensitive and specific detection of cortisol at concentrations as low as 1 pM, 1000-fold lower than previously reported MIP cortisol sensors. We integrated multimodal electrochemical sensors with an iontophoresis sweat extraction module and paper microfluidics for real-time sweat analysis. Several parameters can be simultaneously quantified, including sweat volume, secretion rate, sodium ion, and cortisol concentration. Paper microfluidic modules not only quantify sweat volume and secretion rate but also facilitate continuous sweat analysis without user intervention. While we focus on cortisol sensing as a proof-of-concept, the molecularly imprinted wearable sensors can be extended to real-time detection of other biochemicals, such as protein biomarkers and therapeutic drugs.


Asunto(s)
Biomarcadores , Técnicas Biosensibles , Hidrocortisona , Papel , Sudor , Dispositivos Electrónicos Vestibles , Sudor/química , Humanos , Biomarcadores/análisis , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Hidrocortisona/análisis , Impresión Molecular , Microfluídica/instrumentación , Microfluídica/métodos , Polímeros Impresos Molecularmente/química , Espectroscopía Dieléctrica/instrumentación
20.
Biomed Phys Eng Express ; 10(5)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39142294

RESUMEN

Purpose. This review aims to highlight current improvements in microfluidic devices designed for digestive cancer simulation. The review emphasizes the use of multicellular 3D tissue engineering models to understand the complicated biology of the tumor microenvironment (TME) and cancer progression. The purpose is to develop oncology research and improve digestive cancer patients' lives.Methods. This review analyzes recent research on microfluidic devices for mimicking digestive cancer. It uses tissue-engineered microfluidic devices, notably organs on a chip (OOC), to simulate human organ function in the lab. Cell cultivation on modern three-dimensional hydrogel platforms allows precise geometry, biological components, and physiological qualities. The review analyzes novel methodologies, key findings, and technical progress to explain this field's advances.Results. This study discusses current advances in microfluidic devices for mimicking digestive cancer. Micro physiological systems with multicellular 3D tissue engineering models are emphasized. These systems capture complex biochemical gradients, niche variables, and dynamic cell-cell interactions in the tumor microenvironment (TME). These models reveal stomach cancer biology and progression by duplicating the TME. Recent discoveries and technology advances have improved our understanding of gut cancer biology, as shown in the review.Conclusion. Microfluidic systems play a crucial role in modeling digestive cancer and furthering oncology research. These platforms could transform drug development and treatment by revealing the complex biology of the tumor microenvironment and cancer progression. The review provides a complete summary of recent advances and suggests future research for field professionals. The review's major goal is to further medical research and improve digestive cancer patients' lives.


Asunto(s)
Dispositivos Laboratorio en un Chip , Ingeniería de Tejidos , Microambiente Tumoral , Humanos , Ingeniería de Tejidos/métodos , Microfluídica/métodos , Neoplasias del Sistema Digestivo , Modelos Biológicos , Hidrogeles/química , Animales
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