Evaluating Low-Cost Optical Spectrometers for the Detection of Simulated Substandard and Falsified Medicines

Distribution of substandard and falsified (SF) medicines is on the rise, and its impact on public health, particularly in low-resource countries, is becoming increasingly significant. Portable, nondestructive screening devices can support regulatory authorities in their defense against the spread of SF medicines. Vibrational spectroscopy is an ideal candidate due to its sampling ease and speed. In this work, five portable, among which four are considered low-cost, spectroscopic devices based on near-infrared (NIR), Raman, and mid-infrared (MIR) were evaluated to quantify active pharmaceutical ingredients (APIs) and formulation accuracy within simulated authentic, falsified, and substandard medicines. Binary sample mixtures containing a typical API in antimalarial, antiretroviral, or anti-tuberculosis medicines were assessed. In both univariate and multivariate analyses, the API quantification performance of the digital light processing (DLP) NIR spectrometer and a handheld Raman device consistently matched or exceeded that of the other NIR spectrometers and a scientific grade MIR spectrometer. In the formulation accuracy tests, data from all devices, other than the silicon photodiode array NIR spectrometer, were able to create regression models with less than 6% error. From this exploratory study, we conclude that certain portable NIR devices hold significant promise as cost-effective screening tools for falsified and potentially substandard medicines, and they warrant further investigation and development.

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Portable, Low-Cost, Solid-State Luminescence-Based O2 Sensor

Applied Spectroscopy ◽

10.1366/0003702981944175 ◽

1998 ◽

Vol 52 (5) ◽

pp. 750-754 ◽

Cited By ~ 51

Author(s):

A. Neal Watkins ◽

Brett R. Wenner ◽

Jeffrey D. Jordan ◽

Wenying Xu ◽

James N. Demas ◽

...

Keyword(s):

Solid State ◽

Response Times ◽

Ruthenium Complex ◽

Light Emitting Diode ◽

Low Cost ◽

Sol Gel ◽

Cost Effective ◽

Fast Response ◽

Color Filter ◽

Silicon Photodiode

A novel sensor for quantifying molecular O2 based entirely on solid-state electronics is presented. The sensor is based on the luminescence quenching of tris(4,7-diphenyl-1, 10-phenanthroline)ruthenium(II) ([Ru(dpp)3]2+) by molecular O2. The sensor involves immobilizing the ruthenium complex within a porous sol-gel-processed glass film and casting this film directly onto the surface of a blue quantum-well light-emitting diode (LED). The ruthenium complex is excited by the LED, the [Ru(dpp)3]2+ emission is filtered from the excitation with a low-cost acrylic color filter, and the emission is detected with an inexpensive silicon photodiode. The sensor response to gaseous O2 and dissolved O2 in water is presented. The sensor exhibits fast response times and good reversibility, and detection limits are 0.5%, 0.02%, and 110 ppb, respectively, for O2 in the gaseous (linear Stern–Vobner and multi-site Stern–Volmer analysis) and aqueous phase. This sensor provides a cost-effective alternative to traditional electrochemical-based O2 sensing and also provides a platform for other optically based sensors.

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A Cost-Effective and Portable Optical Sensor System to Estimate Leaf Nitrogen and Water Contents in Crops

Sensors ◽

10.3390/s20051449 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1449 ◽

Cited By ~ 1

Author(s):

Mohammad Habibullah ◽

Mohammad Reza Mohebian ◽

Raju Soolanayakanahally ◽

Khan A. Wahid ◽

Anh Dinh

Keyword(s):

Water Content ◽

Near Infrared ◽

Low Cost ◽

Gaussian Process Regression ◽

Cost Effective ◽

Leaf Nitrogen ◽

Sensor System ◽

Coefficient Of Determination ◽

Healthy Growth ◽

Water Contents

Non-invasive determination of leaf nitrogen (N) and water contents is essential for ensuring the healthy growth of the plants. However, most of the existing methods to measure them are expensive. In this paper, a low-cost, portable multispectral sensor system is proposed to determine N and water contents in the leaves, non-invasively. Four different species of plants—canola, corn, soybean, and wheat—are used as test plants to investigate the utility of the proposed device. The sensor system comprises two multispectral sensors, visible (VIS) and near-infrared (NIR), detecting reflectance at 12 wavelengths (six from each sensor). Two separate experiments were performed in a controlled greenhouse environment, including N and water experiments. Spectral data were collected from 307 leaves (121 for N and 186 for water experiment), and the rational quadratic Gaussian process regression (GPR) algorithm was applied to correlate the reflectance data with actual N and water content. By performing five-fold cross-validation, the N estimation showed a coefficient of determination ( R 2 ) of 63.91% for canola, 80.05% for corn, 82.29% for soybean, and 63.21% for wheat. For water content estimation, canola showed an R 2 of 18.02%, corn showed an R 2 of 68.41%, soybean showed an R 2 of 46.38%, and wheat showed an R 2 of 64.58%. The result reveals that the proposed low-cost sensor with an appropriate regression model can be used to determine N content. However, further investigation is needed to improve the water estimation results using the proposed device.

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Vein Pattern Locating Technology for Cannulation: A Review of the Low-Cost Vein Finder Prototypes Utilizing near Infrared (NIR) Light to Improve Peripheral Subcutaneous Vein Selection for Phlebotomy

Sensors ◽

10.3390/s19163573 ◽

2019 ◽

Vol 19 (16) ◽

pp. 3573 ◽

Cited By ~ 5

Author(s):

Cheng-Tang Pan ◽

Mark D. Francisco ◽

Chung-Kun Yen ◽

Shao-Yu Wang ◽

Yow-Ling Shiue

Keyword(s):

Near Infrared ◽

Infrared Imaging ◽

Low Cost ◽

Venous Blood ◽

Cost Effective ◽

Medical Laboratory ◽

Scientific Publications ◽

Medical Practitioners ◽

Nir Light ◽

Number Of Patients

One of the most common means for diagnosis is through medical laboratory testing, which primarily uses venous blood as a sample. This requires an invasive method by cannulation that needs proper vein selection. The use of a vein finder would help the phlebotomist to easily locate the vein, preventing possible pre-analytical error in the specimen collection and even more discomfort and pain to the patient. This paper is a review of the scientific publications on the different developed low-cost vein finder prototypes utilizing camera assisted near infrared (NIR) light technology. Methods: Electronic databases were searched online, these included PubMed (PMC), MEDLINE, Science Direct, ResearchGate, and Institute of Electrical and Electronics Engineers (IEEE) Xplore digital library. Specifically, publications with the terms vein finder prototype, NIR technology, vein detection, and infrared imaging were screened. In addition, reference lists were used to further review related publications. Results: Cannulation challenges medical practitioners because of the different factors that can be reduced by the utilization of a vein finder. A limited number of publications regarding the assessment of personnel performing cannulation were observed. Moreover, variations in methodology, number of patients, type of patients according to their demographics and materials used in the assessment of the developed prototypes were noted. Some studies were limited with regard to the actual human testing of the prototype. Conclusions: The development of a low-cost effective near infrared (NIR) vein finder remains in the phase of improvement. Since, it is being challenged by different human factors, increasing the number of parameters and participants/human for actual testing of the prototypes must also be taken into consideration for possible commercialization. Finally, it was noted that publications regarding the assessment of the performance of phlebotomists using vein finders were limited.

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Luminescent κ-Carrageenan-Based Electrolytes Containing Neodymium Triflate

Molecules ◽

10.3390/molecules24061020 ◽

2019 ◽

Vol 24 (6) ◽

pp. 1020 ◽

Cited By ~ 2

Author(s):

S. Nunes ◽

S. Saraiva ◽

R. Pereira ◽

M. Silva ◽

L. Carlos ◽

...

Keyword(s):

Ionic Conductivity ◽

Alkaline Earth ◽

Near Infrared ◽

Low Cost ◽

Earth Metal ◽

Cost Effective ◽

Red Seaweeds ◽

Multi Wavelength ◽

Electrochemical Devices ◽

Uv Visible

In recent years, the synthesis of polymer electrolyte systems derived from biopolymers for the development of sustainable green electrochemical devices has attracted great attention. Here electrolytes based on the red seaweeds-derived polysaccharide κ-carrageenan (κ-Cg) doped with neodymium triflate (NdTrif3) and glycerol (Gly) were obtained by means of a simple, clean, fast, and low-cost procedure. The aim was to produce near-infrared (NIR)-emitting materials with improved thermal and mechanical properties, and enhanced ionic conductivity. Cg has a particular interest, due to the fact that it is a renewable, cost-effective natural polymer and has the ability of gelling in the presence of certain alkali- and alkaline-earth metal cations, being good candidates as host matrices for accommodating guest cations. The as-synthesised κ-Cg-based membranes are semi-crystalline, reveal essentially a homogeneous texture, and exhibit ionic conductivity values 1–2 orders of magnitude higher than those of the κ-Cg matrix. A maximum ionic conductivity was achieved for 50 wt.% Gly/κ-Cg and 20 wt.% NdTrif3/κ-Cg (1.03 × 10−4, 3.03 × 10−4, and 1.69 × 10−4 S cm−1 at 30, 60, and 97 °C, respectively). The NdTrif-based κ-Cg membranes are multi-wavelength emitters from the ultraviolet (UV)/visible to the NIR regions, due to the κ-Cg intrinsic emission and to Nd3+, 4F3/2→4I11/2-9/2.

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Fabrication and Characterization of Near Infrared Molybdenum Disulfide/Silicon Heterojunction Photodetector by Drop Casting Method

10.20944/preprints202104.0119.v1 ◽

2021 ◽

Author(s):

Haroon Rashid ◽

Norhana Arsad ◽

Harith Ahmad ◽

Ahmad Ashrif A. Bakar ◽

Mamun Ibne Reaz

Keyword(s):

Molybdenum Disulfide ◽

Near Infrared ◽

Film Growth ◽

Low Cost ◽

Incident Light ◽

Cost Effective ◽

Optoelectronic Device ◽

Casting Method ◽

Incident Laser Power ◽

Device Applications

In this work, a highly efficient, molybdenum disulfide (MoS2) based near infrared (NIR) heterojunction photodetector is fabricated on a Si substrate using a cost-effective and simple drop casting method. A non-stoichiometric and inhomogeneous MoS2 layer with a S/Mo ratio of 2.02 is detected using energy dispersive X-ray spectroscopy and field emission scanning electron microscope analysis. Raman shifts are noticed at 382.42 cm-1 and 407.97 cm-1, validating MoS2 thin film growth with a direct bandgap of 2.01 eV. The fabricated n-MoS2/p-Si photodetector is illuminated with a 785 nm laser at different intensities, and demonstrate the ability of the photodetector to work in both regions, the forward biased and reverse biased from above 1.5 V and less than -1.0 V. The highest responsivity, R is calculated to be 0.52 A/W while the detectivity D* is 4.08 x 10^10 Jones for an incident light intensity of 9.57 mW/cm2. The minimum rise and fall times are calculated as 1.77 ms and 1.31 ms for an incident laser power of 9.57 mW/cm^2 and 6.99 mW/cm^2 respectively at a direct current bias voltage of 10 V. The demonstrated results are promising for the low-cost fabrication of a thin MoS2 film for photonics and optoelectronic device applications.

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Towards a Low-Cost Mobile Subcutaneous Vein Detection Solution Using Near-Infrared Spectroscopy

The Scientific World JOURNAL ◽

10.1155/2014/365902 ◽

2014 ◽

Vol 2014 ◽

pp. 1-15 ◽

Cited By ~ 18

Author(s):

Simon Juric ◽

Vojko Flis ◽

Matjaz Debevc ◽

Andreas Holzinger ◽

Borut Zalik

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Infrared Imaging ◽

Low Cost ◽

Grey Literature ◽

Cost Effective ◽

Research Direction ◽

Future Research ◽

Pubmed Database

Excessive venipunctures are both time- and resource-consuming events, which cause anxiety, pain, and distress in patients, or can lead to severe harmful injuries. We propose a low-cost mobile health solution for subcutaneous vein detection using near-infrared spectroscopy, along with an assessment of the current state of the art in this field. The first objective of this study was to get a deeper overview of the research topic, through the initial team discussions and a detailed literature review (using both academic and grey literature). The second objective, that is, identifying the commercial systems employing near-infrared spectroscopy, was conducted using the PubMed database. The goal of the third objective was to identify and evaluate (using the IEEE Xplore database) the research efforts in the field of low-cost near-infrared imaging in general, as a basis for the conceptual model of the upcoming prototype. Although the reviewed commercial devices have demonstrated usefulness and value for peripheral veins visualization, other evaluated clinical outcomes are less conclusive. Previous studies regarding low-cost near-infrared systems demonstrated the general feasibility of developing cost-effective vein detection systems; however, their limitations are restricting their applicability to clinical practice. Finally, based on the current findings, we outline the future research direction.

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Low cost infrared and near infrared sensors for UAVs

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xl-1-1-2014 ◽

2014 ◽

Vol XL-1 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

S. T. Aden ◽

J. P. Bialas ◽

Z. Champion ◽

E. Levin ◽

J. L. McCarty

Keyword(s):

Remote Sensing ◽

Near Infrared ◽

Low Cost ◽

Cost Effective ◽

Infrared Sensors ◽

Management Options ◽

Time Saving ◽

Wide Range ◽

Infrared Cameras ◽

Wildland Firefighting

Thermal remote sensing has a wide range of applications, though the extent of its use is inhibited by cost. Robotic and computer components are now widely available to consumers on a scale that makes thermal data a readily accessible resource. In this project, thermal imagery collected via a lightweight remote sensing Unmanned Aerial Vehicle (UAV) was used to create a surface temperature map for the purpose of providing wildland firefighting crews with a cost-effective and time-saving resource. The UAV system proved to be flexible, allowing for customized sensor packages to be designed that could include visible or infrared cameras, GPS, temperature sensors, and rangefinders, in addition to many data management options. Altogether, such a UAV system could be used to rapidly collect thermal and aerial data, with a geographic accuracy of less than one meter.

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A Low-Cost Solution for Automatic Plastic Segregation

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.c5275.029320 ◽

2020 ◽

Vol 9 (3) ◽

pp. 784-788

Keyword(s):

Waste Management ◽

Solid Waste ◽

Real Time ◽

Thermal Imaging ◽

Near Infrared ◽

Solid Waste Management ◽

Collection Efficiency ◽

Plastic Material ◽

Low Cost ◽

Cost Effective

Solid waste management is a universal issue that matters to every single person in the world. The solid waste management system is fundamentally labor intensive with very little collection efficiency. The available automatic plastic segregation techniques are based on thermal imaging and electrostatic properties of materials- these methods are expensive for governments to invest upon, and also to maintain in landfills. In this paper, artificial intelligence techniques are exploited to recognize the sounds of plastics from that of other materials by designing suitable mechanism to produce sound from debris during segregation, the segregation process can be automated with relatively low-cost electronics like System on Chips and audio sensors. With 30,000 recorded samples of noisy plastic and non-plastic material sounds, ANN is trained and was able to successfully detect plastics with 93.5% accuracy in real time. Algorithms were developed in python and real time testing was done on SoC with a mic, which affirms that the proposed method is cost effective when compared to techniques involving image processing, thermal imaging and near infrared spectroscopy.

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ASSESSMENT OF THE PLATELET COUNT IN THE PREGNANT WOMEN IN IGIMS, PATNA, BIHAR

International Journal of Medical and Biomedical Studies ◽

10.32553/ijmbs.v4i2.1185 ◽

2020 ◽

Vol 4 (2) ◽

Author(s):

Tanwi Singh ◽

Anshuman Sinha

Keyword(s):

Platelet Count ◽

Pregnant Women ◽

Screening Test ◽

Low Cost ◽

Medical Science ◽

Cost Effective ◽

Platelet Indices ◽

Increased Risk ◽

Low Platelet Count ◽

Severity Of The Disease

The major risk associated with low platelet count in pregnancy is the increased risk of bleeding during the childbirth or post that. There is an increased blood supply to the uterus during pregnancy and the surgical procedure requires cutting of major blood vessels. Women with thrombocytopenia are at increased risk of losing excessive blood. The risk is more in case of caesarean delivery as compared to vaginal delivery. Hence based on above findings the present study was planned for Assessment of the Platelet Count in the Pregnant Women in IGIMS, Patna, Bihar. The present study was planned in Department of Pathology, Indira Gandhi Institute of Medical Science, Patna, Bihar, India. The present study was planned from duration of January 2019 to June 2019. In the present study 200 pregnant females samples received for the platelet estimation were enrolled in the present study. Clinically platelet indices can be a useful screening test for early identification of preeclampsia and eclampsia. Also platelet indices can assess the prognosis of this disease in pregnant women and can be used as an effective prognostic marker because it correlates with severity of the disease. Platelet count is a simple, low cost, and rapid routine screening test. Hence the data generated from the present study concludes that platelet count can be used as a simple and cost effective tool to monitor the progression of preeclampsia, thereby preventing complications to develop during the gestational period. Keywords: Platelet Count, Pregnant Women, IGIMS, Patna, Bihar, etc.

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