Matzen Barber (braseason7)
es, Paramixoviruses, Arenaviruses and Herpesviruses. We describe the rationale for, immunologic mechanisms involved in, and design of viral vectored gene vaccines under development and discuss the potential utility of these novel genetic vaccine approaches in eliciting protection against infectious diseases and cancer.The development of novel high-sensitivity DNA-based biosensors is beneficial, as these devices have applications in the identification of genetic risk factors, medical diagnostics, and environmental monitoring. Herein, we report on the first robust device capable of detecting DNA on a microliter drop with a zepto-molar (10-21) concentration. To accomplish this, we engineered an electrical-electrochemical vertical device (EEVD) that comprises a novel drain and source terminal in a short-circuited configuration, paired with an ideal non-polarizable reference electrode. Vertical electron transfer occurs perpendicularly to the graphene plane, while the electronic current flows through the graphene van der Waals (vdW) heterojunctions. Ferrocene adsorbed on graphene was strategically chosen as the vdW heterojunction redox component. Charge carrier insertion into the graphene makes the EEVD 10 times more sensitive than traditional graphene field-effect transistors. Interfacial potential changes were measured for single-stranded DNA detection with an unprecedented zepto-molar limit of detection.A new immunoprobe, which can initiate the sedimentation of Ag nanoparticles (NPs) on an electrode surface, was developed for the electrochemical detection of carbohydrate antigen 72-4 (CA 72-4). To design the immunoprobe, zeolitic imidazolate frameworks (ZIFs) were employed as the carrier to enrich thionine molecules, then bovine serum albumin (BSA) was modified on the electrode surface. Advantageously, BSA, served as an anchor to further attach the labeling antibodies (Ab2) and alkaline phosphatase (ALP) to also be modified on the surface through covalent bonding. To construct the immunosensor, multiwalled carbon nanotube-graphene oxide composites were employed to provide active sites, and the electrodeposited Au NPs were used to immobilize coating antibodies. In the presence of CA 72-4, a sandwich immunosensor was established, and a cascade reaction was initiated to deposit Ag NPs under the catalysis, which can further improve the conductivity of electrode interface. Under the optimal conditions, the immunosensor displayed excellent performance with a wide linear range from 1 μU mL-1 to 10 U mL-1 and an ultralow detection limit of 0.438 μU mL-1 (S/N = 3).The simultaneous detection of multiple mycotoxins in grains is significant due to the enhanced toxicity induced by their synergistic effects. In this work, a dual-ratiometric electrochemical aptasensing strategy for the simultaneous detection of aflatoxin B1 (AFB1) and ochratoxin A (OTA) was developed. Here, an anthraquinone-2-carboxylic acid (AQ)-labelled complementary DNA (cDNA) was used to provide separate and specific binding sites to assemble the ferrocene-labelled AFB1 aptamer (Fc-Apt1) and methylene blue-labelled OTA aptamer (MB-Apt2). The target-induced current ratios of IFc/IAQ and IMB/IAQ were then used to quantitatively relate to AFB1 and OTA, respectively. Following this principle, two types of aptasensors involving the hairpin DNA (hDNA) and linear single-stranded DNA (ssDNA) as the cDNA were fabricated for performance comparisons. The results revealed that hairpin DNA with a rigid 2D structure can greatly improve the assembly and recognition efficiency of the sensing interface, which makes the hDNA-based aptasensor possess high sensitivity, reliability and anti-interference ability. buy Gossypol The hDNA-based aptasensor exhibited a detection range of 10-3000 pg mL-1 for AFB1 and 30-10000 pg mL-1 for OTA, respectively, with no observable cross-reactivity. Furthermore, the aptasensor was applied to analyze corn and wheat samples, and the reliability was validate
