Accurate diagnosis of Alzheimer's disease (AD) in its earliest stage can prevent the disease and delay the symptoms. Therefore, more sensitive, non-invasive, and simple screening tools are required ...for the early diagnosis and monitoring of AD. Here, we design a self-assembled nanoparticle-mediated amplified fluorogenic immunoassay (SNAFIA) consisting of magnetic and fluorophore-loaded polymeric nanoparticles. Using a discovery cohort of 21 subjects, proteomic analysis identifies adenylyl cyclase-associated protein 1 (CAP1) as a potential tear biomarker. The SNAFIA demonstrates a low detection limit (236 aM), good reliability (R
= 0.991), and a wide analytical range (0.320-1000 fM) for CAP1 in tear fluid. Crucially, in the verification phase with 39 subjects, SNAFIA discriminates AD patients from healthy controls with 90% sensitivity and 100% specificity in under an hour. Utilizing tear fluid as a liquid biopsy, SNAFIA could potentially aid in long-term care planning, improve clinical trial efficiency, and accelerate therapeutic development for AD.
The eye is an extension of the central nervous system (CNS) and contains aqueous humor (AH), which is a fluid rich in biomolecules secreted from intraocular tissues; thus, this organ allows for ...non-invasive visualization of early changes in CNS disorders. There is a growing interest in developing implantable devices, such as intraocular-lens (IOL), for specific medical uses, including intraocular monitoring. We describe a novel IOL-sensing system for detecting AH biomarkers via biocompatible enzyme-activatable fluorogenic hydrogel sensors. Matrix-metalloproteinase-9, a biomarker of degenerative CNS and eye disorders, was selected as a target. A peptide-probe-incorporated fluorogenic IOL (FIOL) was developed using diacrylamide-group-modified poly(ethyleneglycol) (PEGDAAm) biocompatible hydrogels, adjusting the hydrogel mesh size to allow selective penetration of the target while blocking non-targets, using label-free detection with semi-permanently implantable sensors, and demonstrating the clinical feasibility of FIOL through in vivo testing. This novel FIOL-based sensing system represents a promising approach for liquid biopsy of intraocular fluids.
•The eye allows for early, non-invasive visualization of CNS disorders.•Implantable devices (intraocular-lens) are suitable for intraocular monitoring.•We detected AH biomarkers using enzyme-activatable fluorogenic hydrogel sensors.•FIOL was developed using PEGDAAm biocompatible hydrogels.•We proved the feasibility of FIOL-based sensing system for ocular liquid biopsy.
Synchrotron X-rays can be used to obtain highly detailed images of parts of the lung. However, micro-motion artifacts induced by such as cardiac motion impede quantitative visualization of the ...alveoli in the lungs. This paper proposes a method that applies a neural network for synchrotron X-ray Computed Tomography (CT) data to reconstruct the high-quality 3D structure of alveoli in intact mouse lungs at expiration, without needing ground-truth data. Our approach reconstructs the spatial sequence of CT images by using a deep-image prior with interpolated input latent variables, and in this way significantly enhances the images of alveolar structure compared with the prior art. The approach successfully visualizes 3D alveolar units of intact mouse lungs at expiration and enables us to measure the diameter of the alveoli. We believe that our approach helps to accurately visualize other living organs hampered by micro-motion.
Manganese oxide (MnO) nanocubes were fabricated and their surface were modified by ligand encapsulation or ligand exchange, to render them water-soluble. And then, MnO formed the hollow structure by ...etching using acidic solution (phthalate buffer, pH 4.0). Depending on the ligand of the MnO surface, it increases the interaction between MnO and water molecules. Also, the hollow structure of MnO, as well as the ligand, can greatly enhance the accessibility of water molecules to metal ions by surface area-to-volume ratio. These factors provide high R1 relaxation, leading to strong T1 MRI signal. We have confirmed T1-weighted MR contrast effect using 4-kinds of MnO nanocubes (MnOEn, MnOEnHo, MnOEx and MnOExHo). They showed enough a MR contrast effect and biocompatibility. Especially, among them, MnOExHo exhibited high T1 relaxivity (r1) (6.02 mM
−1
s
−1
), even about 1.5 times higher sensitivity than commercial T1 MR contrast agents. In vitro/in vivo studies have shown that MnOExHo provides highly sensitive T1-weighted MR imaging, thereby improving diagnostic visibility at the disease site.
Multipotent adult stem cells (MASCs) derived from Pluripotent stem cells (PSCs) have found widespread use in various applications, including regenerative therapy and drug screening. For these ...applications, highly pluripotent PSCs need to be selectively separated from those that show low pluripotency for reusage of PSCs, and MASCs need to be collected for further application. Herein, we developed immunomagnetic microfluidic integrated system (IM-MIS) for separation of stem cells depending on potency level. In this system, each stem cell was multiple-separated in microfluidics chip by magnetophoretic mobility of magnetic-activated cells based on the combination of two sizes of magnetic nanoparticles and two different antibodies. Magnetic particles had a difference in the degree of magnetization, and antibodies recognized potency-related surface markers. IM-MIS showed superior cell separation performance than FACS with high throughput (49.5%) in a short time (<15 min) isolate 1 × 107 cells, and higher purity (92.1%) than MACS. IM-MIS had a cell viability of 89.1%, suggesting that IM-MIS had no effect on cell viability during isolation. Furthermore, IM-MIS did not affect the key characteristics of stem cells including its differentiation potency, phenotype, genotype, and karyotype. IM-MIS may offer a new platform for the development of multi-separation systems for diverse stem cell applications.
Immunomagnetic-based microfluidic integrated system (IM-MIS) is developed that combines the technical benefits of FACS and MACS for separation of multiple stem cells, according to their differentiation capacity. It has been confirmed that IM-MIS allows multiple cell separation with high throughput and separation efficiency in a short time without affecting the potency of the stem cells. Display omitted
•Cell potency-mediated multi-sort through immunomagnetic microfluidic system.•Magnetic-activated cells were multiple-separated by magnetophoretic mobility.•Stem cells separated by IM-MIS keeps their potency and characteristics.•IM-MIS has high-throughput and high-sorting efficiency in a short time.•IM-MIS can be applied in the field of stem cell-based regenerative medicine.
As stem cells show great promise in regenerative therapy, stem cell-mediated therapeutic efficacy must be demonstrated through the migration and transplantation of stem cells into target disease ...areas at the pre-clinical level. In this study, we developed manganese-based magnetic nanoparticles with hollow structures (MnOHo) and modified them with the anti-human integrin β1 antibody (MnOHo-Ab) to enable the minimal-invasive monitoring of transplanted human stem cells at the pre-clinical level. Compared to common magnetic resonance imaging (MRI)-based stem cell monitoring systems that use pre-labeled stem cells with magnetic particles before stem cell injection, the MnOHo-Ab is a new technology that does not require stem cell modification to monitor the therapeutic capability of stem cells. Additionally, MnOHo-Ab provides improved T1 MRI owing to the hollow structure of the MnOHo. Particularly, the anti-integrin β1 antibody (Ab) introduced in the MnOHo targets integrin β1 expressed in the entire stem cell lineage, enabling targeted monitoring regardless of the differentiation stage of the stem cells. Furthermore, we verified that intravenously injected MnOHo-Ab specifically targeted human induced pluripotent stem cells (hiPSCs) that were transferred to mice testes and differentiated into various lineages. The new stem cell monitoring method using MnOHo-Ab demonstrates whether the injected human stem cells have migrated and transplanted themselves in the target area during long-term stem cell regenerative therapy.
•New strategy to monitor human stem cell transplantation at the pre-clinical level.•MnOHo-Ab enables minimal-invasive monitoring of in vivo transplanted human cells.•Human integrin β1 antibody of MnOHo-Ab targets transplanted human stem cells.•MnOHo-Ab targets human stem cells regardless of differentiation state.•This system can be applied in various fields of stem cell-based therapy.
The precise control of sensitivity to external stimuli, for example, impact, friction, and thermal energy, has been emphasized for highly energetic materials, including RDX and HMX. Such ...sensitivities could be controlled by adjusting the surface area or (in)organic additives; however, increased stability leads to a decrease in the explosives’ performance. Here, high-energy-density molecules hosted in inverse opal-like porous carbon (IOC) nanocomposites demonstrate the mechanical stabilization and desensitization of RDX and HMX inside the carbon nanostructure using host–guest chemistry techniques. For this strategy, the uniform, vacant voids of the IOC were used to provide internal crystallization for the impact/frictional stabilization of explosives, and also to enhance the thermal reactivity by the high heat conductivity of IOC initiating detonation by thermally induced hotspot. The weight percentage of high explosives hosted by recrystallization at high temperatures and in vacuum reached ∼70%. After high explosives were embedded inside the IOC, the impact, friction and electrostatic stability was greatly increased (2–2.15-fold, 1.86–1.92-fold, and 1.25–2-fold, respectively) compared with free RDX and HMX. Also, addition of PVP as a binder controlled the effectiveness and efficiency of the carbon template, enabling control of the impact and friction sensitivity from 14.72 J to >79.43 J and from 295.81 to 352.80 N, respectively.
The isolation of high-grade (i.e. high-pluripotency) human induced pluripotent stem cells (hiPSCs) is a decisive factor for enhancing the purity of hiPSC populations or differentiation efficiency. A ...non-invasive imaging system that can monitor microRNA (miRNA) expression provides a useful tool to identify and analyze specific cell populations. However, previous studies on the monitoring/isolation of hiPSCs by miRNA expression have limited hiPSCs' differentiation system owing to long-term incubation with miRNA imaging probe-nanocarriers. Therefore, we focused on monitoring high-grade hiPSCs without influencing the pluripotency of hiPSCs. We reduced nanoparticle transfection time, because hiPSCs are prone to spontaneous differentiation under external factors during incubation. The fluorescent nanoswitch ("ON" with target miRNA), which can be applied for either imaging or sorting specific cells by fluorescence signals, contains an miRNA imaging probe (miP) and a PEI-PEG nanoparticle (miP-P). Consequently, this nanoswitch can sense various endogenous target miRNAs within 30 min in vitro, and demonstrates strong potential for not only imaging but also sorting pluripotent hiPSCs without affecting pluripotency. Moreover, miP-P-treated hiPSCs differentiate well into endothelial cells, indicating that miP-P does not alter the pluripotency of hiPSCs. We envisage that this miRNA imaging system could be valuable for identifying and sorting high-grade hiPSCs for improved practical applications.
Various types of nanoprobes have recently been utilized to monitor living organisms by detecting and imaging intracellular biomarkers, such as microRNAs (miRs). We here present a simple one-pot ...method to prepare stellate gold nanoparticles functionalized with miR-detecting molecular beacons (SGNP-MBs); low pH conditions permitted the rapid-high loading of MBs on the surface of SGNPs. Compared to the conventional gold nanoparticle-based MBs, SGNPs carried a 4.5-fold higher load of MBs and exhibited a 6.4-fold higher cellular uptake. We demonstrated that SGNP-MBs were successfully internalized in human gastric cancer cell lines and could be used to accurately detect and image intracellular miRs in an miR-specific manner. Furthermore, the relative levels of intracellular miRs in three different cell lines expressing miR-10b (high, moderate, and low levels) could be monitored using SGNP-MBs. Consequently, these results indicated that SGNP-MBs could have applications as highly potent, efficient nanoprobes to assess intracellular miR levels in living cells.
Considerable attention is given to drug delivery technology that efficiently delivers appropriate levels of drug molecules to diseased sites with significant therapeutic efficacy. Nanotechnology has ...been used to develop various strategies for targeted drug delivery, while controlling the release of drugs because of its many benefits. Here, a delivery system was designed to control drug release by external magnetic fields using porous silica and magnetic nanoparticles. Magnetic nanochains (MNs) of various lengths (MN-1: 1.4 ± 0.8 μm, MN-2: 2.2 ± 1.1 μm, and MN-3: 5.3 ± 2.0 μm) were synthesized by controlling the exposure time of the external magnetic force in magnetic nanoaggregates (MNCs). Mesoporous silica-coated magnetic nanochains (MSMNs) (MSMN-1, MSMN-2, and MSMN-3) were prepared by forming a porous silica layer through sol–gel polymerization. These MSMNs could load the drug doxorubicin (DOX) into the silica layer (DOX-MSMNs) and control the release behavior of the DOX through an external rotating magnetic field. Simulations and experiments were used to verify the motion and drug release behavior of the MSMNs. Furthermore, a bio-receptor (aptamer, Ap) was introduced onto the surface of the DOX-MSMNs (Ap-DOX-MSMNs) that could recognize specific cancer cells. The Ap-DOX-MSMNs demonstrated a strong therapeutic effect on cancer cells that was superior to that of the free DOX. The potent ability of these MSMNs as an external stimulus-responsive drug delivery system was proven.