Paper/Polymer Hybrid Microfluidic Biochips for Infectious Disease Diagnosis

Infectious diseases frequently cause public health concerns and they often occur in high-poverty regions. Hence, a simple and low-cost method is in great need for immediate and early diagnosis of infectious diseases. Recently, microfluidic lab-on-a-chip offers a unique opportunity for various biomedical applications. Since different chip substrates have different advantages and limitations, hybrid devices can draw more benefits from different substrates. Therefore, we have developed three paper/polymer hybrid microfluidic biochips integrated with loop-mediated isothermal amplification (LAMP) for high-sensitivity infectious disease diagnosis. We for the first time developed a low-cost paper/polydimethylsiloxane (PDMS) hybrid microfluidic biochip for rapid, sensitive and instrument-free detection of a main meningitis-causing bacterium, N. meningitidis. The hybrid microfluidic biochip with paper inside enabled stable testing results over a much longer period of time than a paper-free microfluidic biochip. Although no any specialized instruments were used, the limit of detection of 3 copies per LAMP zone for N. meningitidis was readily achieved, which was comparable to costly qPCR. We further demonstrated the broader application of our microfluidic approach with high sensitivity and specificity by testing the whooping cough-causing bacterium, B. pertussis, in 100 human clinical samples. On the basis of singleplexed pathogen detection, we developed another paper/PDMS hybrid microfluidic biochip for simultaneous detection of three pathogens, N. meningitidis, S. pneumoniae and Hib, which cause most of the bacterial meningitis. At last, we developed a paper/poly(methyl methacrylate) (PMMA) hybrid CD-like microfluidic SpinChip that integrated with graphene oxide (GO) functionalized nanosensors for the quantitative multiplex LAMP (mLAMP) detection of infectious diseases. Paper in this hybrid system facilitated the simple integration of nanosensors on the SpinChip. These low-cost paper/polymer hybrid microfluidic biochips have great potential for point-of-care (POC) infectious diseases diagnosis, especially in low-resource settings such as physicianâ??s office and developing nations

A versatile PDMS/paper hybrid microfluidic platform for rapid and sensitive infectious diseases diagnosis

Bacterial meningitis is a serious health concern worldwide. Given that meningitis can be fatal and many meningitis cases occurred in high-poverty areas, a simple, low-cost, highly sensitive method is in great need for immediate and early diagnosis of meningitis. Herein, we report a versatile and cost-effective polydimethylsiloxane (PDMS)/paper hybrid microfluidic device integrated with loop-mediated isothermal amplification (LAMP) for the rapid, sensitive, and instrument-free detection of the main meningitis-causing bacteria, Neisseria meningitidis (N. meningitidis). The introduction of paper into the microfluidic device for LAMP reactions enables stable test results over a much longer period of time than a paper-free microfluidic system. This hybrid system also offers versatile functions, by providing not only on-site qualitative diagnostic analysis (i.e., a yes or no answer), but also confirmatory testing and quantitative analysis in laboratory settings. The limit of detection of N. meningitidis is about 3 copies per LAMP zone within 45 min, close to single-bacterium detection sensitivity. In addition, we have achieved simple pathogenic microorganism detection without a laborious sample preparation process and without the use of centrifuges. This low-cost hybrid microfluidic system provides a simple and highly sensitive approach for fast instrument-free diagnosis of N. meningitidis in resource-limited settings. This versatile PDMS/paper microfluidic platform has great potential for the point of care (POC) diagnosis of a wide range of infectious diseases, especially for developing nations

A paper/polymer hybrid CD-like microfluidic SpinChip integrated with DNA-functionalized graphene oxide nanosensors for multiplex qLAMP detection

© 2017 The Royal Society of Chemistry. A paper/poly(methyl methacrylate) (PMMA) hybrid CD-like microfluidic SpinChip integrated with DNA probe-functionalized graphene oxide (GO) nanosensors was developed for multiplex quantitative LAMP detection (mqLAMP). This approach can simply and effectively address a major challenging problem of multiplexing in current LAMP methods

Rapid and Accurate Diagnosis of the Respiratory Disease Pertussis on a Point-of-Care Biochip

Background: Pertussis is a highly contagious respiratory disease caused by the bacterium Bordetella pertussis (B. pertussis). The infection is difficult to diagnose especially in underserved or resource-limited areas. We developed a low-cost and instrument-free diagnostic method for rapid and accurate detection of B. pertussis on a point-of-care (POC) testing device. Methods: We developed a paper/polymer hybrid microfluidic biochip integrated with loop-mediated isothermal amplification (LAMP) method for the rapid and accurate detection of B. pertussis. This microfluidic approach was validated by testing 100 de-identified remnant clinical nasopharyngeal swabs and aspirates, which were confirmed to be either positive or negative for B. pertussis by a validated real-time PCR assay at the Children's Hospital Los Angeles. Findings: The instrument-free detection results could be successfully read by the naked eye within 45 min with a limit of detection (LOD) of 5 DNA copies per well. Our optimized bacterial lysis protocol allowed the direct testing of clinical samples without any complicated sample processing/preparation (i.e. DNA extraction) or the use of any equipment (e.g. centrifuges). The validation of the microfluidic approach was accomplished by testing 100 clinical samples. High sensitivity (100%) and specificity (96%) with respect to real-time PCR were achieved. Interpretation: This microfluidic biochip shows great potential for point-of-care disease diagnosis in various venues including schools and physician's offices, especially in low-resource settings in developing nations. Funding: NIH/NIAID under award number R21AI107415, NIH RCMI Pilot Grant, the Philadelphia Foundation, the Medical Center of the Americas Foundation. Keywords: Pertussis diagnosis, Point-of-care detection, Microfluidic biochip, Whooping cough, Loop-mediated isothermal amplification (LAMP

Multiplexed instrument-free meningitis diagnosis on a polymer/paper hybrid microfluidic biochip

© 2016 Elsevier B.V. Neisseria meningitidis (N. meningitidis), Streptococcus pneumoniae (S. pneumoniae), and Haemophilus influenzae type b (Hib) are three most common pathogens accounting for most bacterial meningitis, a serious global infectious disease with high fatality, especially in developing nations. Because the treatment and antibiotics differ among each type, the identification of the exact bacteria causing the disease is vital. Herein, we report a polymer/paper hybrid microfluidic biochip integrated with loop-mediated isothermal amplification (LAMP) for multiplexed instrument-free diagnosis of these three major types of bacterial meningitis, with high sensitivity and specificity. Results can be visually observed by the naked eye or imaged by a smartphone camera under a portable UV light source. Without using any specialized laboratory instrument, the limits of detection of a few DNA copies per LAMP zone for N. meningitidis, S. pneumoniae and Hib were achieved within 1 h. In addition, these three types of microorganisms spiked in artificial cerebrospinal fluid (ACSF) were directly detected simultaneously, avoiding cumbersome sample preparation procedures in conventional methods. Compared with the paper-free non-hybrid microfluidic biochip over a period of three months, the hybrid microfluidic biochip was found to have a much longer shelf life. Hence, this rapid, instrument-free and highly sensitive microfluidic approach has great potential for point-of-care (POC) diagnosis of multiple infectious diseases simultaneously, especially in resource-limited settings