Loading Platform Research Articles

Automated solid phase DNA extraction on a lab-on-a-disc with two-degrees of freedom instrumentation

BackgroundLab-on-a-disc (LoaD) technology has emerged as a transformative approach for point-of-care diagnostics and high-throughput testing. The promise of integrating multiple laboratory functions onto a single integrated platform has significant implications for healthcare, especially in resource-limited settings. However, one of the primary challenges faced in the design and manufacture of LoaD devices is the integration of effective valving mechanisms. These valves are essential for fluid control and routing, but their intricacy often leads to complexities in design and increased vulnerability to failure. This emphasizes the need for improved designs and manufacturing processes without complex, integrated valving mechanisms. (96) ResultsWe describe a fully automated biological workflow and reagent actuation on a LoaD device without an integrated valving system. The Two Degrees-of-Freedom (2DoF) custom centrifuge alters the centre of rotation, facilitating fluid flow direction changes on the microfluidic platform through a custom programmed interface. A novel 360-degree fluid manipulation approach via secondary planetary gear motion enabled sequential assay reagent actuation without embedded valve triggering, with the addition of infinite incubation times and efficient use of platform realty. The simplified LoaD platform uses clever design, with intermediate flow chambers to avoid cross contamination between reagent steps. Notably, the optimized LoaD platform demonstrated a two-fold DNA yield at higher HEK-293 cell concentrations compared to commercially available spin-column kits. This significantly simplified LoaD platform successfully automated a common, complex workflow without inhibiting DNA purification. (129) SignificanceThis system exhibits the clever coupling of both 2DoF and centrifugal microfluidics to create an autonomous testing package capable of eradicating the need for complex valving systems to automate biological workflows on LoaDs. This automated system has outperformed commercially available DNA extraction kits for higher cell counts. The platform's elimination of valve requirements ensures unlimited sample incubation times and enhances reliability, making it a straightforward option for automated biological workflows, particularly in diagnostics. (73)

Digital process control of multi-step assays on centrifugal platforms using high-low-high rotational-pulse triggered valving.

Due to their capability for comprehensive sample-to-answer automation, the interest in centrifugal microfluidic systems has greatly increased in industry and academia over the last quarter century. The main applications of these "Lab-on-a-Disc" (LoaD) platforms are in decentralised bioanalytical point-of-use / point-of-care testing. Due to the unidirectional and omnipresent nature of the centrifugal force, advanced flow control is key to coordinate multi-step / multi-reagent assay formats on the LoaD. Formerly, flow control was often achieved by capillary burst valves which require gradual increments of the spin speed of the system-innate spindle motor. Recent advanced introduced a flow control scheme called 'rotational pulse actuated valves'. In these valves the sequence of valve actuation is determined by the architecture of the disc while actuation is triggered by freely programmable upward spike (i.e. Low-High-Low (LHL)) in the rotational frequency. This paradigm shift from conventional 'analogue' burst valves to 'digital' pulsing significantly increases the number of sequential while also improving the overall robustness of flow control. In this work, we expand on these LHL valves by introducing High-Low-High (HLH) pulse-actuated (PA) valving which are actuated by 'downward' spike in the disc spin-rate. These HLH valves are particularly useful for high spin-rate operations such as centrifugation of blood. We introduce two different HLH architectures and then combine the most promising with LHL valves to implement the time-dependent liquid handling protocol underlying a common liver function test panel.

Implementing a Precision Pneumatic Plug Tray Seeder with High Seeding Rates for Brassicaceae Seeds via Real-Time Trajectory Tracking Control

In recent years, the aging of the rural population worldwide has become a major concern, necessitating the development of agricultural automation. Pneumatic energy has emerged as a reliable and environmentally friendly option, aiding in the global effort to reduce carbon emissions. The purpose of this study is to reduce the amount of labor required for plug tray seeding by developing an automated seeder that employs a precision pneumatic servo system via the rod-less actuator with real-time trajectory tracking capabilities. The proposed seeder has a simple structure, is easy to maintain, and saves energy. It mainly consists of a rod-less pneumatic cylinder, a needle seeding mechanism, a soil drilling mechanism and a PC-based real-time controller. Mathematical models of the developed precision pneumatic plug tray seeder are analyzed and established, and an adaptive sliding mode controller is proposed. A PC-based real-time control system is developed using MATLAB/SIMULINK via an optical encoder with a sampling frequency of 1 kHz to enable the development of precise pneumatic plug tray seeder. An optical encoder is used to measure the displacement of the rod-less cylinder which represents real-time positions of the plug tray loading platform. Experiments are conducted using Brassicaceae seeds, and the rates of single seeding, multiple seeding, missed seeding and germination are carried out through manual measurement. The results indicate that the seeder exhibits satisfactory performance, with a root mean square error of less than 0.5 mm and a single-seeding rate of more than 97%. Overall, our findings provide new insights for nurseries and could contribute to the reduction in agricultural carbon emissions.

Lightweight Design and Optimization of the Road Wrecker’s Loading Platform

Aiming to realize the lightweight design of the road wrecker’s loading platform, an efficacious method combining material substitution and size optimization is proposed in this paper. The finite element model is established at first. According to the wrecker’s working process, two typical working conditions are determined. Following the proposed stiffness and strength judgment bases, the FEA of the loading platform is carried out under typical working conditions. Finally, on the premise of meeting the basic performance of the materials, the part thickness is reduced by replacing Q235 steel with Q460 high-strength steel. The optimal size is obtained after size optimization based on OptiStruct software. The improved results show that the total mass of the new loading platform decreased by 30.8% compared with the previous structure. The promoted structural performance meets the requirements, which verifies the practicability of the lightweight design method.

The Golden Liposomes: Preparation and Biomedical Applications of Gold-Liposome Nanocomposites

Gold nanoparticles (AuNP) have received a growing attention due to their fascinating physiochemical properties and promising range of biomedical applications including sensing, diagnosis and cancer photothermal ablation. AuNP enjoy brilliant optical properties and ability to convert light into local heat and function as a “nanoheaters” to fight cancer. However, AuNP are poor drug delivery systems as they do not have reservoirs or matrices to achieve an acceptable drug loading efficiency. On the other end, liposome-based nanocarriers do not exhibit such optical properties but are excellent platform for drug loading and they have been proven clinically with a true presence in the market since the FDA approved Doxil® in 1995. Combining the brilliant optical and photothermal properties of AuNP with the excellent drug loading capability of liposome should yield nanocomposites that enjoy the features of both modalities and enable the development of novel and smart drug delivery systems. Therefore, this review discusses the up-to date research on the AuNP-liposome nanocomposites and the current available approaches and protocols for their preparation and characterization. Finally, the biomedical applications of AuNP-liposome nanocomposites and proposed future directions in this field are discussed.

CHANGE OF PULSE FREQUENCY IN HORSES AS AN INDICATOR OF STRESS CAUSED BY LOADING INTO THE TRAILER

Transport and loading into a trailer is a potential source of stress for horses, which can consequently undermine the concept of animal welfare. The study aimed to determine the presence of stress reaction in horses during the loading into the trailer, expressed through a change in pulse frequency as an indicator of stress reaction. The study included 25 horses between the ages of 4 and 20. Heart rate verification was performed using a veterinary stethoscope with a double-sided membrane and controlled by a heart rate monitor. When the horses were resting in the stable (first measurement), a pulse frequency of 29 to 40 bpm was found. The second measurement was performed at the moment of loading when the horses stepped onto the loading platform of the trailer, and pulse frequency values from 42 to 72 bpm were found. The results of the t-test indicate that there is a statistically significant difference in the pulse frequency between the first and second measurements. The results of this study indicate that loading horses into the trailer can cause stress, which is manifested by an increase in pulse frequency. The tendency of horses to easily form habits allows their proper training to reduce the level of stress while loading into trailers, which would contribute to improving the well-being of horses, and at the same time contribute to reducing stress and the risk of injury to horses and staff.

Status and Prospect of Land-based Delivery Platform Technology for Artillery Weapons

Land-based delivery platform technology for artillery weapons is a comprehensive technology to study the adaptability of artillery weapon and land-based delivery platform, and its function is to is to provide transportation and loading platform for artillery and realize tactical mobility and battle mobility of artillery. This paper reviews the important technical progress of China’s artillery weapons in land-based delivery platform technology, contrasts and analyses the research progress at home and abroad, and outlooks the development trend and countermeasures in the field of land-based delivery platform technology for China’s artillery weapons.

The Performance of Isolated Half-Scissor Like Elements Mechanism Under Compression Axial Load

Half-Scissor Like Elements (H-SLEs) deployable mechanism is the prefab scissor based structural mechanism consists of two bars with bolted connection to enable structure change shape. An experimental investigation on the isolated H-SLEs deployable mechanism under compression axial load was presented. A total of twelve specimens were fabricated in two series with six specimens each series were tested on their strength and stability at deployed configuration. The test specimens in series 1 mm thick C75 section were namely S1, S2, S3, S4, S5 and S6 while series 0.75 mm thick C 75 section were namely S7, S8, S9, S10, S11 and S12. The test specimens consist of C 75 and C 100 section which connected with M6, M8 and M10 bolt in grade 8.8. The compression axial load was applied at the center of 3 mm thick loading platform. The experimental results obtained indicated that four types of failure modes observed, i.e. bolt bending failure, section bearing failure, member buckling failure and instability due to horizontal displacement at mid-height of H-SLEs deployable mechanism (Bolted joint area). Among these failure modes, bolt bending failure was dominated the overall structure stability and impacts others failure modes indirectly while section thickness has impacted the buckling and bearing failure. The ultimate load capacity over BS EN 1993 design bearing resistance ratio obtained for M10 bolt was satisfactory. Besides, twisted effect observed during load applied also contributed to the failure modes identified. Thus, the H-SLEs deployable mechanism with stiffener with M10 bolt connection is necessary for future research in the application of spatial deployable structure purposes.

Investigation of Backfill Compaction Effect on Buried Concrete Pipes

The present study deals with the experimental investigation of buried concrete pipes. Concrete pipes are buried in loose and dense conditions of gravelly sand soil and subjected to different surface loadings to study the effects of the backfill compaction on the pipe. The experimental investigation was accomplished using full-scale precast unreinforced concrete pipes with 300 mm internal diameter tested in a laboratory soil box test facility set up for this study. Two loading platforms are used namely, uniform loading platform and patch loading platform. The wheel load was simulated through patch loading platform which have dimensions of 254 mm *508 mm, which is used by AASHTO to model the wheel load of a HS20 truck. The pipe-soil systems were loaded up to pipes collapse. Pipes were instrumented with strain gauges to measure circumferential strains, in addition to dial gauges, for measurements of the pipe vertical deflections and settlement of the loading platforms. The test results indicated that flexure governed the buried pipe behavior. Flexural cracks formed slightly before the ultimate load. A comparison of soil backfill, between a loose and dense compaction, showed that the dense backfill improve largely the pipe installation and the strength ofpipe-soil system

HADES - high heat load testing - facility at CEA-IRFM

A new facility based on an electron beam for the testing of plasma facing components (PFC) has been built at CEA-IRFM (France). The aim of this facility, named HADES (High heAt loaD tESt), is to assess heat removal capabilities of PFCs exposed to high heat flux. The facility can cover thermal fatigue tests, critical heat fluxes and thermal shocks. This facility has been designed in order to provide the maximum performance and flexibility for the qualification of PFCs.This facility has been built collecting a former high heat load platform, named FE200 [1], and located in Le Creusot-France resulting from collaboration between CEA and Framatome in the 90′s. All the systems have been refurbished except the e-beam gun, which has been replaced by a brand new one with 150 kW and 45 kV of maximum power and accelerating voltage, respectively.The HADES e-beam gun will permit to simulate steady state experiments with thermal flux up to a few tens MW/m² and transient events with thermal energy up to 1 GW/m² during a few milliseconds. A programmable sweep system allows several kinds of energy repartition (uniform and peaked), on a ± 25° shooting angle with the normal to the surface.This paper will present in details the technical specifications related to the e-beam gun as well as to the auxiliary systems. Finally, the main results of the commissioning tests and first campaign, achieved at the end of 2020 will be presented.

Double three-phase permanent magnetic motor based on the smallest copper consumption and maximum torque single phase lack of phase compromise and tolerance error control

In multiphase motors, the consumption of stator copper and the output of torque are a pair of constraints affecting motor control performance. According to the constraint relationship between the them, this paper proposes a method to balance the consumption of copper and the output of torque by using the weight coefficient. Through this method, the efficient control of fault-tolerant motors can be realized, and the balance of output torque and efficiency can be realized. Finally, the accuracy of the control strategy is verified by the motor loading platform.

Oral Delivery of Protein Drugs via Lysine Polymer-Based Nanoparticle Platforms.

Oral delivery of proteins has opened a new perspective for the treatment of different diseases. However, advances of oral protein formulation are usually hindered by protein susceptibility and suboptimal absorption in the gastrointestinal tract (GIT). Polymeric nano drug delivery systems are considered revolutionary candidates to solve these issues, which can be preferably tunable against specific delivery challenges. Herein, a tailored family of lysine-based poly(ester amide)s (Lys-aaPEAs) is designed as a general oral protein delivery platform for efficient protein loading and protection from degradation. Insulin, as a model protein, can achieve effective internalization by epithelial cells and efficient transport across the intestinal epithelium layer into the systemic circulation, followed by controlled release in physiological environments. After the oral administration of insulin carried by Lys-aaPEAs with ornamental hyaluronic acid (HA), mice with type 1 diabetes mellitus showed an acceptable hypoglycemic effect with alleviated complications. A successful oral insulin delivery is associated with patient comfort and convenience and simultaneously avoids the risk of hypoglycemia compared with injections, which is of great feasibility for daily diabetes therapy. More importantly, this versatile Lys-aaPEAs polymeric library can be recognized as a universal vehicle for oral biomacromolecule delivery, providing more possibilities for treating various diseases.

Abstract 686: Immunostimulatory gene therapy with oncolytic viruses potentiates the effect of paclitaxel and cisplatin in ovarian cancer

Abstract Ovarian cancer is commonly treated with debulking surgery, followed by a combination of a taxane and a platinum-based chemotherapy. However, >70% of patients relapse within 3 years with tumors resistant to platinum-based agents. 5-year survival is ranging from 30-40%. Thus, delaying recurrence of disease is a high unmet need in ovarian cancer. Combining the chemotherapy regime with immunostimulatory gene therapy utilizing oncolytic viruses as gene vehicles is an attractive treatment option targeting alternative pathways to induce tumor cell death, control tumor growth and prevent development of metastasis. LOAd703 is an oncolytic adenovirus derived from the LOAd platform of replication-restricted Ad5/35 adenoviruses. LOAd703 encodes for the human immunostimulatory genes trimerized, membrane-bound CD40L (TMZ-CD40L) and 4-1BBL, expressed under a CMV promotor which enables gene expression in both tumor cells and tumor stroma while replication is restricted to tumor cells. Herein, we investigated the effect of combining LOAd703 with paclitaxel and cisplatin in vitro and in vivo. Four human ovarian cancer cell lines (CAOV3, COV362, OVCAR3 and PEA2) were treated with LOAd703 alone, in combination with paclitaxel and/or cisplatin or were left untreated. LOAd703 efficiently killed the ovarian cancer cell lines by oncolysis, as evaluated by an MTS cell viability assay. This effect was further improved when LOAd703 was given in combination with paclitaxel and/or cisplatin. Flow cytometry revealed that the ability of LOAd703 to induce expression of the immunostimulatory transgenes TMZ-CD40L and 4-1BBL, was not negatively affected by the combination with paclitaxel and/or cisplatin. The combination treatment was further tested in an in vivo model where BALB/c nu/nu mice were xenografted with 5 million OVCAR3 cells. The mice were subsequently treated with LOAd703 (1 × 10e9 FFU/mouse), both alone as well as in combination with paclitaxel (6mg/kg) and cisplatin (2.5mg/mg). The treatments were given over the course of 4 weeks where LOAd703 was administered intratumorally twice per week while chemotherapy was given intraperitoneally once per week. The results showed that the combination of LOAd703 and the chemotherapeutics controlled tumor growth significantly better than either LOAd703 alone or the standard treatment with paclitaxel and cisplatin. In conclusion, LOAd703 efficiently killed ovarian cancer cell lines in vitro, and could potentiate the effect of standard-of-care chemotherapy. This effect was confirmed in vivo, in which the combination therapy had a better tumor control than the other treatment groups. A clinical trial is ongoing to confirm the effect of adding LOAd703 to different treatment regimes in ovarian cancer (NCT03225989). Citation Format: Sedigheh Naseri, Jonas Härdin, Emma Eriksson, Tanja Lövgren, Gustav Ullenhag, Angelica Loskog. Immunostimulatory gene therapy with oncolytic viruses potentiates the effect of paclitaxel and cisplatin in ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 686.

The HSPB1-p62/SQSTM1 functional complex regulates the unconventional secretion and transcellular spreading of the HD-associated mutant huntingtin protein.

Conformational diseases, such as Alzheimer, Parkinson and Huntington diseases, are part of a common class of neurological disorders characterized by the aggregation and progressive accumulation of proteins bearing aberrant conformations. Huntington disease (HD) has autosomal dominant inheritance and is caused by mutations leading to an abnormal expansion in the polyglutamine (polyQ) tract of the huntingtin (HTT) protein, leading to the formation of HTT inclusion bodies in neurons of affected patients. Interestingly, recent experimental evidence is challenging the conventional view by which the disease pathogenesis is solely a consequence of the intracellular accumulation of mutant protein aggregates. These studies reveal that transcellular transfer of mutated huntingtin protein is able to seed oligomers involving even the wild-type (WT) forms of the protein. To date, there is still no successful strategy to treat HD. Here, we describe a novel functional role for the HSPB1-p62/SQSTM1 complex, which acts as a cargo loading platform, allowing the unconventional secretion of mutant HTT by extracellular vesicles. HSPB1 interacts preferentially with polyQ-expanded HTT compared with the WT protein and affects its aggregation. Furthermore, HSPB1 levels correlate with the rate of mutant HTT secretion, which is controlled by the activity of the PI3K/AKT/mTOR signalling pathway. Finally, we show that these HTT-containing vesicular structures are biologically active and able to be internalized by recipient cells, therefore providing an additional mechanism to explain the prion-like spreading properties of mutant HTT. These findings might also have implications for the turn-over of other disease-associated, aggregation-prone proteins.

Plant pathogen detection on a lab-on-a-disc using solid-phase extraction and isothermal nucleic acid amplification enabled by digital pulse-actuated dissolvable film valves

By virtue of its ruggedness, portability, rapid processing times, and ease-of-use, academic and commercial interest in centrifugal microfluidic systems has soared over the last decade. A key advantage of the LoaD platform is the ability to automate laboratory unit operations (LUOs) (mixing, metering, washing etc.) to support direct translation of ‘on-bench’ assays to ‘on-chip’. Additionally, the LoaD requires just a low-cost spindle motor rather than specialized and expensive microfluidic pumps. Furthermore, when flow control (valves) is implemented through purely rotational changes in this same spindle motor (rather than using additional support instrumentation), the LoaD offers the potential to be a truly portable, low-cost and accessible platform. Current rotationally controlled valves are typically opened by sequentially increasing the disc spin-rate to a specific opening frequency. However, due lack of manufacturing fidelity these specific opening frequencies are better described as spin frequency ‘bands’. With low-cost motors typically having a maximum spin-rate of 6000 rpm (100 Hz), using this ‘analogue’ approach places a limitation on the number of valves, which can be serially actuated thus limiting the number of LUOs that can be automated. In this work, a novel flow control scheme is presented where the sequence of valve actuation is determined by architecture of the disc while its timing is governed by freely programmable ‘digital’ pulses in its spin profile. This paradigm shift to ‘digital’ flow control enables automation of multi-step assays with high reliability, with full temporal control, and with the number of LUOs theoretically only limited by available space on the disc. We first describe the operational principle of these valves followed by a demonstration of the capability of these valves to automate complex assays by screening tomato leaf samples against plant pathogens. Reagents and lysed sample are loaded on-disc and then, in a fully autonomous fashion using only spindle-motor control, the complete assay is automated. Amplification and fluorescent acquisition take place on a custom spin-stand enabling the generation of real-time LAMP amplification curves using custom software. To prevent environmental contamination, the entire discs are sealed from atmosphere following loading with internal venting channels permitting easy movement of liquids about the disc. The disc was successfully used to detect the presence of thermally inactivated Clavibacter michiganensis. Michiganensis (CMM) bacterial pathogen on tomato leaf samples.

An Effective Peptide-Based Platform for Efficient Exosomal Loading and Cellular Delivery of a microRNA.

Exosomes, membrane-bound nanosized vesicles of biologic origin, are known to contain various molecules, e.g., proteins, lipids, and nucleic acids, which contribute to the exosomes' ability to mediate cell-to-cell communication. Recent impediments of artificial nanoparticles in drug delivery, including low cellular uptake, activation of the immune system, and tissue obstacles, have led scientists to engineer exosomes as drug delivery vehicles. Though exosomes possess inherent properties of stability, biocompatibility, low immunogenicity, and capability to cross biological barriers, there is a need to develop technologies that allow the efficient loading of therapeutic materials into exosomes. Here, we introduced a simple peptide-equipped technology that can enhance the cargo-loading potential of exosomes in a mild loading environment. Specifically, a known cell-penetrating peptide, YARA, derived from human immunodeficiency virus-1 trans-activator of transcription, was covalently conjugated with miR-21-5p, a mammalian microRNA. The conjugate YARA-miR-21-5p was then incubated with exosomes, isolated from either mesenchymal stem cells or cancer cells, for loading. Exosomal loading of YARA-miR-21-5p was time-dependent and demonstrated an impressive 18.6-fold increase in efficiency over exosomal loading of miR-21-5p through incubation. After effective cellular uptake, the loaded exosomes rapidly delivered YARA-miR-21-5p into mammalian cells. Relative to unloaded exosomes and free YARA-miR-21-5p, the loaded exosomes significantly enhanced the proliferation, migration, and invasion of human and mouse fibroblasts, which are vital steps in wound healing. This study lays the groundwork for using cell-penetrating peptides as an innovative approach to efficiently load therapeutic cargos, e.g., microRNAs, into exosomes, which can then be employed to deliver the cargos into cells to yield biological effects.

An electrochemiluminescence immunosensor based on multipath signal catalytic amplification integrated in a Cu2+-PEI-Pt/AuNC nanocomposite.

Here, the nanocomposite Cu2+-PEI-Pt/AuNCs with multipath signal catalytic amplification for a peroxydisulfate-dissolved oxygen electrochemiluminescence (ECL) system was prepared to fabricate a sensitive ECL immunosensor. Using polyethyleneimine (PEI), a linear polymer, as the reductant and template, Pt/Au nanochains (Pt/AuNCs) were prepared. Abundant PEI would adsorb on the surface of Pt/AuNCs via Pt-N or Au-N bonds, and further coordinate with Cu2+ to give the final nanocomposite Cu2+-PEI-Pt/AuNCs which possessed multipath signal catalytic amplification for the ECL of the peroxydisulfate-dissolved oxygen system in the presence of H2O2. First, PEI, as an effective co-reactant, could directly enhance the ECL intensity. Second, Pt/AuNCs could not only act as a mimicking enzyme to promote the decomposition of H2O2 to produce more oxygen in situ, but also act as an effective co-reaction accelerator to facilitate the generation of more co-reactive intermediate groups from peroxydisulfate, resulting in an obviously enhanced ECL signal. Then, Cu2+ could also accelerate the decomposition of H2O2 to produce more oxygen in situ, leading to a further improvement of the ECL response. Using Cu2+-PEI-Pt/AuNCs as a loading platform, a sandwiched ECL immunosensor was fabricated. As a result, the obtained ECL immunosensor possessed an ultra-sensitive detection performance for α-1-fetoprotein, providing effective information on the diagnosis and treatment of related diseases.

GNSS Reconstrainted Visual–Inertial Odometry System Using Factor Graphs

Monocular vision sensors are often affected by the rapid direction change in load platform and violent illumination change when the mobile device moves autonomously with high maneuverability. The images collected by the visual sensor will also have a lot of dynamic blur, which together with the weak texture environment reduces the continuity and accuracy of the visual autonomous navigation system. To enhance the stability of the system, in the letter, we propose a vision-led multisource data fusion navigation algorithm. The system combines the visual information for trajectory estimation, adds the inertial measurement unit (IMU) measurement information to the sliding window for optimization, and finally uses the global navigation satellite system (GNSS) data as a reconstraint condition through factor graph optimization to further optimize the trajectory accuracy. Experiments on the public datasets containing a variety of different scene categories show that the trajectory tracking results generated by our algorithm are more complete and stable and can better meet the system’s autonomous navigation requirements.

Dissolvable Film-Controlled Buoyancy Pumping and Aliquoting on a Lab-On-A-Disc

Lab-on-a-Disc (LoaD) has great potential for applications in decentralised bioanalytical testing where speed and robustness are critical. Here, a disc-shaped microfluidic chip is rotated to pump liquid radially outwards; thus, all microfluidic structures must be fitted into the available radial length. To overcome this limitation, several centripetal pumping technologies have been developed. In this work, we combine buoyancy pumping, enabled by displacing aqueous samples and reagents centripetally inwards by a dense liquid (fluorocarbon FC-40), with dissolvable film (DF) to automate a multi-step assay. The DF dissolves in the presence of water but is not in contact with the FC-40. Therefore, the FC-40 can be stored behind the DF membranes and is autonomously released by contact with the arriving aqueous sample. Using this technology, tasks such as blood centrifugation can be located on the disc periphery where ‘disc real estate’ is less valuable and centrifugal forces are higher. To demonstrate this, we use the combination of the buoyancy-driven centripetal pumping with DF barriers to implement a fully automated multi-parameter diagnostic assay on the LoaD platform. The implemented steps include plasma extraction from a structure, automatically triggered metering/aliquoting, and the management of five onboard stored liquid reagents. Critically, we also demonstrate highly accurate aliquoting of reagents using centripetal pumping. We also provide a mathematical model to describe the pumping mechanism and apply lumped-element modelling and Monte Carlo simulation to estimate errors in the aliquoting volumes caused by manufacturing deviations.

2-Mercaptoimidazole selectively etching and thiol-functionalized ZIF-8 metal–organic framework to serve as a multifaceted platform for radical scavenging and Au loading

Zeolite imidazole frameworks (ZIF-8) are a group of metal–organic frameworks (MOFs) that harbor application potential due to their unique high porosity and other physicochemical properties. However, the small cavities, unstable dispersion, and the lack of surface functional groups hinder the practical application of ZIF-8. In this study, we aimed to develop a ZIF-8-based multifaceted platform with hollow structure and abundant functional groups via a simple one-pot method. We synthesized the ZIF-8 with thiol functionalization (ZSH), while 2-mercaptoimidazole was served as both etching agent and functional counterpart. The hollow morphology and the thiol-groups modification were validated by scanning electron microscopy, transmission electron microscopy with energy-disperse X-ray mapping and X-ray photoelectron spectroscopy. The interparticle structure was estimated by Brunauer–Emmmett–Teller and ultraviolet–visible spectroscopy. The hollow architecture, colloidal stable, and thiol-abundant surface endow ZSHs exploiting the antioxidant and anti-inflammatory ability than pristine ZIF-8 toward a broad scale of morphological change with high functionalization degree. Moreover, ZSHs can specifically encapsulate gold nanoparticles in large quantities for further applications. Finally, ZSHs possess good biocompatibility in human cells and in vivo zebrafish model and could potentially protect human cells against oxidative stress. This concept valuably elucidated the new era for functionalized ZIF-8 to apply as the next generation of multifunctional biomaterials.