Portable Test System Research Articles

Endotoxin quality control testing for CAR T-cell manufacturing: validation considerations for Endosafe portable testing system

Background & Aim Background Adoptive cell therapies have emerged as promising treatments for cancer patients. The manufacture of clinical-grade Chimeric Antigen Receptor (CAR) T-cells therapies encompass multiple complex processes under the code of good manufacturing practice (cGMP) to ensure high-quality and safe products. Endotoxins are lipo-polysaccharides from gram-negative bacteria that cause serious adverse events in patients. For this reason, it is important that CAR T-cells are tested for endotoxin content. The limulus amoebocyte lysate (LAL) test is FDA approved and allows sensitive detection of bacterial endotoxins. The Endosafe Portable Testing System (PTS) is a rapid, FDA approved testing system manufactured by Charles River that uses disposable cartridges for accurate real-time endotoxin testing, However, a number of important parameters need to be considered when establishing Endosafe-PTS testing for CAR T-cells products. Aim To determine endotoxin limits, maximum valid dilution of samples and reproducibility of the Endosafe-PTS test. Methods, Results & Conclusion Methods Inhibition and enhancement screening cartridges were used initially to establish maximum valid dilution and investigate potential inhibition of the test. CAR T-cells were manufactured from three individuals and analysed for endotoxins on the Endosafe-PTS using cartridges with a sensitivity of 5-0.05 EU/mL and spike recovery 50-200% according to manufacturer's protocol. Three replicates of each sample were tested. Results The optimal dilution of CAR T-cell product was determined at 1:20 with the spike recovery of 84% to 130%. No inhibition was detected at the 1:20 dilution for all three samples. The upper limit of acceptance criteria for endotoxin was determined on the basis of dose and FDA guidelines to be 5 EU/kg body weight/hour of intended product administration. Conclusion The Endosafe-PTS provides an accurate, reproducible and rapid method for Endotoxin detection which is crucial in quality control release testing and administration of time-sensitive CAR T-cell products. It is important to validate inhibition and enhancement screening for each CAR T-cell product and determine the optimal sample dilution before implementation of the Endosafe-PTS for product release testing.

A Research Study for the Design of a Portable and Configurable Ground Test System for the A400M Aircraft

This paper presents a study of the most suitable ground test equipment for the Airbus A400M aircraft aimed at optimizing a design that combines portability, flexibility, and configurability. The study is based on current trends in the configuration of the different parts that are involved in the process of designing Aircraft Interface Modules (AIMs). Researches have been conducted facing the real problems of data acquisition and control in the assembly, maintenance, and repair processes of aircraft. In this sense, the number of signals used simultaneously in historical tests has been determined to be a parameter that plays an important role in the analysis. This work is within the framework of a project that our working group of the Department of Electronic Technology has carried out together with the company Airbus Defense and Space (Airbus DS). Thus, all the analyses and researches for the different configurations of the test equipment have been validated for the company. Some state-of-the-art systems have been considered in the process of designing the structure of the test system while analyzing the main advantages and drawbacks. Every hardware or software component was identified and justified according to its importance with respect to the use case. A comparison of how every approach meets the requirements was taken into account to define a methodology for designing a portable and configurable ground testing system. Thus, the conclusions of our study are being used by Airbus DS for the design of a prototype for the next generation of AIMs in A400M.

A review on nanomaterial-based field effect transistor technology for biomarker detection.

Field effect transistor (FET) based sensors have attractive features such as small size, ease of mass production, high versatility and comparably low costs. Over the last decade, many FET type biosensors based on various nanomaterials (e.g. silicon nanowires, graphene, and transition metal dichalcogenides) have been developed to detect various classes of biomolecular targets due to their integration into portable and rapid test systems, both for use in the clinical lab and in point-of-care testing. This review (with 197 refs.)starts with an introduction into the specific features of FET biosensor technology. This is followed by a description of the essentials of methods for immobilization of recognition elements. The next section discusses the progress that has been made in FET based biosensors using semiconducting nanostructures composed of silicon, graphene, metal oxides, and transition metal dichalcogenides. A further section is devoted to microfluidic systems combined with FET biosensors. We then emphasize the biosensing applications of these diagnostic devices for analysis of clinically relevant biomarkers, specifically to sensing of neurotransmitters, metabolites, nucleic acids, proteins, cancer and cardiac biomarkers. Two tables are presented which summarize advances in applications of 1D and 2D nanomaterial-based FETs for biomarker sensing. A concluding section summarizes the current status, addresses current challenges, and gives perspective trends for the field. Graphical abstract Field effect transistor devices based on the use of1D and 2D semiconductor nanostructures (so called nano-FETs) are making use of materials including silicon nanowires, graphene, zinc oxide, indium oxide, titanium oxide, and molybdenum disulfidethat are further modified with recognition elements for biosensing application.

Design of a Portable Frame Integrality Testing System Based on SOPC

As there is no technology to detect the frame number area hidden weld rapidly and accurately, the frame integrality detection algorithm was studied in this paper. First of all, to achieve the conversion of longitudinal wave to transvers wave, the waveform transformation technology was applied to multiple thin and high impedance materials. The acoustic wedge was designed by using Plexiglas through 30 degree incident angle. Ultrasonic receiving and launch, signal acquisition and processing, display and alarm device were integrated using upper and lower structure based on the SOPC system of Niso II. This method showed that the instrument can accomplish the integrity of the frame detection rapidly, efficiently and accurately.

Research and development of sound quality in portable testing and evaluation system based on self-adaptive neural network

Ordinary microphone cannot accurately reflect authentic human feelings in the sound quality testing and evaluation. By contrast, professional artificial head system can produce similar results with human feelings through the simulation of human auditory system, but it is expensive and unable to occupy the driver's seat to record the vehicle sound. Here we design a portable system based on self-adaptive neural network (NN) which can obtain the result of sound quality evaluation similar with the artificial head. The system consists of binaural microphone, signal conditioning units (SCU), and mobile phone. Firstly, sound is perceived by binaural microphone, processed by SCU, and collected by mobile phone. Initial sound quality objective parameters are calculated after noise reduction for sound signals and then the accurate objective parameters can be obtained from the initial parameters through the trained NN model. To train the model, the portable system and the HEAD system are simultaneously used to collect sound sample as the input and output sample sets under different conditions. After the input samples are preprocessed, wavelet entropy eigenvalues based on the best tree wavelet packet analysis are calculated along with psychoacoustic parameters of all the samples. Finally, we obtain the combined feature vectors and successfully train the model. Checked by the practical data, the relative error of sound quality objective parameters produced by the NN model is less than 5% compared with the HEAD system, which conforms to general engineering requirements. This inexpensive and user-friendly portable system paves a new way in the sound quality testing and evaluation that are highly desirable for vehicle acoustical designs and improvements.

Development of a portable and sensitive blood serum test system using LED-based absorption photometry and pump-free microfluidic technology

We reported a novel integrated portable human blood system based on absorption photometry and microfluidic technology. A capillary pump for fluid control was embedded in microfluidic chip instead of heavy syringe pump. The analytes could automatically flow, mix and react in chip. It achieves long-term stability of hydrophilic microfluidic channel surface for rapid and sensitive detection. Herein, we detected three analytes from human blood, including triglyceride (TGL), albumin (ALB) and total protein (TP) which are very important for health examination. All components of this system including light-emitting diode (LED) light source, microfluidic chip, photodiode detector (PD), electronic circuit, Organic LED screen and memory card were fully integrated into a portable instrument with small size (11.2 × 7.2 × 6.1 cm). The pair of LED and PD was used for measuring light absorbance of biochemical assay. The limit of detections (LODs) for TGL, ALB and TP were estimated to be below 0.1 mmol/L, 4 g/L and 10 g/L respectively, which is significantly below the clinical cut-off value. Passing − Boblok regression analyses were used to achieve the evaluation for this system. It showed good accuracy and feasibility of our system and was expected to be useful as a potential clinical tool for human blood serum test.

Research on Reconfigurable Instrument Technology of Portable Test System of Missiles

To solve the problem of low test efficiency and weak maneuverability of missiles, the reconfigurable instrument technology of missiles’ portable test system is researched. In this paper, the realization plan based on PXI bus is proposed and key links of resource research is analyzed. Based on FPGA+DSP construction, the hardware circuit of the reconfigurable instrument is designed and the logic files are compiled. The research on the reconfigurable instrument technology can relieve the problem of low test efficiency and weak maneuverability of missiles effectively, and provide basis for further research of missiles’ portable test systems.

Evaluation of the accuracy of “ChE check mobile” in measurement of acetylcholinesterase in pesticide poisoning

Background: Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are used in clinical management to confirm the diagnosis and indicate the severity of organophosphorus and carbamate poisoning. ChE check mobile is a new portable cholinesterase testing system developed in Germany. The study aims to evaluate the accuracy of ChE check mobile compared to the standard reference method and Test-mate ChE system.Methods: Patients with organophosphorus and carbamate poisoning were recruited from two general hospitals in Sri Lanka between September 2013 and November 2014. The AChE was measured using the three methods.Results: Blood samples were collected from 185 self-poisoned patients (170 organophosphorus and 15 carbamate) and 20 normal individuals. ChE check mobile correlated well with spectrophotometer readings (Pearson’s correlation coefficient 0.87) but gave higher values (Mean bias for AChE: +6.55 (95% CI: −11 to 24) U/g Hb). A similar positive bias from Test-mate results was also observed. Applying a correction factor derived from the volunteer samples (dividing by 1.353) greatly improved agreement in pesticide poisoned patients.Conclusions: ChE check mobile system allowed for rapid determination of AChE activity but gave somewhat higher AChE compared to other methods. Applying a correction factor of 1.353 provide a good agreement to both reference and Test-mate ChE machine in this setting.

Portable Lorentz Force Eddy Current Testing System With Rotational Motion

In this paper, we investigate a new portable Lorentz force eddy current testing system using a diametrically magnetized cylindrical magnet rotating around its mass centroid axis. In order to compare the electromagnetic torque caused by the Lorentz force and the induced voltage generated by the secondary magnetic field, three different model approaches are considered: the weak reaction approach and the quasi-stationary approach as approximating approaches and the transient simulation as a reference one. The experimental results of the induced voltage in the coil surrounding the permanent magnet are compared with the results of the transient solution. In an additional simulation a possible imperfection of the real system and its influence is studied.

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A Novel Fluorometric Bio-Sensing-Based Arsenic Detection System for Groundwater

Arsenic that adversely affects human health is frequently reported in certain regions in India and other parts of the world. A low cost, portable, and eco-friendly field test system is required to monitor the levels of arsenic in drinking water procured from different tube wells and open wells. This paper presents the construction of biosensor strain by transforming E. coliDH $5\alpha $ with the plasmid pJSKV51 carrying in-frame promoter operator region as well as entire arsR gene, part of arsD gene and enhanced green fluorescent protein (EGFP) gene. This strain was able to induce EGFP in presence of arsenic III ion. This paper further presents a novel EGFP-based bio-electronic sensing methodology to develop a low-cost battery operated system to measure the fluorescence emitted by biosensor strain and display the numerical values of the concentrations of arsenic in water samples. In this method, a blue light of 480 nm excites the EGFP to produce a green fluorescence signal in proportion to arsenic concentration. The developed device includes a compact embedded system to measure the signal fluorescence using light sensor, programmable controllers and liquid crystal display to show the corresponding concentration of the arsenic in ppb. The experimental results show that the system can detect and display over a range from 5 to 100 ppb.

The Design of the Site Dynamic Balance Test System Based on ARM

The problem of the dynamic balance has always been a research hot spot. People hope to have faster processing speed, higher precision, more portable test system, to continuously improve the measurement system. This paper discusses the dynamic balancing test system design, including hardware and software two aspects. Through the hardware part, we can have the amplitude and the phase of the unbalanced component shown on the screen; through the software part, we can change the parameter freely to handle the different problem of the different rotor.

Evaluation of a Portable Haemoglobin Metre Performance in Children with Sickle Cell Disease and Implications for Healthcare in Resource-poor Settings

Sub-Saharan Africa has the largest burden and worst outcome of sickle cell disease (SCD). This gloomy outlook has been attributed to the lack of use of simple and cost-effective measures for diagnosis and treatment of the disease. Although haematology analysers are the gold standard for accurate measurement of haemoglobin (Hb) concentration, they are often out of reach of most health facilities in resource-poor settings, thus creating a care gap. We conducted this study to examine the agreement between a point-of-care device and haematology analyser for determining the Hb concentration in children with SCD and its usefulness in resource-poor settings. Ethylenediaminetetraacetic acid blood samples collected from participants were processed to estimate their Hb concentration using two devices (Sysmex KX21N haematology analyser and portable mission Hb device). The agreement between the two sets of measurements was assessed by the Bland and Altman method. The intraclass and concordance correlation coefficients were 0.854 and 0.936, respectively. Sensitivity and specificity were 84.2% and 98.6%, respectively. The positive and negative predictive values were 94.1% and 96.0%, respectively. The Bland and Altman's limit of agreement was -2.3 to 1.6 and the mean difference was -0.34 with non-significant variability between the two measurements (p = 0.949). Hb concentration determined by the portable testing system is comparable with that determined by the haematology analyser. We recommend its use as a point-of-care device for determining Hb concentration of SCD children in resource-poor settings where haematology analysers are not available.

Plasma endotoxin activity in kangaroos with oral necrobacillosis (lumpy jaw disease) using an automated handheld testing system.

The aim of the present study was to evaluate the reliability and effectiveness of directly determining endotoxin activity in plasma samples from kangaroos with lumpy jaw disease (LJD, n=15) and healthy controls (n=12). Prior to the present study, the ability of the commercially available automated handheld portable test system (PTSTM) to detect endotoxin activity in kangaroo plasma was compared with that of the traditional LAL-kinetic turbidimetric (KT) assay. Plasma samples, which were obtained from endotoxin-challenged cattle, were diluted 1:20 in endotoxin-free water and heated to 80°C for 10 min. The performance of the PTSTM was not significantly different from that of the traditional LAL-based assay. The data obtained using PTSTM correlated with those using KT (r2=0.963, P<0.001). These findings indicated that the PTSTM is applicable as a simplified system to assess endotoxin activity in macropods. In the present study, we demonstrated the diagnostic value of plasma endotoxin activity in kangaroos with systemic inflammation caused by oral necrobacillosis and identified plasma endotoxin activity as a sensitive marker of systemic inflammation in kangaroos with LJD. Based on ROC curves, we proposed a diagnostic cut-off point for endotoxin activity of >0.22 EU/ml for the identification of LJD. Our results indicate that the assessment of plasma endotoxin activity is a promising diagnostic tool for determining the outcome of LJD in captive macropods.

Arduino-based automation of a DNA extraction system.

There have been many studies to detect infectious diseases with the molecular genetic method. This study presents an automation process for a DNA extraction system based on microfluidics and magnetic bead, which is part of a portable molecular genetic test system. This DNA extraction system consists of a cartridge with chambers, syringes, four linear stepper actuators, and a rotary stepper actuator. The actuators provide a sequence of steps in the DNA extraction process, such as transporting, mixing, and washing for the gene specimen, magnetic bead, and reagent solutions. The proposed automation system consists of a PC-based host application and an Arduino-based controller. The host application compiles a G code sequence file and interfaces with the controller to execute the compiled sequence. The controller executes stepper motor axis motion, time delay, and input-output manipulation. It drives the stepper motor with an open library, which provides a smooth linear acceleration profile. The controller also provides a homing sequence to establish the motor's reference position, and hard limit checking to prevent any over-travelling. The proposed system was implemented and its functionality was investigated, especially regarding positioning accuracy and velocity profile.

Portable Microfluidic System for Rapid Genetic Testing

SUMMARYPolymerase chain reaction (PCR) is a key technology of genetic testing, but the long thermal cycling time has been a problem in achieving rapid diagnosis of pathogenic organisms and cancer. We describe a simple, portable, and rapid genetic testing system based on ultrafast segment flow and fluorescent detection. In particular, we improved the flow‐through PCR to accelerate the thermal cycling time and simplify the operation for practical use. The PCR solution was injected in a small volume of about several microliters by an air syringe, and flowed as segment flow. The segment of PCR solution was moved in a serpentine microchannel on a microfluidic device over two temperature zones for denaturation and annealing/extension reactions. The base plate formed upon the serpentine microchannel pattern was made of cyclo‐olefin polymer (COP) and covered with a thin transparent film. Furthermore, a specialized portable system was developed for the microfluidic device of a segment‐flow PCR. Heater units, a syringe pump, a fluorescence detector, and PC were integrated in a suitcase for portable use. Using this portable system, a microorganism modeling anthrax and a point mutation of FGFR3 gene were successfully detected within 6.5 min.

Eye Vision Testing System and Eyewear Using Micromachines

Proposed is a novel eye vision testing system based on micromachines that uses micro-optic, micromechanic, and microelectronic technologies. The micromachines include a programmable micro-optic lens and aperture control devices, pico-projectors, Radio Frequency (RF), optical wireless communication and control links, and energy harvesting and storage devices with remote wireless energy transfer capabilities. The portable lightweight system can measure eye refractive powers, optimize light conditions for the eye under testing, conduct color-blindness tests, and implement eye strain relief and eye muscle exercises via time sequenced imaging. A basic eye vision test system is built in the laboratory for near-sighted (myopic) vision spherical lens refractive error correction. Refractive error corrections from zero up to −5.0 Diopters and −2.0 Diopters are experimentally demonstrated using the Electronic-Lens (E-Lens) and aperture control methods, respectively. The proposed portable eye vision test system is suited for children’s eye tests and developing world eye centers where technical expertise may be limited. Design of a novel low-cost human vision corrective eyewear is also presented based on the proposed aperture control concept. Given its simplistic and economical design, significant impact can be created for humans with vision problems in the under-developed world.

Detecting endotoxin activity in raw milk using an automated testing system

Gram-negative bacteria are among the most common environmental pathogens causing mastitis. Endotoxin plays a major role in the pathophysiology of gram-negative bacterial sepsis; therefore, attempts have been made to detect and quantify it, with conflicting findings, in various states of infection. The simple and easy portable test system (PTS) for endotoxin activity offers several advantages over the traditional microplate kinetic limulus amebocyte lysate (LAL)-based test used by diagnostic laboratories. It is small, inexpensive and portable, requires only small quantities of raw milk, and provides results relatively rapidly in comparison to traditional methods. Thus the portability and ready availability of this cartridge system adds to its attractiveness for use in acute coliform mastitis (ACM). However, since the results obtained using this portable test will often dictate the course of clinical care and hygiene management, it is important that the cartridge system provides accurate information. The aim of the present study was to compare endotoxin activities detected in raw milk samples obtained from healthy dairy cattle without mastitis by a commercially available PTS™ and traditional microplate LAL-based assay, which determined activities using a kinetic turbidimetric (KT) assay.

Development and Validation of a Portable Human Body Joint Power Test System

A portable human body joint power test system was developed using inertial sensor technology and wireless Bluetooth acquisition technology. A detailed description of the internal structure of the system and the data processing method involved is provided. The test system uses the cubic spline interpolation method, which is very convenient for obtaining the maximum peak points of muscle isotonic contraction joint power curves under different loads. Moreover, the system is portable and can be deployed in the classroom and the playground for education and testing. The test system is very useful in many respects, such as athlete selection and daily strength training. We established a model of our subject using a balanced proportion scaling method in the inverse dynamics software AnyBody modeling system. The muscle model uses the Hill muscle model. The data import interface program was written in the parameterized model definition language AnyScript to import data. The raw data was smoothed with a Butterworth low-pass filter. Dumbbell curl simulation was conducted in AnyBody. The results of the simulation and those of the real test system were tested using the paired samples t-test method; the value of Sig was determined to be greater than 0.05, indicating no significant difference and that the data of the test system are valid.

Portable surface stress biosensor test system based on ZigBee technology for health care

The paper presents a portable surface stress biosensor test system based on ZigBee technology for health care, which consists of a biosensor chip and an electronic test platform. The biosensor chip is a micro-scale and label-free polydimethylsiloxane micromembrane capacitive surface stress sensor. This chip consists of two micromembranes, in which one acts as the active unit and the other as reference. The signal difference of active and reference is acquired with the aid of capacitive detection circuit, which has high signal-to-noise ratio and speedy electrical readout. The electronic test platform is designed based on ZigBee technology to realize the accurate detection of small capacitance and the wireless signal transmission. The capacitive resolution of the system is 0.1 fF (femtofarad). The capacitance measured by the system is diminished and exaggerated with the increase and decrease of ethanol volume, which is corresponding to the capacitive formula. The haemoglobin test results from the system are consistent with the theoretical analysis and the test results from Agilent B1500A, which demonstrates that the system can be considered as a measurer of haemoglobin for clinical applications. The experiments also illustrate that the biosensor test system has good stability and multiplicity.