Label-free optical antibody testing kit based on a self-assembled whispering-gallery-mode microsphere

The appearance of antibodies in blood is a critical signal to suggest the infection. A rapid and accurate detection method for the antibody is significant to the disease diagnosis, especially for the epidemic. To this end, a highly sensitive whispering-gallery-mode (WGM) optical testing kit is designed and fabricated for detecting the specific immunoglobulin antibodies. The key component of the kit is a silica self-assembled microsphere decorated with the nucleocapsid proteins (N-proteins) of the SARS-CoV-2 virus. After the N-protein antibody immunoglobulin G (N-IgG) and immunoglobulin M (N-IgM) solutions being injected into the kit, the WGM red-shifts due to the antigen–antibody reaction. The wavelength displacement rates are proportional to the concentrations of these two antibodies from 1 to 100 μg/mL. A good specificity of the kit is demonstrated by the nonspecific human immunoglobulin G (H-IgG) and immunoglobulin M (H-IgM).     

An artificial neural network for biomass estimation from automatic pH control signal

This study developed an artificial neural network (ANN) to estimate the growth of microorganisms during a fermentation process. The ANN relies solely on the cumulative consumption of alkali and the buffer capacity, which were measured on-line from the on/off control signal and pH values through automatic pH control. The two input variables were monitored on-line from a series of different batch cultivations and used to train the ANN to estimate biomass. The ANN was refined by optimizing the network structure and by adopting various algorithms for its training. The software estimator successfully generated growth profiles that showed good agreement with the measured biomass of separate batch cultures carried out between at 25 and 35_C.     

Implantable self‐aligning fiber‐optic optomechanical devices for in vivo intraocular pressure‐sensing in artificial cornea

Artificial cornea is an effective treatment of corneal blindness. Yet, intraocular pressure (IOP) measurements for glaucoma monitoring remain an urgent unmet need. Here, we present the integration of a fiber‐optic Fabry‐Perot pressure sensor with an FDA‐approved keratoprosthesis for real‐time IOP measurements using a novel strategy based on optical‐path self‐alignment with micromagnets. Additionally, an alternative noncontact sensor‐interrogation approach is demonstrated using a bench‐top optical coherence tomography system. We show stable pressure readings with low baseline drift (<2.8 mm Hg) for >4.5 years in vitro and efficacy in IOP interrogation in vivo using fiber‐optic self‐alignment, with good initial agreement with the actual IOP. Subsequently, IOP drift in vivo was due to retroprosthetic membrane (RPM) formation on the sensor secondary to surgical inflammation (more severe in the current pro‐fibrotic rabbit model). This study paves the way for clinical adaptation of optical pressure sensors with ocular implants, highlighting the importance of controlling RPM in clinical adaptation.     

A low‐cost,computer‐controlled robotic flower system for behavioral experiments

Human observations during behavioral studies are expensive, time‐consuming, and error prone. For this reason, automatization of experiments is highly desirable, as it reduces the risk of human errors and workload. The robotic system we developed is simple and cheap to build and handles feeding and data collection automatically. The system was built using mostly off‐the‐shelf components and has a novel feeding mechanism that uses servos to perform refill operations. We used the robotic system in two separate behavioral studies with bumblebees (Bombus terrestris): The system was used both for training of the bees and for the experimental data collection. The robotic system was reliable, with no flight in our studies failing due to a technical malfunction. The data recorded were easy to apply for further analysis. The software and the hardware design are open source. The development of cheap open‐source prototyping platforms during the recent years has opened up many possibilities in designing of experiments. Automatization not only reduces workload, but also potentially allows experimental designs never done before, such as dynamic experiments, where the system responds to, for example, learning of the animal. We present a complete system with hardware and software, and it can be used as such in various experiments requiring feeders and collection of visitation data. Use of the system is not limited to any particular experimental setup or even species.     

A synaptic temperature sensor for body cooling

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Intrinsic fluorescence‐based at situ soft sensor for monitoring monoclonal antibody aggregation

Intrinsic fluorescence spectroscopy, in conjunction with partial least squares regression (PLSR), was investigated as a potential technique for online quality control and quantitative monitoring of Immunoglobulin G (IgG) aggregation that occurs following exposure to conditions that emulate those that can occur during protein downstream processing. Initially, the impact of three stress factors (temperature, pH, and protein concentration) on the degree of aggregation determined using size exclusion chromatography data, was investigated by performing a central composite designexperiment and applying a fitting response surface model. This investigation identified the influence of the factors as well as the operating regions with minimum propensity to induce protein aggregation. Spectral changes pertinent to the stressed samples were also investigated and found to corroborate the high sensitivity of the intrinsic fluorescence to conformational changes of the proteins under study. Ultimately, partial least squares regression was implemented to formulate two fluorescence‐based soft sensors for quality control—product classification—and quantitative monitoring—concentration of monomer. The resulting regression models exhibited accurate prediction ability and good potential for in situ monitoring of monoclonal antibody downstream purification processes. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1423–1432, 2015     

Evolutionary plasticity in the requirement for force exerted by ligand endocytosis to activate C. elegans Notch proteins

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A dissolved oxygen sensor based on composite fluorinated xerogel doped with platinum porphyrin dye

A new functional fluorinated material taking n‐propyltrimethoxysilicane (n‐propyl‐TriMOS) and 3,3,3‐trifluoropropyltrimethoxysilicane (TFP‐TriMOS) as precursors was applied to construct a novel dissolved oxygen sensing film. The sensing film was fabricated by dip‐coating the functional fluorinated material‐doped [meso‐tetrakis(pentafluorophenyl) porphyinato] platinum(II) (PtF₂₀TPP) onto a glass slide. The oxygen sensing film exhibited a good linear relationship, fast response time, long stability and high sensitivity to dissolved oxygen. In the developed optical oxygen sensor, an LED and a photodiode were composed to construct a back‐detection optical system not needing an optical fiber based on fluorescence intensity detection. The smart optical oxygen sensor based on the PtF₂₀TPP fluorescence quenching possesses the advantages of portability and low cost and can be applied to the dissolved oxygen in situ monitoring in seawater. Copyright © 2009 John Wiley & Sons, Ltd.     

Prolonged mitosis causes separase deregulation and chromosome nondisjunction

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Human cells experience a Zn2+ pulse in early G1

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