About

Professor Haim H. Bau is a principal investigator in the field of Micro and Nano Fluidics at the University of Pennsylvania. The webpage indicates his association with the department and his role as a leading researcher in this specialized area. The page also lists his colleagues, students, and research personnel, highlighting his active involvement in guiding research and academic activities within this domain. No additional biographical details, research focus, or background information are provided on the page.

Research topics

• Virology
• Biology
• Pathology
• Medicine
• Genetics
• Molecular biology
• Computer Science
• Immunology
• Chemistry
• Bioinformatics
• Internal medicine
• Materials science
• Veterinary medicine
• Computational biology
• Biochemistry
• Chromatography

Selected publications

• Smartphone-Linked and Electricity-Free Platforms for Rapid Colorimetric Molecular Detection of Poultry Respiratory Viruses at the Point of Need

  Biosensors · 2025-09-24

  articleOpen accessSenior author

  Efficient control measures for respiratory diseases in humans and farm animals require accurate, specific, and rapid diagnostics. Traditional PCR-based molecular diagnostics are restricted to centralized laboratories, which results in significant, potentially catastrophic delays in test results. A case in point is the recent avian flu outbreak, which has culled more than 280 million poultry birds worldwide (over 157 million in the USA alone) since 2022; has spread to other farm animals, such as cattle; has further heightened the risk of a human pandemic; and threatens food security. To enable molecular diagnosis of bird respiratory diseases at the point of need, we employ loop-mediated isothermal amplification (LAMP) in two platforms: (A) portable devices linked to a smartphone and (B) an inexpensive, disposable, electricity-free, instrument-free device with closed-tube, colorimetric detection that can be produced with minimal resources. Smartphone integration offers an unexplored opportunity for spatiotemporal disease mapping, equipping policymakers with critical data for outbreak control. Our assays demonstrated 100% sensitivity and specificity compared to the gold standard, lab-based, quantitative PCR (qPCR). We tested contrived samples of the avian flu H5N1 virus, laryngotracheitis virus (ILTV), and infectious bronchitis virus (IBV) spiked into clinical samples, achieving a detection sensitivity adequate for early infection diagnosis in under 45 min. The test is simple, requires minimal training, and can be performed without refrigeration, making it well-suited for resource-limited settings.

  PublisherOA PDFDOI

• A self-heating, multi-channel slider cassette for innovative point-of-care molecular diagnostics from whole blood samples

  Biosensors and Bioelectronics · 2025-09-06 · 1 citations

  articleOpen accessSenior author
  PublisherOA PDFDOI

• Onsager coefficients for liquid metal flow in a conduit under a magnetic field

  Physics of Fluids · 2025-07-01

  articleOpen accessSenior author

  We analyze the flow of room and near room-temperature liquid metals in shallow, long rectangular conduits with two insulating and two perfectly conducting walls under a uniform magnetic field perpendicular to the flow direction and the insulating surfaces, focusing on moderate Hartmann numbers. A pressure gradient and Lorentz body forces may drive or oppose the flow. We derive explicit expressions for the Onsager coefficients that relate the flow rate and electric current on the one hand to the potential difference across electrodes and the pressure gradient on the other hand. We further demonstrate that these coefficients satisfy Onsager–Casimir reciprocity. These simplified expressions provide a convenient framework for analyzing, optimizing, and controlling magnetohydrodynamic (MHD) machines operating with liquid metals in applications such as power conversion, energy harvesting, pumping, actuation, valving, breaking, and sensing without moving components.

  PublisherOA PDFDOI

• Self-actuated microfluidic chiplet for two-stage multiplex nucleic acid amplification assay

  Lab on a Chip · 2024-01-01 · 1 citations

  articleOpen accessSenior authorCorresponding

  Effective diagnosis of comorbidities and infectious diseases that present similar symptoms requires point-of-need assays capable of co-detecting and differentiating among multiple co-endemic pathogens to enable timely, precision medicine and effective control measures. We previously developed a two-stage isothermal amplification assay dubbed Penn-RAMP to address this need. Penn-RAMP's first stage comprises a recombinase polymerase amplification (RPA), which amplifies all targets of interest in a single reaction chamber for a short duration. The RPA amplicons are then aliquoted into multiple loop-mediated isothermal amplification (LAMP) reaction chambers, each customized with pre-dried primers to amplify a single target or a group of targets. To enable Penn-RAMP at the point of need, we describe here a self-actuated Penn-RAMP chiplet that accommodates the Penn-RAMP assay. Our chiplet employs temperature-controlled phase change valves and capillary valves to self-aliquot first-stage amplicons into multiple (five) second-stage reaction chambers and to seal these chambers. The functionality of our device is demonstrated by co-detecting plant pathogens. The analytical performance of our chiplet is comparable to that of the benchtop Penn-RAMP assay and surpasses that of standalone LAMP assays. Our self-actuated chiplet can be operated standalone with purified nucleic acids or as the downstream amplification module of a sample preparation cassette.

  PublisherDOI

• Molecular Detection of Respiratory Tract Viruses in Chickens at the Point of Need by Loop-Mediated Isothermal Amplification (LAMP)

  Viruses · 2024-08-03 · 10 citations

  reviewOpen accessSenior author

  Accurate and timely molecular diagnosis of respiratory diseases in chickens is essential for implementing effective control measures, preventing the spread of diseases within poultry flocks, minimizing economic loss, and guarding food security. Traditional molecular diagnostic methods like polymerase chain reaction (PCR) require expensive equipment and trained personnel, limiting their use to centralized labs with a significant delay between sample collection and results. Loop-mediated isothermal amplification (LAMP) of nucleic acids offers an attractive alternative for detecting respiratory viruses in broiler chickens with sensitivity comparable to that of PCR. LAMP's main advantages over PCR are its constant incubation temperature (∼65 °C), high amplification efficiency, and contaminant tolerance, which reduce equipment complexity, cost, and power consumption and enable instrument-free tests. This review highlights effective LAMP methods and variants that have been developed for detecting respiratory viruses in chickens at the point of need.

  PublisherOA PDFDOI

• Applications of Magneto Electrochemistry and Magnetohydrodynamics in Microfluidics

  Magnetochemistry · 2022-10-26 · 33 citations

  articleOpen access1st authorCorresponding

  Magnetic fields affect electrolytes in diverse ways. This paper focuses on the interactions among electric, magnetic, and flow fields and the applications of the resulting phenomena in microfluidics. When an electrical current is transmitted in an electrolyte in the presence of an external magnetic field, a Lorentz body force results, which may induce pressure gradients and fluid motion—magnetohydrodynamics (MHD). The resulting advection is used to pump fluids, induce/suppress flow instabilities, and control mass transfer in diverse electrochemical processes. When an electrolyte flows in the presence of a magnetic field, electromotive force (emf) is induced in the electrolyte and can be used for flow metering, hydrogen production, and energy conversion. This review describes the governing equations for modeling MHD flows in electrolytes and MHD phenomena and applications relevant to microfluidic systems, such as the use of MHD to pump and stir fluids, propel swimmers, and control fluid flow in fluidic networks without any mechanical components. The paper also briefly assesses the impact of magnetic resonance imaging (MRI) on blood flow. MHD in electrolytes is a highly interdisciplinary, combining electrokinetics, fluid mechanics, electrochemistry, and Maxwell equations.

  PublisherOA PDFDOI

• Sensitive, Single-Pot, Two-Stage Assay for Hepatitis Viruses

  Analytical Chemistry · 2022-01-13 · 17 citations

  articleOpen accessSenior author

  When left untreated, hepatitis B virus (HBV) and hepatitis C virus (HCV) infections may cause severe illnesses. Since these infections remain asymptomatic for many years, routine screening of populations at risk is critical for therapy initiation. The current standard of care mandates a screening antibody test for HCV, followed by a confirmatory laboratory-based molecular test and treatment. Multiple visits to the clinic are inconvenient, and many patients fail to follow up. To address this challenge, we have developed sensitive, two-stage, isothermal molecular (Penn-RAMP) point-of-care tests to enable test and treat strategy. Penn-RAMP's first stage is comprised of recombinase polymerase amplification (RPA), while its second stage is comprised of loop-mediated isothermal amplification (LAMP). Penn-RAMP is more sensitive than LAMP or RPA alone. We designed a custom pre-LAMP buffer to maximize the volume of RPA products that can be added to the LAMP reaction mix without inhibition and forward and backward primers. Penn-RAMP was implemented in a single pot comprised of two compartments separated by a thermally removable barrier. RAMP's first stage is carried out above the barrier at the RPA incubation temperature. When the pot is heated to the LAMP incubation temperature, the barrier melts away, and the RPA reaction volume mixes with the pre-LAMP buffer, facilitating second-stage amplification. This entire process can be carried out with minimal instrumentation. Our HBV and HCV tests detect, respectively, as few as 10 and 25 virions within 30 min. The viral load can be estimated based on signal threshold time.

  PublisherOA PDFDOI

• Molecular and pathological characterization of natural co-infection of poultry farms with the recently emerged Leucocytozoon caulleryi and chicken anemia virus in Egypt

  Tropical Animal Health and Production · 2022-02-08 · 8 citations

  article
  PublisherDOI

• Manually-operated, slider cassette for multiplexed molecular detection at the point of care

  Sensors and Actuators B Chemical · 2022-07-11 · 15 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Editorial: Rapid detection of fungi, microbial, and viral pathogens based on emerging biosensing technology

  Frontiers in Bioengineering and Biotechnology · 2022-11-17 · 1 citations

  editorialOpen accessSenior author

  Fungi, microbial, and viral pathogens have been constantly posing serious threats to human society over the past centuries. Notorious examples in history that claimed millions of innocent lives, like the Plague of Justinian in 541 AD, the Black Death in 1347, the Italian Plague in 1629-1631, the Great Plague of London during the 16th and 17th centuries, the Spanish Flu in 1918, and recent COVID-19 pandemic that started in 2019, all resulted from either bacterium or virus outbreaks. However, the adverse situation had never been overturned until the second industrial resolution in the late 19th century and early 20th century that brought up immense science advances. The rapidly progressive technology, for the first, imparted humans some powerful weapons to win the unconventional war on the invisible battlefields. The comprehensive understanding of microbiology renders the science behind the microbes and leads researchers to decipher more traits about their weakness and strength. In the 1990s, the emerging microfabrication became the first cornerstone to bring the lab-on-a-chip style biosensing technology from theory to reality. The central concept is to seek early medical treatments by early diagnosis. Recently, numerous research efforts have been made in mechanical, optical, electrical, biochemical aspects, making the sensing technology more accurate, sensitive, specific, compact, cost-effective, and rapid than their past counterparts. Electrochemistry has been long adopted as a label-free means in most biochemical detections Their simple integration

  PublisherOA PDFDOI

Recent grants

• Multiplexed point-of-care molecular detection for multiple infections in co-endemic settings

  NIH · $443k · 2017–2021

• NIH Grant R21DE026700

  NIH · $443k · 2019

• GOALI: Real Time, Nanoscale Imaging of Electrochemistry and Electroplating in Liquid Media

  NSF · $282k · 2011–2014

• NIH Grant R03AG042690

  NIH · $74k · 2015

• Point of Care Molecular Detection of Vector-Borne Pathogens

  NIH · $443k · 2018–2022

Frequent coauthors

• Michael G. Mauk

  University of Pennsylvania

  73 shared

• David M. Raizen

  University of Pennsylvania

  40 shared

• Changchun Liu

  UConn Health

  39 shared

• Jinzhao Song

  39 shared

• Jinzhou Yuan

  Research Institute of Dallas

  39 shared

• Mohamed El‐Tholoth

  Higher Colleges of Technology

  31 shared

• Joseph M. Grogan

  Griffith University

  26 shared

• Howard H. Hu

  21 shared

Labs

• Micro and Nano FluidicsPI

Education

• Ph.D., Mechanical Engineering

  University of California, Berkeley

  1989

• M.S., Mechanical Engineering

  University of California, Berkeley

  1985

• B.S., Mechanical Engineering

  University of California, Berkeley

  1983