Multifunctional Detection Research Articles

Multiscattering-enhanced optical biosensor: multiplexed, non-invasive and continuous measurements of cellular processes.

The continuous measurement of uptake or release of biomarkers provides invaluable information for understanding and monitoring the metabolism of cells. In this work, a multiscattering-enhanced optical biosensor for the multiplexed, non-invasive, and continuous detection of hydrogen peroxide (H2O2), lactate and glucose is presented. The sensing scheme is based on optical monitoring of the oxidation state of the metalloprotein cytochrome c (cyt c). The analyte of interest is enzymatically converted into H2O2 leading to an oxidation of the cyt c. Contact microspotting is used to prepare nanoliter-sized sensing spots containing either pure cyt c, a mixture of cyt c with glucose oxidase (GOx) to detect glucose, or a mixture of cyt c with lactate oxidase (LOx) to detect lactate. The sensing spots are embedded in a multiscattering porous medium that enhances the optical signal. We achieve limits of detection down to 240 nM and 110 nM for lactate and glucose, respectively. A microfluidic embodiment enables multiplexed and crosstalk-free experiments on living organisms. As an example, we study the uptake of exogenously supplied glucose by the green algae Chlamydomonas reinhardtii and simultaneously monitor the stress-related generation of H2O2. This multifunctional detection scheme provides a powerful tool to study biochemical processes at cellular level.

A peptide-based fluorescent chemosensor for multianalyte detection.

A novel multifunctional peptide fluorescent chemosensor (DP-3) with a lysine backbone and double sides conjugated with histidine and dansyl groups has been designed and synthesized by solid phase synthesis. This chemosensor is a promising analytical tool for detecting Zn(2+), Cu(2+), and S(2-) based on different mechanisms in 100% aqueous solutions, and intracellular biosensing has been successfully actualized. The peptide beacon structure of DP-3 makes it more stable and capable of achieving multianalyte detection, especially for sulfide ions. Until now, there have been few examples of using a peptide fluorescent chemosensor to detect anions with a continuous method. As designed, DP-3 exhibits excellent cell permeation and low biotoxicity and displays high selectivity and sensitivity, with Zn(2+) and Cu(2+) detection limits of 82 nM and 78 nM, respectively. This study raises the new possibility of a highly selective peptide fluorescent chemosensor for multifunctional detection, including cation and anions, by different mechanisms in environmental and biological systems. We expect that this work will inspire the development of a multifunctional beacon peptide-based fluorescent chemosensor library using modifiable lateral and terminal groups for a variety of practical applications in physiological and pathological events.

Research on the Virtual Prototype of Multifunction Filter Material Detection Device

This paper introduces the characteristics and working principle of multifunctional filter material detection device, The design of detection device filter, Can be assembled and disassembled quickly, By the combination of different height of the supporting cylinder, Can adapt to the changes of different thickness of Filter layer, Device can realize the performance of filter material under different conditions, The application of a detection scheme is illustrated by an example. Based on the way of parametric design with SolidWorks, Reasonable modeling ideas are put forward, Combined with the instance, Completed the multifunctional filter material detection device prototype of virtual design, the method can effectively improve design efficiency, For the similar product design provides a new way of thinking

A proteorhodopsin-based biohybrid light-powering pH sensor

The biohybrid sensor is an emerging technique for multi-functional detection that utilizes the instinctive responses or interactions of biomolecules. We develop a biohybrid pH sensor by taking advantage of the pH-dependent photoelectric characteristics of proteorhodopsin (pR). The transient absorption kinetics study indicates that the photoelectric behavior of pR is attributed to the varying lifetime of the M intermediate at different environmental pH values. This pR-based biohybrid light-powering sensor with microfluidic design can achieve real-time pH detection with quick response and high sensitivity. The results of this work would shed light on pR and its potential applications.

An Optical Fiber Sensor for Remote pH Sensing and Imaging

A fiber-optical probe for pH sensing and real-time imaging is successfully fabricated by connecting a polymer imaging fiber and a gradient index (GRIN) lens rod which was modified with a sensing film. By employing an improved metallographic microscope, an optical system is designed to cooperate with the probe. This novel technique has high-quality imaging capabilities for observing remote samples while measuring pH. The linear range of the probe is pH 1.2-3.5. This technique overcomes the difficulty that high-quality images cannot be obtained when directly using conventional imaging bundles for pH sensing and imaging. As preliminary applications, the corrosion behavior of an iron screw and the reaction process of rust were investigated in buffer solutions of pH 2.0 and 2.9, respectively. The experiment demonstrated that the pH values of the analytes' surface were higher than that of buffer solutions due to the chemical reaction. It provides great potential for applications in optical multifunctional detection, especially in chemical sensing and biosensing.

Independent multifunctional detection by wettability controlled inverse opal hydrogels

Utilizing the wettability of inverse opal hydrogels, we report a new strategy to construct photonic hydrogels with multiple types of reliable signals, such as non-wetting (transparent), image contrast (weak color) with shifts of diffraction maximum (bright color), developing optical sensors for multifunctional detection.

Development of a Wireless Love Wave Biosensor Platform for Multi-functional Detection

Development of a Wireless Love Wave Biosensor Platform for Multi-functional Detection

Development of a Wireless Love Wave Biosensor Platform for Multi-functional Detection

A Love wave-based biosensor with a 440 MHz operating frequency was developed for simultaneous detection of two different concentrations of anti-dinitrophenyl-keyhole limpet hemocyanin (Anti-DNP-KLH) rabbit immunoglobulin G (IgG) in a single sensor. The sensor was composed of surface acoustic wave (SAW) reflective delay lines built from interdigital transducer (IDT) and several reflectors, a poly(methyl methacrylate) (PMMA) waveguide layer, and two sensitive films. To extract optimal device parameters, coupling of mode (COM) modeling was carried. According to the device parameters determined, the Love wave biosensor was fabricated and then wirelessly characterized by a network analyzer. Binding of anti-DNP IgG to DNP induced a change in the time positions of the original reflection peaks mainly due to the mass loading effect. The measured time positions were matched well with the predicted values from COM modeling. The sensitivities evaluated from the first and second sensitive films were 167.9 and 44.8 deg·µg-1·ml-1, respectively.

Simultaneous LIF and retro‐reflected beam interference detection for CE

This Short Communication describes a novel optical detection method for CE, based on the combination of LIF detection and retro-reflected beam interference detection. By the use of a side-illuminated laser beam, an on-column multifunctional detection for CE has been developed, and some key elements in the scheme have been optimized. In addition, two miscellaneous samples including fluorescent dyes, carbohydrates and amino acids have been determined to evaluate its performance. Without any additional pretreatment, sufficient LOD and linear ranges have been achieved for most analytes. Its performance in retro-reflected beam interference detection is better than those mentioned in a former report, and its fluorescent sensitivity is comparable with the achievable sensitivity by conventional LIF systems, all of which together combine high sensitivity and universal analysis to a certain extent.

Nanotechnology for cancer diagnostics: promises and challenges

Despite recent progress in the treatment of cancer, the majority of cases are still diagnosed only after tumors have metastasized, leaving the patient with a grim prognosis. However, there may be an opportunity to drastically reduce the burden of cancer, if the disease can be detected early enough. Nanotechnology is in a unique position to transform cancer diagnostics and to produce a new generation of biosensors and medical imaging techniques with higher sensitivity and precision of recognition. This review examines the in vitro and in vivo diagnostic applications of nanoparticles, and other nanodevices that are likely to have an impact on the field in the future. Future developments that may lead to the realization of multifunctional detection and treatment nanoparticle platforms are also discussed.