The antigen-antibody interaction was detected and quantified by electrochemical impedance spectroscopy (EIS). selleck compound The resultant device showed a linear dynamic range of anti-GPI antibodies in serum ranging from 1.0 to 10.0 IU mL-1, with a limit of detection of 0.31 IU mL-1. This method also holds great potential for the detection of IgG antibodies related to other multiple medical conditions characterized by overexpression of antibodies.Simultaneous detection of various intracellular biomarkers is promising for early diagnosis and treatment of cancer. Herein, a split primer ligation-triggered catalyzed hairpin assembly-based on dual-signal electrochemical biosensor was constructed for the determination of two pairs of cancer mRNAs TK1 and c-myc, survivin and GalNAc-T by using ferrocene molecular beacon and hemin molecular beacon as detection signal sources. Each pair of targets exists simultaneously, can release the split primers and ligated as the integral primers, hybridization occurred between the integral primers and part of MBs, causing a double-stranded DNA formed. The probes hybridized with the unfolded MBs and displaced integral primers. Finally, the displaced integral primers again hybridized with the MBs and initiated cycle amplification. Under the optimal conditions, the detection limit of TK1 and c-myc mRNA is as low as 0.022 nM, and that of survivin and GalNAc-T mRNA is 0.029 nM. In addition, two pairs of cancer mRNAs could act as outputs to activate an AND logic gate.On-site detection of substance abuse is an important approach in the preventive and intervention protocols implementations. It is known that the traditional methods are heavy, time-consuming, and need a high level of logistical requirements. As such, biosensors represent great potential to simplify and improve substance abuse detection. In this study, we have designed a functionalized screen-printed electrode (SPE) electrochemical biosensor with cobalt oxide nanoparticles and single-chain antibody fragments (scFvs) for cocaine detection. Different electrochemical techniques such as differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectrometry were used to examine the functionality of the designed biosensor. Furthermore, SEM observations were performed to observe the surface changes after functionalization. The results showed that the linearity ranged between 5.0 and 250 ng/mL and a detection limit of 3.6 ng/mL (n = 6). These results were compared to results obtained from Q-TOF/MS where four different matrices (serum, sweat, urine, and saliva) were spiked with 100 ng/mL cocaine and were analyzed by both methods (Biosensor and Q-TOF/MS). Results showed a higher performance of the biosensor compared to traditional methods. In addition, the selectivity of the biosensor was shown in the presence of different interferents where the designed platform showed a specific response to only cocaine. In conclusion, the designed biosensor proposes great potential for portable and on-site substance abuse detection in addition to boasting the capability of reuse of the SPE and thus, reducing the costs related to such applications.A rapid highly sensitive genosensor has been developed for monitoring the presence of Legionella spp. in different water systems (domestic hot water, heating/cooling systems or cooling towers) in order to avoid its spreading from the source of contamination. The genosensor integrates a loop mediated isothermal amplification (LAMP) reaction with an electrochemical transduction signal, producing a very simple, rapid to perform and cost effective method, suitable for in situ analyses. This approach detects as low as 10 fg of Legionella nucleic acid, corresponding to only 2 number copies of the bacteria. The use of an electrochemical redox-active double stranded DNA (dsDNA) intercalating molecule, known as methylen blue (MB), allows the immediate electrochemical reading during the DNA polymerization. The sensor can obtain quantitative results in 20 min with a correlation between the electrochemical data and Legionella spp. copy number (at a logarithmic scale) of r = -0.97. In conclusion, a fast, easy to use, and accurate electrochemical genosensor, with high precision, sensitivity, and specificity has been developed for in situ detection of Legionella spp. enabling real time decision making and improving significantly the current detection methods for the prevention and screening of Legionella.Sulfur-containing species are essential in the composition and the metabolism of the organisms, thus developing a full set of implements to cover all of them is still a favorable choice. Herein, we chose imidazo [1,5-α]pyridine moiety as the basic fluorophore for the detection of sulfite, and preliminarily completed the toolset since biothiols (GSH, Cys, Hcy), H2S, and PhSH could be detected by sensors based on the same backbone. The designed sensor, IPD-SFT, with structural novelty and large Stokes shift (130 nm), indicated the most attractive advantages of remarkably rapid response period (within 1 min) and high selectivity for sulfite from all the sulfur-containing species. Other practical properties included high sensitivity (LOD = 50 nM) and wide pH adaptability (5.0-11.0). Furthermore, IPD-SFT could monitor both exogenous and endogenous sulfite. It not only raised a potential tool for sulfite detection, but also preliminarily completed the toolset for all the sulfur-containing species. The development of such toolsets might reveal the sulfur-containing metabolism and corresponding physiology and pathological procedures.We developed a simple approach to form picoliter to nanoliter monodisperse droplets by controlling the interface of an asymmetrical beveled capillary (ABC), with minimalist device of a beveled capillary and a liquid driving module without the need of additional equipment or external forces. We observed an evident leap decrease effect in droplet size specially existed in a capillary with a beveled outlet interface instead of a conventional flat capillary within proper bevel angle and flow rate range, by which droplets with diameters of 2-5 times the inner diameter of the capillary could be spontaneously generated by surface tension. A preliminary theoretical explanation is given to the mechanism of droplet formation at the capillary beveled interface. Various factors affecting the droplet generation process were studied, including capillary hydrophilicity, bevel angle, beveled outlet size, and inner diameter of the capillary, and dispersed phase flow rate. In the optimized condition range, good linear relationship between the droplet volume and the capillary inner diameter (10-100 μm) were obtained, which could be used to conveniently adjust the droplet volume with an adjustable droplet volume range up to 1000 times.