Application of PCDA/SPH/CHO/Lysine vesicles to detect pathogenic bacteria in chicken

Recent Advances in Colorimetric Tests for the Detection of Infectious Diseases and Antimicrobial Resistance

Diagnosis of infection-causing microorganisms with sensitive, rapid, selective and economical diagnostic tests is critical to start the right treatment. With these tests, the spread of infections can be prevented. In addition to that, the detection of antimicrobial resistance also makes a significant contribution to public health. In recent years, different types of diagnostic tests have been developed as alternatives to traditional diagnostic tests used in clinics. In particular, colorimetric tests, which minimize the need for an instrument, have advantages owing to their cost effectiveness, rapid response and naked-eye detection and practical use. In this review, we especially focused on pH indicators and nanomaterial-based colorimetric tests in detection of infection-causing microorganisms and antimicrobial resistance.

Thermochromic Polymeric Films for Applications in Active Intelligent Packaging-An Overview

The need for passive sensors to monitor changes in temperature has been critical in several packaging related applications. Most of these applications involve the use of bar codes, inks and equipment that involve constant complex electronic manipulation. The objective of this paper is to explore solutions to temperature measurements that not only provide product information but also the condition of the product in real time, specifically shelf-life. The study will explore previously proposed solutions as well as plans for modified approaches that involve the use of smart polymers as temperature sensors.

Alkali Metal Salts of 10,12-Pentacosadiynoic Acid and Their Dosimetry Applications

Wide-dose-range 2D radiochromic films for radiotherapy, such as GAFchromic EBT, are based on the lithium salt of 10,12-pentacosadiynoic acid (Li-PCDA) as the photosensitive component. We show that there are two solid forms of Li-PCDA-a monohydrated form A and an anhydrous form B. The form used in commercial GAFchromic films is form A due to its short needle-shaped crystals, which provide favorable coating properties. Form B provides an enhanced photoresponse compared to that of form A, but adopts a long needle crystal morphology, which is difficult to process. The two forms were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, CP-MAS ¹³C solid-state NMR spectroscopy, and thermogravimetric analysis. In sum, these data suggest a chelating bridging bidentate coordination mode for the lithium ions. The sodium salt of PCDA (Na-PCDA) is also reported, which is an ionic cocrystal with a formula of Na⁺PCDA^-·3PCDA. The PCDA and PCDA^- ligands display monodentate and bridging bidentate coordination to the sodium ion in contrast to the coordination sphere of the Li-PCDA forms. In contrast to its lithium analogues, Na-PCDA is photostable.

Recent Trends in Nanomaterials-Based Colorimetric Detection of Pathogenic Bacteria and Viruses

Rapid, sensitive, selective, convenient, and cost-effective pathogen diagnosis is important to prevent further spread of pandemic diseases, minimize social and economic losses, and to facilitate right clinical therapy. Over the past few years, various sensor-based diagnostic systems outperforming conventional pathogenic diagnostic assays have been developed. Among them, colorimetric biosensors detecting target molecules by the naked eye have attracted much attention due to their simplicity, practicality, and cost-effectiveness. Recently, nanomaterials have been adopted as a versatile signal transduction and amplification tool for rapid and sensitive detection of pathogenic bacteria and viruses. Here, recent trends and advances are reviewed in detecting and diagnosing pathogenic bacteria and viruses using colorimetric biosensors employing various nanomaterials. In addition, it is discussed how nanomaterials and bioreceptors can be better integrated together to develop rapid and sensitive colorimetric detection system in the future.

Responsive Polydiacetylene Vesicles for Biosensing Microorganisms

Polydiacetylene (PDA) inserted in films or in vesicles has received increasing attention due to its property to undergo a blue-to-red colorimetric transition along with a change from non-fluorescent to fluorescent upon application of various stimuli. In this review paper, the principle for the detection of various microorganisms (bacteria, directly detected or detected through the emitted toxins or through their DNA, and viruses) and of antibacterial and antiviral peptides based on these responsive PDA vesicles are detailed. The analytical performances obtained, when vesicles are in suspension or immobilized, are given and compared to those of the responsive vesicles mainly based on the vesicle encapsulation method. Many future challenges are then discussed.