Ultrasensitive detection of aromatic water pollutants through protein immobilization driven organic electrochemical transistors.

Xenobiotic aromatic water pollutants pose an extreme threat to environmental sustainability. Due to the lack of detectable functional groups in these compounds and scarcity of selective bio-recognition scaffolds, easy-to-use sensing strategies capable of on-site detection remain unavailable. Herein, to address this lacune, we entail a strategy that combines biosensor scaffolds with organic electronics to create a compact device for environmental aromatic pollution monitoring. As proof of principle, a sensor module capable of rapid, economic, reliable, and ultrasensitive detection of phenol down to 2 ppb (0.02 µM) was designed wherein biosensing protein MopR was coupled with an organic electrochemical transistor (OECT). For effective interfacing of the sensing scaffold MopR, graphene oxide (GO) nanosheets were optimized as a host immobilization matrix. The MopR-GO immobilized sensor module was subsequently substituted as the gate electrode with PEDOT:PSS serving as an organic semiconductor material. The resulting OECT sensor provided a favourable microenvironment for protein activity, maintaining high specificity. Exclusive phenol detection with minimal loss of sensitivity (<5% error) could be achieved in both complex pollutant mixtures and real environmental samples. This fabrication strategy that amalgamates biological biosensors with organic electronics harnesses the potential to achieve detection of a host of emerging pollutants.

Inkjet-printed sub-zero temperature sensor for real-time monitoring of cold environments.

Real-time monitoring of low temperatures (usually below 0 °C) or cold environments is a specific requirement that finds its high demand in the aerospace, pharmaceutical, food, and beverage industries to maintain the temperature at high altitudes or in refrigerators and cold storage. In general, this purpose is achieved by using a sub-zero temperature sensor coupled with a control system. However, the market available such temperature sensors are very expensive, and bulky, thus not being suitable for portable operation, and also they suffer from poor accuracy. Therefore, the development of high-performance, low-cost, lightweight, and portable sub-zero temperature sensors is highly desired. In our recent work, we developed such sensors and integrated them with auxiliary electronics to demonstrate their wireless operation for the continuous and real-time monitoring of cold environments. So, in order to obtain low-cost sensors a cost-effective inkjet printing technology was employed for the fabrication of devices. A lightweight polydimethylsiloxane (PDMS) was used as the substrate and an electrically conducting graphene nanocomposite was used as the temperature-sensing material. To obtain a functional graphene nanocomposite film with a thickness of 530 nm and a conductivity of ~189 S m-1, the printed graphene nanocomposite was photonically sintered using a xenon flash lamp. This step was crucial for obtaining a sensor on the soft PDMS platform. The graphene nanocomposite film exhibited a positive temperature coefficient resistance value of approximately 0.119 %/°C, and its resistance values varied almost linearly (with an Adjusted R2 value (model accuracy) of 0.99) with temperature within the operating range of -30 °C to 80 °C. The sensor was properly encapsulated for protection without significantly affecting its performance. The sensors demonstrated sufficient flexibility, with a bending radius of 20 mm, and sustained 500 continuous bending cycles. Finally, the real-time operation of the sensors was demonstrated by wirelessly transmitting and monitoring the temperature over a smartphone platform.

Lesion Localization Using Digital Breast Tomosynthesis: Where Did I Go Wrong?

The scroll bar on digital breast tomosynthesis has become an imperative tool that breast imaging radiologists rely on for help in identify lesions on the orthogonal view, targeting breast ultrasound, and performing challenging biopsies for one-view findings. The ability to predict the lesion location using the scroll bar not only saves time in the diagnostic setting but also reduces screening recalls when a finding can be confirmed as dermal. It is important, however, to recognize settings in which the location prediction can be misleading, such as for lesions in thin breast tissue or the anterior portion of the breast or if the breast is not appropriately positioned. In these situations, radiologists can use other diagnostic tools for problem solving.

Digital Breast Tomosynthesis: Clinical Operations.

Digital breast tomosynthesis (DBT) is rapidly becoming the standard of care for breast cancer screening. Implementing DBT into practice is relatively straightforward. However, there are important elements of the transition that one must consider to facilitate this process. Understanding the Digital Imaging and Communications in Medicine (DICOM) standard for DBT, as well as how images are displayed, is critical to a successful transition. Standardization of these processes will allow easier transmission of images from facility to facility, and limit the potential for errors in interpretation. Additionally, recent changes in federal regulations will require compliance with mandated training for the radiologist, technologist, and physicist, as well as accreditation for each DBT unit. These regulations aim to ensure high-quality imaging across the country as has been previously seen with standard digital mammography. Synthesized imaging is the most recent improvement for DBT, potentially obviating the need for a simultaneous traditional digital mammogram exposure. Studies have demonstrated near equivalent performance when comparing the combination imaging of DBT and digital mammography versus DBT combined with synthetic imaging. As the quality of the synthetic images continues to improve, it is increasingly likely that it will replace the traditional mammogram. Adherence to DBT-specific parameters will enhance the physician experience and ultimately translate to increased cancer detection and fewer false positive examinations, benefiting all women who are screened for breast cancer.