The biological acoustic sensor to record the interactions of the microbial cells with the phage antibodies in conducting suspensions

Recombinant antibodies by phage display for bioanalytical applications

Antibody phage display, aimed at preparing antibodies to defined antigens, is a useful replacement for hybridoma technology. The phage system replaces all work stages that follow animal immunization with simple procedures for manipulating DNA and bacteria. It enables the time needed to generate stable antibody-producing clones to be shortened considerably, making the process noticeably cheaper. Antibodies prepared by phage display undergo several affinity selection steps and can be used as selective receptors in biosensors. This article briefly describes the techniques used in the making of phage antibodies to various antigens. The possibilities and prospects are discussed of using phage antibodies as selective agents in analytical systems, including biosensors.

Inkjet Printing of Plate Acoustic Wave Devices

In the paper, the results of production of Ag inkjet printed interdigital transducers to the acoustic delay line based on Y-cut X-propagation direction of lithium niobate plate for the frequency range from 1 to 14 MHz are presented. Additionally, morphological, structural, and electro-physical characteristics of the obtained electrodes were investigated. Mathematical modeling of the excitation of acoustic waves by these electrode structures was carried out. Comparison of the theoretical results with experimental ones showed their qualitative and quantitative coincidences. It was shown that conventional inkjet printing can replace the complex photolithographic method for production of interdigital transducers for acoustic delay lines working up to 14 MHz. The resulting electrode structures make it possible to efficiently excite acoustic waves with a high value of electromechanical coupling coefficient in piezoelectric plates.

Research Progress of M13 Bacteriophage-Based Biosensors

Recently, new virus-based sensor systems that operate on M13 bacteriophage infrastructure have attracted considerable attention. These systems can detect a range of chemicals with excellent sensitivity and selectivity. Filaments consistent with M13 bacteriophages can be ordered by highly established forms of self-assembly. This allows M13 bacteriophages to build a homogeneous distribution and infiltrate the network structure of nanostructures under mild conditions. Phage display, involving the genetic engineering of M13 bacteriophages, is another strong feature of the M13 bacteriophage as a functional building block. The numerous genetic modification possibilities of M13 bacteriophages are clearly the key features, and far more applications are envisaged. This paper reviews the recent progress in the application of the M13 bacteriophage self-assembly structures through to sensor systems and discusses future M13 bacteriophage technology.

Use of an electro-optical sensor and phage antibodies for immunodetection of Herbaspirillum

A sheep single-chain antibody-fragment library (Griffin.1, UK) was used to obtain miniantibodies to the lipopolysaccharide of Herbaspirillum seropedicae Z78. Using electro-optical analysis and electron microscopy, we recorded a biospecific interaction of antigenic determinants on the cell surface with phage antibodies against the LPS of H. seropedicae Z78 (mini-Abs_LPS). Control experiments were run to rule out nonspecific binding of the mini-Abs_LPS to cells of Azospirillum brasilense Sp245. Use of the highly specific mini-Abs_LPS enabled the lipopolysaccharide of H. seropedicae Z78 to be detected in a mixture of bacterial cells by electro-optical means (analysis time, ∼5 min). This report is the first to show the possibility of rapid detection of Herbaspirillum on the basis of electro-optical analysis coupled with the use of mini-Abs_LPS. The results are promising for the development of biosensor-based methods to detect potentially human-harmful prokaryotes whose structures either have not been studied or are absent from commercial databases.