Miniaturized Devices for Isothermal Amplification and Photometric Quantification of Pseudomonas Aeruginosa.

This study introduced a proof-of-concept prototype for isothermal recombinase polymerase amplification (RPA) with miniaturized photometric detection, enabling rapid P. aeruginosa detection. The researchers conducted the amplification process within a microchamber with a diameter of 10 mm, utilizing a standalone Thermostat driven thermal management setup.

Surface plasmon enhanced auto-fluorescence and Raman spectroscopy for low-level detection of biological pathogens.

The current culture-based bacterial detection technique is time-consuming and requires an extended sample preparation methodology. We propose the potential of surface-enhanced Raman spectroscopy (SERS) and surface plasmon-enhanced auto-fluorescence spectroscopy (SPEAS) for the label-free identification and quantification of bacterial pathogens at low concentrations collecting its unique auto-fluorescence and Raman signatures utilising highly anisotropic three-dimensional nanostructures of silver nano dendrites (Ag-NDs). The SERS data facilitates qualitative bacterial identification using the spectral features coming from the bacterial cell wall compound, and the SPEAS data was utilised to gain unique auto-fluorescence spectra present on the bacterial cell wall with enhanced quantification.

Quantification of urinary albumin in clinical samples using smartphone enabled LFA reader incorporating automated segmentation.

Smartphone-assisted urine analyzers estimate the urinary albumin by quantifying color changes at sensor pad of test strips. These strips yield color variations due to the total protein present in the sample, making it difficult to relate to color changes due to specific analyte. We have addressed it using a Lateral Flow Assay (LFA) device for automatic detection and quantification of urinary albumin.

PlQC based highly sensitive and reproducible novel SERS active substrate for biomolecule detection with high specificity.

Surface-enhanced Raman spectroscopy (SERS) is a powerful tool for biomolecule sensing. When combined with a broadband plasmonic structure, label-free, highly sensitive detection of specific molecules is possible. It is non-invasive, sensitive, fast, and can be used for in-situ analysis, unlike enzyme-linked immunosorbent assay, fluorescence immunoassay, and radioimmunoassay.

A review: early detection of oral cancer biomarkers using microfluidic colorimetric point-of-care devices.

Oral squamous cell carcinoma (OSCC) is the most common type of head and neck cancers. OSCC constitutes 90% of the head and neck malignancies. The delayed identification of oral cancer is the primary cause of ineffective medical treatment.

Machine learning assisted and smartphone integrated homogeneous electrochemiluminescence biosensor platform for sample to answer detection of various human metabolites.

The sensitive and accurate detection of glucose and lactate is essential for early diagnosis and effective management of diabetes complications. Herein, a 3D Printed ECL imaging system integrated with a Smartphone has been demonstrated to advance the traditional ECL to make a portable, affordable, and turnkey point-of-care solution to detect various human metabolites. A universal cross-platform application was introduced for analyzing ECL emitted signals to automate the whole detection process for real-time monitoring and rapid diagnostics.

A protocol to execute a lab-on-chip platform for simultaneous culture and electrochemical detection of bacteria.

Here, we present a protocol for a miniaturized microfluidic device that enables quantitative tracking of bacterial growth. We describe steps for fabricating a screen-printed electrode, a laser-induced graphene heater, and a microfluidic device with its integrations. We then detail the electrochemical detection of bacteria using a microfluidic fuel cell.

Microfluidic Device Integrated With PDMS Microchannel and Unmodified ITO Glass Electrodes for Highly Sensitive, Specific, and Point-of-Care Detection of Copper and Mercury.

This work delves upon developing a two-layer plasma-bonded microfluidic device with a microchannel layer and electrodes for electroanalytical detection of heavy metal ions. The three-electrode system was realized on an ITO-glass slide by suitably etching the ITO layer with the help of CO2 laser. The microchannel layer was fabricated using a PDMS soft-lithography method wherein the mold created by maskless lithography.

Nanogap-Rich Surface-Enhanced Raman Spectroscopy-Active Substrate Based on Double-Step Deposition and Annealing of the Au Film over the Back Side of Polished Si.

Surface-enhanced Raman spectroscopy (SERS) is a highly sensitive and rapid detection technique that is used for detection of various analytes in trace quantities. We present a sensitive, large-area, and nanogap-rich SERS-active substrate by altering a thin gold (Au) film on the unpolished side of a single-side polished silicon wafer by repeated thermal deposition and annealing in an argon environment. The repeated thermal deposition and annealing process was compared on both sides of a one-side-polished silicon wafer; however, the rear side (etched/unpolished side) demonstrated a more enhanced Raman signal owing to the larger effective area.

Optimized porous carbon-fibre microelectrode for multiplexed, highly reproducible and repeatable detection of heavy metals in real water samples.

This work demonstrates the simultaneous identification of four hazardous heavy metals in water samples, namely copper, lead, cadmium, and mercury. A simple yet selective electrode with the simplest fabrication procedure was used. The modified porous carbon threads coated with gold nanoparticles (AuNPs) was employed as a working electrode.

A lab-on-chip platform for simultaneous culture and electrochemical detection of bacteria.

A simple, cost-effective and miniaturized lab-on-a-chip platform has been developed amenable to perform simultaneous cultivation and detection of bacteria. A microfluidic chamber was integrated to screen-printed electrodes for electrochemical detection of bacteria. The temperature required for the bacterial culture was provided through the optimized laser-induced graphene heaters.

Disposable Miniaturized Electrochemical Sensing Platform With Laser-Induced Reduced Graphene Oxide Electrodes for Multiplexed Biochemical Analysis.

Metabolic biomarkers, such as Dopamine (DA), Uric acid (UA), and Ascorbic acid (AA), have significant roles in determining the physiological functioning of the human body. These are often analyzed through clinical lab-based procedures which are bulky and require skilled technicians. In view of this, the design, development, and fabrication of a portable, cost-effective, user-friendly, and disposable device for electro-analytical detection, leading to point-of-care (POC) detection of these metabolic biomarkers is a pressing need.

Three Different Rapidly Prototyped Polymeric Substrates With Interdigitated Electrodes for Escherichia coli Sensing: A Comparative Study.

This work delves upon the development of different types of miniaturized and 3D printed devices having interdigitated electrodes (IDEs) for the detection of Escherichia coli (E. coli) bacteria. The IDEs were fabricated using different approaches including laser-induced graphene (LIG) on polyamide, direct laser writing on glass, and polymeric 3D printing technique, and their suitability for bacteria detection has been compared.

Modified Ultra Micro-Carbon Electrode for Efficient Ammonia Sensing for Water Quality Assessment.

Ammonia is one of the most prominent and hazardous water pollutants; hence its selective and sensitive detection in water is crucial for monitoring water quality and determining its usability. In the present work, a simple, cost-effective electrochemical sensor for the detection of ammonia is presented. Multi-walled carbon nanotubes modified ultra-micro-carbon thread electrode (UME/MWCNT) has been realized.

Miniaturized 3D printed electrochemical platform with optimized Fibrous carbon electrode for non-interfering hypochlorite sensing.

3D printing technology based electrochemical device can provide ease of fabrication, cost effectiveness, rapid detection and lower limit of detection. Herein, a novel, customized, portable and inexpensive 3D printed electrochemical device, has been presented. Fibrous carbon Toray paper, deposited with gold nanoparticles through electrodeposition, used as a working electrode which Further device was tested with 1 mM sodium hypochlorite using cyclic voltammetry (CV) and square wave voltammetry (SWV) in 0.

Rapid Inkjet-Printed Miniaturized Interdigitated Electrodes for Electrochemical Sensing of Nitrite and Taste Stimuli.

This paper reports on single step and rapid fabrication of interdigitated electrodes (IDEs) using an inkjet printing-based approach. A commercial inkjet-printed circuit board (PCB) printer was used to fabricate the IDEs on a glass substrate. The inkjet printer was optimized for printing IDEs on a glass substrate using a carbon ink with a specified viscosity.

Experimental studies on droplet characteristics in a microfluidic flow focusing droplet generator: effect of continuous phase on droplet encapsulation.

The efficacy of droplet-based microfluidic assays depends on droplet size, pattern, generation rate, etc. The size of the droplet is affected by numerous variables as flow rate ratio, viscosity ratio, microchannel geometry, surfactants, nature of fluids and other dimensionless numbers. This work reports rigorous analysis and optimization of the behavior of droplets with change in flow rate ratio and viscosity ratio in a flow-focusing device.

Optimized ink jetted paper device for electroanalytical detection of picric acid.

Picric acid (PA) is one of the essential components utilized in manufacturing of explosives. Therefore, the detection of trace amount of PA is critical in forensic science, criminal investigation, military security and environmental safety. Owing to these attributes, development of a simple, rapid and point-of-care (POC) analytical method for PA detection and quantification is crucial.

Electrochemical Mini-Platform With Thread- Based Electrodes for Interference Free Arsenic Detection.

Herein, a fully integrated thread/textile-based electrochemical sensing device has been demonstrated. A hydrophilic conductive carbon thread, chemically modified with gold nanoparticles through an electrodeposition process, was used as a working electrode (WE). The hydrophilic thread coated with Ag/AgCl and an unmodified bare hydrophilic thread were used as reference electrode (RE) and counter electrode (CE) respectively.

Droplet-based lab-on-chip platform integrated with laser ablated graphene heaters to synthesize gold nanoparticles for electrochemical sensing and fuel cell applications.

Controlled, stable and uniform temperature environment with quick response are crucial needs for many lab-on-chip (LOC) applications requiring thermal management. Laser Induced Graphene (LIG) heater is one such mechanism capable of maintaining a wide range of steady state temperature. LIG heaters are thin, flexible, and inexpensive and can be fabricated easily in different geometric configurations.

Highly Sensitive and Interference-Free Electrochemical Nitrite Detection in a 3D Printed Miniaturized Device.

3D printing has a significant impact on various applications as it facilitates greater control over the designed shapes, leads to rapid prototyping and mass production with transferable designs at a lower cost. These attributes provide great versatility and thus make the devices industry-friendly. Herein, we demonstrate a simple and disposable 3D printed device, fabricated in single-step, as an electrochemical nitrite sensor using commercially available carbon loaded polylactic acid (PLA) filament.

Automated pencil electrode formation platform to realize uniform and reproducible graphite electrodes on paper for microfluidic fuel cells.

Graphite pencil stroked electrodes for paper-based Microfluidic devices are gaining immense attention due to their electrochemical properties, cost efficiency, and ease-of-use. However, their widespread use has been hindered by the challenges associated with their manual fabrication such as non-uniformity in graphite deposition, applied pressure, etc. This work presents the design and development of an automated graphite pencil stroking device for graphite electrode fabrication with high efficiency through a compact, inexpensive and automatic process, with reduced fabrication time and human intervention leading to more uniformity.

Design and development of volume phase holographic grating based digital holographic interferometer for label-free quantitative cell imaging.

In this paper, a volume phase holographic optical element based digital holographic interferometer is designed and used for quantitative phase imaging of biological cells [white blood cells, red blood cells, platelets, and Staphylococcus aureus (S. aureus) bacteria cells]. The experimental results reveal that sharp images of the S.

Fully Integrated, Automated, and Smartphone Enabled Point-of-Source Portable Platform With Microfluidic Device for Nitrite Detection.

Excess limit of Nitrites, which are prevalent within environmental and physiological systems, have severe detrimental effects, thus point-of-source detection becomes an important requirement to take suitable preventive measures. This paper presents the design and development of a standalone, point-of-source, portable, low-cost, automated and integrated microfluidic system for quick detection and quantification of nitrite. Based on multiphysics simulations, a disposable polydimethylsiloxane (PDMS) microfluidic device was employed to carry out the controlled Griess reaction based assay.

Two-wavelength Talbot effect and its application for three-dimensional step-height measurement.

The phenomenon of Talbot self-image shift by changing the wavelength of the illuminating light is described and demonstrated experimentally. A periodic grating is illuminated by light with wavelengths lambda1 and lambda2 generated by two lasers, and the Talbot self-images are recorded along the longitudinal direction at individual wavelengths. The Talbot self-image shift due to the change in the wavelength of light is implemented for the measurement of the three-dimensional step height of a large discontinuous object without any phase ambiguity problem.