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1.
Anal Chem ; 89(24): 13160-13166, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29131592

RESUMO

In this work, a disposable paper-plastic hybrid microfluidic lab-on-a-chip (LOC) has been developed and successfully applied for the colorimetric measurement of urine by the smartphone-based optical platform using a "UrineAnalysis" Android app. The developed device was cost-effectively implemented as a stand-alone hybrid LOC by incorporating the paper-based conventional reagent test strip inside the plastic-based LOC microchannel. The LOC device quantitatively investigated the small volume (40 µL) of urine analytes for the colorimetric reaction of glucose, protein, pH, and red blood cell (RBC) in integration with the finger-actuating micropump. On the basis of our experiments, the conventional urine strip showed large deviation as the reaction time goes by, because dipping the strip sensor in a bottle of urine could not control the reaction volume. By integrating the strip sensor in the LOC device for urine analysis, our device significantly improves the time-dependent inconstancy of the conventional dipstick-based urine strip, and the smartphone app used for image analysis enhances the visual assessment of the test strip, which is a major user concern for the colorimetric analysis in point-of-care (POC) applications. As a result, the user-friendly LOC, which is successfully implemented in a disposable format with the smartphone-based optical platform, may be applicable as an effective tool for rapid and qualitative POC urinalysis.


Assuntos
Colorimetria/instrumentação , Técnicas Analíticas Microfluídicas , Papel , Plásticos/química , Smartphone , Urinálise/instrumentação , Bilirrubina/urina , Eritrócitos/química , Glucose/análise , Humanos , Concentração de Íons de Hidrogênio , Testes Imediatos , Proteínas/análise , Urobilinogênio/urina
2.
BMC Psychiatry ; 17(1): 281, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28826398

RESUMO

BACKGROUND: Autism spectrum disorders (ASD) are a group of complex neurodevelopmental disorders. The prevalence of ASD in many South Asian countries is still unknown. The aim of this study was to systematically review available epidemiological studies of ASD in this region to identify gaps in our current knowledge. METHODS: We searched, collected and evaluated articles published between January 1962 and July 2016 which reported the prevalence of ASD in eight South Asian countries. The search was conducted in line with the PRISMA guidelines. RESULTS: We identified six articles from Bangladesh, India, and Sri Lanka which met our predefined inclusion criteria. The reported prevalence of ASD in South Asia ranged from 0.09% in India to 1.07% in Sri Lanka that indicates up to one in 93 children have ASD in this region. Alarmingly high prevalence (3%) was reported in Dhaka city. Study sample sizes ranged from 374 in Sri Lanka to 18,480 in India. The age range varied between 1 and 30 years. No studies were found which reported the prevalence of ASD in Pakistan, Nepal, Bhutan, Maldives and Afghanistan. This review identifies methodological differences in case definition, screening instruments and diagnostic criteria among reported three countries which make it very difficult to compare the studies. CONCLUSIONS: Our study is an attempt at understanding the scale of the problem and scarcity of information regarding ASD in the South Asia. This study will contribute to the evidence base needed to design further research and make policy decisions on addressing this issue in this region. Knowing the prevalence of ASD in South Asia is vital to ensure the effective allocation of resources and services.


Assuntos
Povo Asiático/psicologia , Povo Asiático/estatística & dados numéricos , Transtorno do Espectro Autista/epidemiologia , Bangladesh/epidemiologia , Humanos , Índia/epidemiologia , Sri Lanka/epidemiologia
3.
Bioelectrochemistry ; 122: 221-226, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29129601

RESUMO

In this work, a Lab-on-a-Chip (LOC) platform is used to electromagnetically actuate magnetic bead chains for an enhanced immunoassay. Custom-made electromagnets generate a magnetic field to form, rotate, lift and lower the magnetic bead chains (MBCs). The cost-effective, disposable LOC platform was made with a polymer substrate and an on-chip electrochemical sensor patterned via the screen-printing process. The movement of the MBCs is controlled to improve the electrochemical signal up to 230% when detecting beta-type human chorionic gonadotropin (ß-hCG). Thus, the proposed on-chip MBC-based immunoassay is applicable for rapid, qualitative electrochemical point-of-care (POC) analysis.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/análise , Imunoensaio/instrumentação , Dispositivos Lab-On-A-Chip , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Humanos , Imunoensaio/economia , Limite de Detecção , Campos Magnéticos , Imãs/química , Técnicas Analíticas Microfluídicas/economia , Técnicas Analíticas Microfluídicas/instrumentação
4.
Biomed Opt Express ; 8(7): 3317-3328, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28717569

RESUMO

A novel and rapid analysis technique using histogram has been proposed for the colorimetric quantification of blood hematocrits. A smartphone-based "Histogram" app for the detection of hematocrits has been developed integrating the smartphone embedded camera with a microfluidic chip via a custom-made optical platform. The developed histogram analysis shows its effectiveness in the automatic detection of sample channel including auto-calibration and can analyze the single-channel as well as multi-channel images. Furthermore, the analyzing method is advantageous to the quantification of blood-hematocrit both in the equal and varying optical conditions. The rapid determination of blood hematocrits carries enormous information regarding physiological disorders, and the use of such reproducible, cost-effective, and standard techniques may effectively help with the diagnosis and prevention of a number of human diseases.

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