Informational Deoxyribonucleic Acid (iDNA) has gained the attention of many researchers and pioneer companies for the development of novel storage systems for the long-term and high-density storing of information. This research focuses on the physical storage of iDNA strands to address some of the current challenges by evaluating the accuracy of the process of iDNA retrieval from the surface after the dehydration process. For this aim, a UV-Vis spectrophotometric technique was used to measure the concentration of the DNA samples. Although spectroscopy has been widely employed for the evaluation of DNA concentration and contamination in a solution, it has not been used to investigate dry-state DNA, which is one of the preferred storage formats for the long-term retention of information. These results demonstrate that the UV-Vis spectrophotometric technique can be used to accurately measure dry-state DNA before the retrieval and its residues after the DNA retrieval process. This paper further examines the storage/retrieval process by investigating the relationship between the storage time and the amount of retrieved DNA or the DNA residue left on various surfaces. Based on the experimental results demonstrated and discussed in this paper, UV-Vis spectrophotometry can be used for monitoring dry-state DNA with a high accuracy larger than 98%. Moreover, these results reveal that the hydrophilicity and hydrophobicity of the surface do not significantly affect DNA retrieval over a one-month time period.

Polycyclic aromatic hydrocarbons (PAHs) are increasingly recognized as a major contributor to the occupational cancer risk among firefighters. In response, the National Fire Protection Association (NFPA) and other regulatory bodies have recommended rigorous decontamination protocols to minimize PAH exposure. Despite these efforts, a critical gap persists: the absence of real-time, field-deployable devices capable of detecting these invisible and toxic compounds during firefighting operations or within fire stations. Additionally, the lack of effective and optimized methods for the removal of these hazardous substances from the immediate environments of firefighters continues to pose a serious occupational health challenge. Although numerous studies have investigated PAH detection in environmental contexts, current technologies are still largely confined to laboratory settings and are unsuitable for field use. This review critically examines recent advances in PAH decontamination strategies for firefighting and explores alternative sensing solutions. We evaluate both conventional analytical methods, such as gas chromatography, high-performance liquid chromatography, and mass spectrometry, and emerging portable PAH detection technologies. By highlighting the limitations of existing systems and presenting novel sensing approaches, this paper aims to catalyze innovation in sensor development. Our ultimate goal is to inspire the creation of robust, field-deployable tools that enhance decontamination practices and significantly improve the health and safety of firefighters by reducing their long-term risks of cancer.

This article presents a novel open gate junction field-effect transistor (OG-JFET)-based sensor that can be used for various life science applications including deoxyribonucleic acid (DNA) storage monitoring. We put forward the design, modeling, implementation, and characterization of OG-JFET sensor using a foundry process through CMC Microsystems. We also demonstrate and discuss the functionality and applicability of the proposed sensor for monitoring DNA samples suitable for DNA storage applications. Synthetic storage has emerged as an intriguing data storage solution with high density and long-term preservation potential. Most common modalities include the conversion of digital data into synthesized nucleotides, the physical storage of DNA materials, and reading out the data via sequencing and other computational processes. Among these, this article tackles the challenge of physical storage monitoring of DNA materials by developing a sensor for measurement of DNA samples in dry conditions. The proposed sensor reveals a linear response of sensor toward DNA concentration in ultra-pure water. Across a 0.7 mm ² sensing area, a DNA mass concentration from approximately 100–400 ng/ $\mu \text{L}$ has been detected using OG-JFET demonstrating a sensitivity of 30 $\mu \text{A}$ /(ng/ $\mu \text{L}$ ). These performance quantities imply a promising role for OG-JFETs in emerging biotechnology applications including DNA storage monitoring.

In this paper, we present, for the first time, the advantage of CMOS capacitive sensor for the assessment of dried DNA from an aqueous sample for DNA storage applications. The proposed capacitive sensor consists of a differential capacitance to current converter block based on a core-CBCM circuit, a 300 MHz current controlled oscillator and a 12-bit counter that creates the digital output of the chip. The chip has been fabricated using AMS 0.35µm technology. We demonstrate the functionality and applicability of the proposed sensor for dried DNA nano-mass measurement using single-strand DNA samples. The sensor shows acceptable repeatability in quantifying the DNA nano-mass with a sensitivity of 18.5 aF/ng mass of DNA based on the results described here.

This paper presents the design, and implementation of a new CMOS capacitive sensor and proposes the applicability of the sensor in monitoring the dried DNA mass for the emerging DNA memory technologies. The concept of DNA-based data storage has shown to be a promising solution with an ultra-high data density storage capability of gigabytes per nanogram mass of DNA. There are several drawbacks in achieving a ubiquitous technology and existing research has mostly addressed the translation of digital data to synthesized nucleotides, the physical storage of DNA, and reading out the data via sequencing, as well as computational processes. In this paper, we tackle the challenge of monitoring the physical storage of dried DNA material by developing a CMOS capacitive sensor that detects the dried DNA mass and inherits the highly integrable nature of CMOS chips with other parts to develop a DNA storage system. The successful detection of down to 45 ng $/ \boldsymbol {\mu }\text{L}$ mass of dried DNA has been successfully shown with the experimental results that consist of five runs for five different concentrations. Based on the results, the detection range of sub-pico Mol has been achieved which is compatible with the concentrations of DNA used in DNA memory technologies.

This article introduces a new field-effect transistor (FET)-based sensing system designed to monitor charge/polarity changes during the evaporation of microsize water droplets containing polar substances such as ethanol and methanol. The system utilizes a high transconductance interdigital open-gate junction FET (ID-OGJFET) with a sizeable direct-on-channel sensing area (>16 mm2) in direct contact with the liquid droplet. A new electrofluidic package has also been developed to facilitate sample access on the FET chip, which prevents leakage and connects the sensor to readout systems. An experimental procedure is designed to demonstrate the functionality and applicability of this FET platform sensing system for chemical analysis, such as measuring the concentration of ethanol or methanol in water using the evaporation-based sensing mechanism enabled by the ID-OGJFET. Real-time video capture is employed for monitoring and control. The sensor measures ethanol and methanol concentrations ranging from 0% to 100% with steps of 10% EtOH/MetOH in water, utilizing the evaporation-based sensing mechanism and current output of the ID-OGJFET sensor. The minimum meaningful measured concentration is 1% (v/v) for ethanol and 1.49% (v/v) for methanol. The combined uncertainty analysis of methanol’s concentration predictions ranged from 3.29 to 77.91 s. The expanded uncertainty varied from 6.58 to 155.82 s at a 95% confidence level for concentrations from 0% v/v to 100% with 10% intervals. For ethanol, the combined uncertainties ranged from 4.68 to 98.95 s. The expanded uncertainties, calculated with a coverage factor 2, varied from 9.36 to 197.90 s at a 95% confidence level.