Source: Biosensors, by Mohamed Sharafeldin. AI-generated summary by biochip.com, published . Not independently reviewed.
Key takeaways
- Rapid antigen tests let untrained users analyze nasopharyngeal swabs at home within minutes during the COVID-19 pandemic.
- Electrochemical glucose meters made self-monitoring of blood glucose a standard part of diabetes care after home kits emerged in the 1970s.
- The overview does not establish clinical performance or validation data for newer biosensors targeting cardiovascular disease or cancer.
Chemist Mohamed Sharafeldin of the University of Otago surveys how biosensors have moved testing from specialized laboratories toward homes, clinics, and other point-of-need settings. The COVID-19 pandemic made that shift highly visible, as rapid antigen tests allowed people to analyze nasal swabs in minutes instead of sending samples to a central laboratory. Those tests built on decades of work to create devices that recognize biologically relevant substances and turn that recognition into a readable result. Early pandemic testing relied heavily on polymerase chain reaction, or PCR, a laboratory method that detects genetic material but can require trained staff, costly equipment, and turnaround times ranging from hours to days. Lateral flow devices and rapid antigen tests offered a simpler alternative for some uses, helping testing programs support isolation and contact-tracing measures. The most established biosensor, however, is the blood glucose meter used by people with diabetes. Its success helped establish self-monitoring as a routine part of care and helped launch biosensor research across medicine, food quality control, pharmaceuticals, and border control. Sharafeldin's overview places these devices at the center of a broader push for faster, more individualized health information.
What a biosensor does
A biosensor is a device designed to report on a biological or disease-related condition by detecting an analyte, meaning a substance being measured in a sample. It can be thought of as a tiny interpreter: one part recognizes a target such as a protein, nucleic acid, or metabolite, while another part converts that interaction into a result a user can read.
The practical goal is to let a person test a sample where it is needed, whether at home or in a health care facility. By reducing the need to transport samples to a central laboratory, biosensors can provide information quickly enough to support clinical assessment and decisions about managing a health condition.
COVID-19 made rapid testing familiar
During the COVID-19 outbreak, rapid analysis became essential for reducing delays and limiting further transmission. PCR initially served as the well-established nucleic acid test, but it depended on centralized facilities, trained operators, and expensive instruments.
Rapid antigen tests, also called lateral flow devices, changed the experience of testing for many people. Untrained users could analyze nasopharyngeal swabs at home within minutes, making test-and-trace and test-and-release programs more practical in public life.
The glucose meter set the standard
The glucose sensor, or glucometer, remains one of the first commercially available and most successful biosensors. It measures glucose in blood obtained through a finger prick, giving people with diabetes a direct way to monitor a value that matters to their daily care.
Before home glucose testing, glucose could be measured in urine using Benedict's reagent, a copper-based mixture that detects reducing sugars. That approach required heating and could be disrupted by other reducing chemicals, whereas electrochemical glucose sensors offered faster, more sensitive glucose measurement.
From urine tests to self-monitoring
The arrival of home glucose testing kits in the 1970s marked a major change in diabetes care. It established self-monitoring of blood glucose, often shortened to SMBG, as a standard approach that allowed patients to measure glucose without depending entirely on a clinical laboratory.
Electrochemical sensors work by translating a chemical event into an electrical signal. Like a smoke detector that turns a small change in the air into an alarm, a glucose meter turns the presence of glucose in a blood sample into a numerical reading that can guide action.
Targets for precision medicine
Biosensors are being developed for disease diagnostics and point-of-care health monitoring, meaning testing performed near the patient rather than at a distant laboratory. Their appeal has grown alongside medicines aimed at specific biochemical pathways, because patients can differ genetically and physiologically in ways that affect which treatment is most suitable.
These devices can be designed to look for biomarkers, measurable signs of a biological state, including proteins, nucleic acids, and metabolites that are abnormally expressed as disease progresses. In principle, identifying such targets can help indicate disease stage, show how a patient is responding to therapy, and inform more personalized interventions.
Why This Matters
Fast, usable testing can change who has access to health information and when they receive it. Rather than waiting for a sample to travel through a testing system, a biosensor can bring a result closer to the patient, potentially enabling earlier detection, closer monitoring, and quicker clinical decisions.
The technology also reaches beyond human health. Sharafeldin identifies biomedical applications, pharmaceutical work, food quality control, drug control, and border control as areas shaped by biosensor development, reflecting the wide value of devices that can identify a specific biological or chemical signal rapidly.
What comes next
The next challenge is to pair the convenience demonstrated by home glucose meters and rapid antigen tests with tests for a wider range of clinically meaningful biomarkers. Progress in microfluidics, which uses tiny channels to handle small volumes of liquid, and in electrochemical and optical detection could help make sensitive sensors more scalable and easier to use outside conventional laboratories.
Topics: Biosensors · Diabetes & metabolism · Diagnostics & precision medicine · Drug development & safety · Infectious diseases
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