Fabrication of miniaturized and microfluidic wearable biosensors using 3D bioprinting technology

• Grant number: 23/03483-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: May 01, 2023
• End date: August 31, 2026
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal Investigator: William Reis de Araujo
• Grantee: Guida Hellen Mota do Nascimento
• Host Institution: Instituto de Química (IQ). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 22/03250-7 - Development of portable and cost-effective biosensors for clinical diagnosis of bacterial and viral infections, AP.PNGP.PI

Abstract

Staphylococcus spp., Pseudomonas spp., and Acinetobacter spp. are 3 bacterial respiratory pathogens widely found in the oral cavity of hospitalized patients. Recent studies indicate that saliva can play an important role in the development of pneumonia, for example, acting as a vehicle for bacteria residing in the oral cavity, which can be aspirated into the lungs. In addition, oral anaerobic bacteria were also isolated from patients with ventilator-associated pneumonia, reinforcing the role of the oral microbiota in these infections. Thus, the relevance of salivary analyses as minimally invasive methods for diagnosing bacteria that cause respiratory diseases is highlighted. In this way, the present research project aims to manufacture biosensors coupled to a miniaturized 3D-bioprinted microfluidic device for the detection of bacteria that cause respiratory diseases directly in saliva. The miniaturized bioprinted device will contain a saliva sampling region connected by 3 microchannels that lead to detection zones. The bioprinting technology aims to ensure the biocompatibility and low toxicity of the wearable device for its insertion into the oral cavity of patients, aiming at the passive sampling of saliva and real-time bacteria detection. We will use a colorimetric readout strategy for the detection of Staphylococcus spp., Pseudomonas spp., and Acinetobacter spp using weak immobilization of specific antibodies labeled with chromophores for each of the bacteria on the inner walls of each of the printed microchannels. Thus, as the salivary sample containing the bacteria flows through the microchannels, upon reaching the conjugation regions, interaction with the labeled antibodies will occur and these will be leached by capillarity to a detection zone, where the recognition with the detection antibody will occur by the formation of a "sandwich", revealing the presence of the bacteria by the appearance of color in each of the specific microchannels. In addition to material biocompatibility, the occlusion of the reagents inside the microchannels will provide low general toxicity of the bioassay to the user, as well as adequate conditions for the stabilization of the antibodies, generating more robust immunoassays and with adequate useful life for point-of-care applications. Initially, the devices will be characterized using artificial saliva and after the analytical optimizations and approval of the research ethics committee, the developed biosensors will be applied for the detection of the 3 bacteria in real saliva samples of volunteers and hospital patients to confirm the potentiality of the method.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DE LIMA, LUCAS FELIPE; FERREIRA, ANDRE LOPES; DO NASCIMENTO, GUIDA HELLEN MOTA; CARDOSO, LUANA PEREIRA; DE JESUS, MARCELO BISPO; DE ARAUJO, WILLIAM REIS. Tongue depressor (bio)sensors: A fast decentralized self-testing of salivary biomarkers for personalized medicine. CHEMICAL ENGINEERING JOURNAL, v. 494, p. 13-pg., 2024-06-18. (22/09892-0, 23/03483-4, 23/05204-5, 23/12589-0, 23/06143-0, 23/00246-1, 18/08782-1, 22/03250-7)

BERKHEIMER, ZACHARY A.; TAHIR, ANUM; NORDIN, GREGORY P.; PAIXAO, THIAGO R. L. C.; WOOLLEY, ADAM T.; DO NASCIMENTO, GUIDA H. M.; DE ARAUJO, WILLIAM R.; PRADELA-FILHO, LAURO A.. Extruded filament electrodes for lactate biosensing in continuous-injection paper-based microfluidic devices. BIOSENSORS & BIOELECTRONICS, v. 278, p. 9-pg., 2025-06-15. (18/08782-1, 23/00246-1, 22/11346-4, 21/00205-8, 23/03483-4)