Bioassays

Bioassays encompass experimental procedures that quantify the potency, efficacy or concentration of biologically active substances by measuring their effects on living cells, tissues or organisms. Historically, such assays have underpinned pharmaceutical standardisation and environmental risk assessment, evolving from in vivo animal studies to sophisticated in vitro systems. Modern bioassays range from cytogenetic tests—such as the micronucleus assay, which measures chromosomal damage in proliferating cells—to high-throughput biosensor platforms that couple enzymatic recognition elements to electrochemical or optical transducers. Key applications include genotoxicity screening, drug candidate profiling and point-of-care diagnostics. Advances in microfluidics, nanomaterials and machine-learning have accelerated assay miniaturisation and multiplexing, facilitating rapid, quantitative readouts from minute sample volumes. Despite this progress, challenges remain in assay interoperability, standardisation and minimisation of matrix interferences. Continued integration of biological and engineering disciplines promises to expand the reach of bioassays in global health, environmental surveillance and personalised medicine.

Research from Nature Portfolio

Studies of chromosomal stability in medical professionals exposed to low-dose ionising radiation have revealed increased frequencies of micronuclei and chromosomal aberrations in peripheral blood lymphocytes of interventional radiologists. These findings underscore the micronucleus assay’s role in biodosimetry and long-term monitoring of genotoxic risk under chronic exposure. Complementing these occupational studies, investigation of genomic instability in urothelial cell carcinoma patients has validated simultaneous scoring of micronuclei, nucleoplasmic bridges and nuclear buds across multiple cell types, including urothelial and buccal cells. Enhanced detection of these biomarkers offers a minimally invasive approach to stratifying cancer risk and tumour progression.

Research from all publishers

A new multiplex micronucleus protocol integrates imaging flow cytometry with staining for γH2AX, p53 and mitotic markers, providing rapid, automated discrimination of clastogenic versus aneugenic modes of action in human lymphoblastoid cells. This high-content assay reduces false positives and accelerates mechanistic profiling of chemical genotoxins. In metabolic sensing, a one-enzyme amperometric device for L-arginine couples arginine oxidase with peroxidase-like nanozymes on a graphite electrode, delivering a broad linear range and low micromolar detection limits in pharmaceutical and food matrices. Meanwhile, pulsed-laser-fragmented carbon quantum dots functionalised with aminophenylboronic acid have emerged as non-enzymatic fluorescent probes for saliva-based glucose assays, achieving sub-millimolar sensitivity and robust performance in complex biological fluids.

Bioassays publication trend

The graph below shows the total number of articles in bioassays across all publications each year (not limited to Nature Index journals).

Technical terms

Bioassay: An experimental procedure that uses biological responses to measure the potency or concentration of an analyte.

Micronucleus: A small extranuclear body containing chromosomal fragments or whole chromosomes that failed to segregate during mitosis.

Clastogenic: Pertaining to agents that induce structural chromosome breaks, often resulting in fragment-based micronuclei.

Aneugenic: Describing substances that disrupt mitotic spindle function, leading to whole-chromosome missegregation into micronuclei.

Amperometric biosensor: A device that transduces enzymatic or cellular biochemical reactions into a measurable electric current under a fixed potential.

Nanozyme: A nanomaterial with intrinsic enzyme-like catalytic activity, employed to enhance biosensor signal generation.

Ratiometric sensing: A measurement approach that uses the ratio of two fluorescence signals to correct for environmental variations and probe concentration.

Molecular rotor: A fluorescent molecule whose emission intensity or lifetime correlates with microviscosity due to restricted intramolecular rotation.

References

1. Effects of low-dose ionizing radiation on genomic instability in interventional radiology workers. Scientific Reports (2023).
2. The frequencies of micronuclei, nucleoplasmic bridges and nuclear buds as biomarkers of genomic instability in patients with urothelial cell carcinoma. Scientific Reports (2018).
3. A multi-biomarker micronucleus assay using imaging flow cytometry. Archives of Toxicology (2024).
4. Amperometric Biosensors for L-Arginine Determination Based on L-Arginine Oxidase and Peroxidase-Like Nanozymes. Applied Sciences (2021).
5. Pulsed laser fragmentation synthesis of carbon quantum dots (CQDs) as fluorescent probes in non-enzymatic glucose detection. Applied Surface Science (2024).