Biomedical Microdevices最新文献

Increasing drug-facilitated crimes, mainly sexual assaults have intensified the necessity of accessible and efficient methods for club drugs detection especially in biological matrices and beverages that are served at parties and clubs. The recent development of 3D printing technology has markedly accelerated. One prominent application is the fabrication of wearable electrochemical sensors for the selective and sensitive detection of club drugs such as amphetamine. This class of drug is used as a stimulant in the treatment of conditions including attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. Monitoring amphetamine type drugs level in human body is critical due to the risks associated with its possible misuses and related health concerns. By employing the use of 3D printing, makers can create complex and customized sensors specially intended for drug detection. This compliance facilitates integrating diverse type of sensors, thereby improving detection accuracy also. Conventional diagnostic methods are frequently labor-intensive and time-consuming, positioning 3D printed sensors as an innovative approach for real-time monitoring applications. Integrating 3D printing technology in sensor development holds significant potential to transform personalized healthcare by enabling accurate, rapid, and safe detection of amphetamine. This novel study shows the development of a screen-printed paper based electrochemical device with a 3D printed wristband cassette design named “3DP-PWC”. This 3D printed paper based wristband cassette (3DP-PWC) features modified electrodes with amphetamine binding aptamer and copper nanoparticles (CuNPs). For electrochemical study, cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) were used and further validated the sensor’s performance. Developed sensor demonstrated versatility across various beverage types (alcoholic and non-alcoholic) and biological matrices such as synthetic urine. The developed sensor achieved a low detection limit (LOD) of ~0.02 μg/mL with a linear range between 0.01 to 7 μg/mL. Promising results were obtained at an optimum response time of approximately 25 seconds.

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Current endovascular aneurysm treatments rely on catheter-based delivery systems, which inherently restrict access to tortuous anatomies and small-caliber vessels. To address this limitation, we introduce a tetherless microdevice platform that combines magnetic guidance with near-infrared (NIR) triggered shape-memory polymer (SMP) deployment for wireless aneurysm therapy. In this system, an external actuator magnet steers a microdevice-integrated effector magnet through anatomically realistic silicone vascular phantoms, while melanin-doped PLA structures enable precise NIR-induced shape recovery. Because NIR light penetrates biological tissue, deployment can be activated non-invasively from outside the body. The platform supports two device architectures tailored to different clinical needs: a spiral flow disruptor with a retrievable magnet for partial inflow modulation and a petalloid occluder designed for permanent sealing of narrow-neck aneurysms. Their navigation behavior was modelled using a flow-responsive, magnetically modulated stick–slip (F-MMSS) framework that captures the influence of pulsatile flow and wall interactions. Experimentally, magnetic steering was demonstrated under physiologically relevant flow rates and NIR activation achieved reliable deployment through ex vivo tissue. Particle image velocimetry and computational fluid dynamics confirmed substantial reductions in intra-aneurysmal velocity across multiple geometries. Material characterization further verified that PLA–melanin composites exhibit suitable bio and hemocompatibility for preliminary use. Together, these results establish a proof-of-concept platform for wireless navigation and remote deployment of endovascular microdevices, motivating future in vivo evaluation.

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Schematic illustration of a magnetically guided, NIR-triggered microdevice enabling targeted deployment of shape-memory occluders for aneurysm and tumor vessel therapy.

This review focuses on the recent progress in electrochemical biosensors, which are emerging as innovative, sensitive, and cost-efficient platforms for identifying and monitoring biomarkers associated with neurodegeneration. We examine the basic principles behind the operation of electrochemical biosensors, emphasizing the significance of bioreceptors and transducers, as well as the influence of electrode materials such as metals, carbon-based nanomaterials, and conducting polymers (CPs) on the sensors’ performance. The role of nanotechnology is highlighted for its capacity to improve signal transduction, bioreceptor immobilization, and the detection of multiple targets, all while ensuring miniaturization and portability. Additionally, we outline recent approaches for enhancing signal amplification and optimizing performance across various biosensor generations. The use of these biosensors in detecting protein aggregates, genetic mutations, and exosomal biomarkers is reviewed in the context of early diagnosis and tracking disease progression. Finally, the paper discusses current challenges and suggests future directions to aid the clinical application of electrochemical biosensors in diagnosing neurodegenerative diseases. Major barriers impeding the transition of these technologies to clinical approach are discussed along with the variability in performance with real patient samples, lack of reproducibility, scaling up the synthesis of nanomaterials, and the requirement for changes in standardized validation and regulation.

The expression levels of miRNAs in cells or biological fluids are closely associated with the onset and progression of many diseases, making the detection of miRNAs in serum and plasma increasingly important. However, due to the low levels of miRNAs in biological fluids and the complexity of their surrounding environment, their analysis faces challenges related to accuracy and reproducibility. We developed a duplex-specific nuclease (DSN)-mediated detection method for the direct detection of miRNA-21 in real samples. This method eliminates the need for total RNA extraction from real samples using commercial kits, a key advantage over traditional methods requiring pre-treatment. As verified by performance evaluation, this method exhibits a linear range of 5.00 fmol·L^− 1 to 500 pmol·L^− 1 and a limit of detection (LOD) of 2.66 fmol·L^− 1 for miRNA-21. Direct detection of miRNA-21 in real samples yielded favorable results. These findings confirm that the method holds great application potential for the direct detection of miRNA-21 in real biological samples and exhibits promising prospects in clinical cancer diagnosis and drug screening.

Once implanted, biodegradable devices gradually deteriorate, potentially compromising clinical performance. Consequently, evaluating the alterations in physicochemical characteristics after implantation is crucial. Nonetheless, there is currently no established methodology for precisely assessing these alterations. This study sought to develop accurately simulated cranial defect physiological conditions (SCDPC) and examine the physicochemical modifications in biodegradable cranioplasty plates (BCP) to anticipate their performance changes following implantation in humans. We analyzed the physicochemical property alterations of BCP following 24 weeks of exposure to SCDPC. Following 24 weeks under SCDPC, the BCP showed a notable reduction in mass (− 0.79%) and tensile strength (− 69.30%). A decrease in molecular weight was noted after 12 weeks of implantation in rabbits (− 9.67%) and following 12 weeks of exposure to SCDPC (− 4.73%). The physicochemical alterations identified under simulated in vitro cranial defect conditions closely mirrored those found in the in vivo setting. In summary, assessing BCP under SCDPC offers an innovative and dependable approach for precisely forecasting performance shifts after implantation. This strategy could provide meaningful guidance for the advancement of BCP and various other biodegradable medical devices.

Roughly 5% of the population is affected by hearing loss. In case of a functional middle ear impairment with decreased transmission, different types of active middle ear implants may restore hearing. To drive the round window membrane (RWM) for example, bone anchored actuators or floating mass transducer (FMT) have been used in clinics. Bone anchored devices are usually too big for the round window niche and FMTs display low displacement and force at low frequencies. This paper focuses on the stimulation of the RWM by a stator-based actuator that combines small size and bone anchoring. The design features a rotational-symmetric balanced armature core with flexible membrane parts manufactured micro technologically. Membranes and assembled prototypes were evaluated on the bench in the range of 0.1 kHz – 10 kHz and prototypes tested in human temporal bones. We demonstrate the feasibility of a balanced armature actuator of appropriate size for RW placement. With 1.4 mm outer diameter and 4.9 mm length, the actuator fits the anatomical constraints. Acoustic stimulation of the RWM resulted in a maximum output of approximately 80 eq. dB SPL at 300 Hz increasing to > 100 eq. dB SPL above 5 kHz. The measured output is comparable to clinically used devices. The design lacked sufficient robustness leading to a low yield in manufacturing and failures in experiments, although the output level was insensitive to static force loading up to 30 mN. Future developments require an increased maximum output level and improved robustness.

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Radiotherapy (RT) is widely used for malignant tumors ablation in the clinic. However, redundant doses of X-rays might cause irreversible side effects in the periphery of tumor sites. To address this, the convergence of low-dose RT with a novel therapeutic method is promising. Here, a hydrogel system was created that combines nanozymes with NIR-II photothermal therapy and RT sensitization. Meteor hammer-like nanozyme Au-MnOx and agarose hydrogel were mixed to form multifunctional nanozyme hydrogel (MNH). The system experienced a reduction in MNH hardness when exposed to 1064 nm laser irradiation, allowing the release of Au-MnOx to react with H₂O₂ in the tumor microenvironment, resulting in the production of ·OH, which destroys bioactive substances and increases oxidative stress. This process also improves the effectiveness of hyperthermia in photothermal therapy (PTT). In addition, MNH-baed PTT enhances the RT sensitivity. Additionally, Au, with a high atomic number emits X-rays, leading to the generation of reactive oxygen species (ROS) through preexisting processes, which enhances radiation-induced DNA damage. Notably, the in vivo results indicated that MNH + NIR + RT could achieve a potent tumor inhibition rate with negligible side effects to normal tissues. This work paves a new avenue for novel nanozyme-based radiosensitization.