Portable light detectors for bioluminescence biosensing applications: A comprehensive review from the analytical chemist's perspective

Bioluminescence, that is the emission of light in living organisms, has been extensively explored and applied for diverse bioanalytical applications, spanning from molecular imaging to biosensing. The unprecedented technological evolution of portable light detectors opened new possibilities to implement bioluminescence detection into miniaturized devices. We are witnessing a number of applications, including DNA sequencing, reporter gene assays, DNA amplification for point-of care and point-of need analyses relying on BL. Several photon detectors are currently available for measuring low light emission, such as photomultiplier tubes (PMT), charge-coupled devices (CCD), complementary metal oxide semiconductors (CMOS), single photon avalanche diodes (SPADs), silicon photomultipliers (SiPMs) and smartphone-integrated CMOS. Each technology has pros and cons and several issues, such as temperature dependence of the instrumental specific noise, the power supply, imaging capability and ease of integration, should be considered in the selection of the most appropriate detector for the selected BL application

Smartphone-based food diagnostic technologies: A review

A new generation of mobile sensing approaches offers significant advantages over traditional platforms in terms of test speed, control, low cost, ease-of-operation, and data management, and requires minimal equipment and user involvement. The marriage of novel sensing technologies with cellphones enables the development of powerful lab-on-smartphone platforms for many important applications including medical diagnosis, environmental monitoring, and food safety analysis. This paper reviews the recent advancements and developments in the field of smartphone-based food diagnostic technologies, with an emphasis on custom modules to enhance smartphone sensing capabilities. These devices typically comprise multiple components such as detectors, sample processors, disposable chips, batteries and software, which are integrated with a commercial smartphone. One of the most important aspects of developing these systems is the integration of these components onto a compact and lightweight platform that requires minimal power. To date, researchers have demonstrated several promising approaches employing various sensing techniques and device configurations. We aim to provide a systematic classification according to the detection strategy, providing a critical discussion of strengths and weaknesses. We have also extended the analysis to the food scanning devices that are increasingly populating the Internet of Things (IoT) market, demonstrating how this field is indeed promising, as the research outputs are quickly capitalized on new start-up companies

Smartphone as a Portable Detector, Analytical Device, or Instrument Interface

The Encyclopedia Britannia defines a smartphone as a mobile telephone with a display screen, at the same time serves as a pocket watch, calendar, addresses book and calculator and uses its own operating system (OS). A smartphone is considered as a mobile telephone integrated to a handheld computer. As the market matured, solid-state computer memory and integrated circuits became less expensive over the following decade, smartphone became more computer-like, and more more-advanced services, and became ubiquitous with the introduction of mobile phone networks. The communication takes place for sending and receiving photographs, music, video clips, e-mails and more. The growing capabilities of handheld devices and transmission protocols have enabled a growing number of applications. The integration of camera, access Wi-Fi, payments, augmented reality or the global position system (GPS) are features that have been used for science because the users of smartphone have risen all over the world. This chapter deals with the importance of one of the most common communication channels, the smartphone and how it impregnates in the science. The technological characteristics of this device make it a useful tool in social sciences, medicine, chemistry, detections of contaminants, pesticides, drugs or others, like so detection of signals or image

Exploiting bioluminescence to enhance the analytical performance of whole-cell and cell-free biosensors for environmental and point-of-care applications

The routine health monitoring of living organisms and environment has become one of the major concerns of public interest. Therefore, there has been an increasing demand for fast and easy to perform monitoring technologies. The current available analytical techniques generally offer accurate and precise results; however, they often require clean samples and sophisticated equipment. Thus, they are not suitable for on site, real-time, cost-effective routine monitoring. To this end, biosensors represent suitable analytical alternative tools. Biosensors are analytical devices integrating a biological recognition element (i.e. antibody, receptor, cell) and a transducer able to convert the biological response into an easily measurable analytical signal. These tools can easily quantify an analyte or a class of analytes of interest even in a complex matrix, like clinical or environmental samples, thanks to the specificity of the biological components. Whole-cell biosensors among others offer unique features such as low cost of production and provide comprehensive functional information (i.e. detection of unclassified compounds and synergistic effects, information about the bioavailable concentration). During this PhD, several bioengineered whole-cell biosensors have been developed and optimized for environmental and point-of-care applications. Analytical performance of biosensors have been improved (i.e. low limit of detection, faster response time and wider dynamic range) thanks to synthetic biology and genetic engineering tools. Bacterial, yeast and 3D cell cultures of mammalian cell lines have been tailored at the molecular level to improve robustness and predictivity. Several reporter genes, i.e. colorimetric, fluorescent and bioluminescent proteins, have been also profiled for finding the best candidate for each point-of-need application. Furthermore, spectral resolution of different optical reporter proteins has been exploited and multiplex detection has been achieved. The inclusion of viability control strains provided a suitable tool for assessing non-specific effects on cell viability, correcting the analytical signal and increasing the analytical performance of ready-to-use cartridges

Smartphone-based colorimetric sensor application for measuring biochemical material concentration

In this paper, colorimetric analysis for biochemical samples has been realized, by developing an easy-to-use smartphone colorimetric sensing android application that can measure the molar concentration of the biochemical liquid analyte. The designed application can be used for on-site testing and measurement. We examined three different biochemical materials with the application after preparation with five different concentrations and testing in laboratory settings, namely glucose, triglycerides, and urea. Our results showed that for glucose triglycerides, and urea the absorbance and transmittance regression coefficient (R2) for the colorimetric sensing application were 0.9825, and 0.9899; 0.9405 and 0.9502; 0.9431 and 0.8597, respectively. While for the spectrophotometer measurement the (R2) values were 0.9973 @560 nm and 0.9793 @600 nm; 0.952 @620 nm and 0.9364 @410 nm; 0.9948 @570 nm and 0.9827 @530 nm, respectively. The novelty of our study lies in the accurate prediction of multiple biochemical materials concentrations in various lightning effects, reducing the measurement time in an easy-to-use portable environment without the need for internet access, also tackling various issues that arise in the traditional measurements like power consumption, heating, and calibration. The ability to convey multiple tasks, prediction of concentration, measurement of both absorbance and transmittance, with error estimation charts and (R2) values reporting within the colorimetric sensing application as far as our knowledge there has not been any application that can provide all the capabilities of our application

Smartphone-based optical assays in the food safety field.

Smartphone based devices (SBDs) have the potential to revolutionize food safety control by empowering citizens to perform screening tests. To achieve this, it is of paramount importance to understand current research efforts and identify key technology gaps. Therefore, a systematic review of optical SBDs in the food safety sector was performed. An overview of reviewed SBDs is given focusing on performance characteristics as well as image analysis procedures. The state-of-the-art on commercially available SBDs is also provided. This analysis revealed several important technology gaps, the most prominent of which are: (i) the need to reach a consensus regarding optimal image analysis, (ii) the need to assess the effect of measurement variation caused by using different smartphones and (iii) the need to standardize validation procedures to obtain robust data. Addressing these issues will drive the development of SBDs and potentially unlock their massive potential for citizen-based food control

Microfluidic paper-based analytical devices with instrument-free detection and miniaturized portable detectors

icrofluidic paper-based analytical devices (mu PADs) have attracted much attention over the past decade because they offer clinicians the ability to deliver point-of-care testing and onsite analysis. Many of the advantages of mu PADs, however, are limited to work in a laboratory setting due to the difficulties of processing data when using electronic devices in the field. This review focuses on the use of mu PADs that have the potential to work without batteries or with only small and portable devices such as smartphones, timers, or miniaturized detectors. The mu PADs that can be operated without batteries are, in general, those that allow the visual judgment of analyte concentrations via readouts that are measured in time, distance, count, or text. Conversely, a smartphone works as a camera to permit the capture and processing of an image that digitizes the color intensity produced by the reaction of an analyte with a colorimetric reagent. Miniaturized detectors for electrochemical, fluorometric, chemiluminescence, and electrochemiluminescence methods are also discussed, although some of them require the use of a laptop computer for operation and data processing

Recent Advancements in the Technologies Detecting Food Spoiling Agents

To match the current life-style, there is a huge demand and market for the processed food whose manufacturing requires multiple steps. The mounting demand increases the pressure on the producers and the regulatory bodies to provide sensitive, facile, and cost-effective methods to safeguard consumers’ health. In the multistep process of food processing, there are several chances that the food-spoiling microbes or contaminants could enter the supply chain. In this contest, there is a dire necessity to comprehend, implement, and monitor the levels of contaminants by utilizing various available methods, such as single-cell droplet microfluidic system, DNA biosensor, nanobiosensor, smartphone-based biosensor, aptasensor, and DNA microarray-based methods. The current review focuses on the advancements in these methods for the detection of food-borne contaminants and pathogens

Micro-Biosensor Devices for Biochemical Analysis Applications

A biosensor is an analytical device integrating a biological element and a physicochemical transducer that convert a biological response into a measurable signal. The advantages of biosensors include low cost, small size, quick, sensitivity and selectivity greater than the conventional instruments. Biosensors have a wide range of applications ranging from clinical diagnostics through to environmental monitoring, agriculture industry, et al. The different types of biosensors are classified based on the sensor device as well as the biological material. Biosensors can be broadly classified into (piezoelectric, etc.), electrochemical biosensors (potentiometric, amperometric, etc.), and optical types of biosensors (fiber optics, etc.). Here, we introduce a novel microfluidics-integrated biosensor platform system that can be flexibly adapted to form individual biosensors for different applications. In this dissertation, we present five examples of different emerging areas with this biosensor system including anti-cancer drug screening, glucose monitoring, heavy metal elements measurement, obesity healthcare, and waterborne pathogen DNA detection. These micro-biosensors have great potential to be further developed to emerging portable sensing devices especially for the uses in the developing and undeveloped world. At the last chapter, Raman spectroscopy applied to assess gestational status and the potential for pregnancy complications is presented and discussed. This technique could significantly benefit animal reproduction

Application of Paper-Based Microfluidic Analytical Devices (µPAD) in Forensic and Clinical Toxicology: A Review

The need for providing rapid and, possibly, on-the-spot analytical results in the case of intoxication has prompted researchers to develop rapid, sensitive, and cost-effective methods and analytical devices suitable for use in nonspecialized laboratories and at the point of need (PON). In recent years, the technology of paper-based microfluidic analytical devices (μPADs) has undergone rapid development and now provides a feasible, low-cost alternative to traditional rapid tests for detecting harmful compounds. In fact, μPADs have been developed to detect toxic molecules (arsenic, cyanide, ethanol, and nitrite), drugs, and drugs of abuse (benzodiazepines, cathinones, cocaine, fentanyl, ketamine, MDMA, morphine, synthetic cannabinoids, tetrahydrocannabinol, and xylazine), and also psychoactive substances used for drug-facilitated crimes (flunitrazepam, gamma- hydroxybutyric acid (GHB), ketamine, metamizole, midazolam, and scopolamine). The present report critically evaluates the recent developments in paper-based devices, particularly in detection methods, and how these new analytical tools have been tested in forensic and clinical toxicology, also including future perspectives on their application, such as multisensing paper-based devices, microfluidic paper-based separation, and wearable paper-based sensors