A Novel Chemiluminescence Biosensor Based on Dual Aptamers Bound Nanoparticles with Multi-site Signal Amplification for Sensitive Detection of Carcinoembryonic Antigen

A novel biosensor based on a bio-barcode for the detection of Mycobacterium tuberculosis

Tuberculosis (TB), the second (after COVID-19) deadliest infectious killer, is a chronic infectious disease caused by infection with Mycobacterium tuberculosis (M.T.), where early diagnosis and management are the key to containing the condition. Here, we report a novel biosensor for the detection of M.T. DNA based on magnetic separation, urease catalysis and silicon nanowire field effect transistor (SiNW FET) detection. M.T. DNA is sequence-specifically captured by magnetic nanoparticles and urease-labelled silica nanoparticles simultaneously to form a sandwich complex and urea is catalyzed into ammonium carbonate by urease modified on a sandwich complex. By using SiNW FET, the detection of M.T. DNA is realized indirectly by the detection of ammonium carbonate. The limit of detection (LOD) was determined to be 78.541 fM. The specificity of the biosensor was confirmed by detecting a panel of bacterial species. The utility of the biosensor was demonstrated in real-sample analysis and the recovery study of M.T. DNA was done in the genomic DNA extracted from cultured Mycobacterium tuberculosis. The biosensor holds promise to become a rapid, sensitive and accurate method for clinical diagnosis.

A novel flower-shaped Ag@ZIF-67 chemiluminescence sensor for sensitive detection of CEA

In this work, a chemiluminescence (CL) aptasensor for sensitive carcinoembryonic antigen (CEA) detection was constructed based on the CL system of luminol-H₂O₂-NaOH. Magnetic carbon nanotubes (MCNTs), as the base material, was modified with CEA-aptamer and DNA1, and was combined with the novel flower-shaped Ag@ZIF-67 of modified with DNA2 through the principle of base complementary pairing. CEA combined with aptamer when it existed in the solution. At the same time, MCNTs was adsorbed at the bottom of the container under the influence of external magnetic field, and Ag@ZIF-67 enhanced the CL signal. The CL aptasensor demonstrated high selectivity and sensitivity for CEA in human serum sample with (1-4): a detection limit of 4.53 × 10^-3 ng/mL in case the detection range was 0.05-500 ng/mL. Furthermore, the proposed method had been shown great potential in cancer diagnosis.

Recent Advances in Wearable Biosensors for Non-Invasive Detection of Human Lactate

Lactate, a crucial product of the anaerobic metabolism of carbohydrates in the human body, is of enormous significance in the diagnosis and treatment of diseases and scientific exercise management. The level of lactate in the bio-fluid is a crucial health indicator because it is related to diseases, such as hypoxia, metabolic disorders, renal failure, heart failure, and respiratory failure. For critically ill patients and those who need to regularly control lactate levels, it is vital to develop a non-invasive wearable sensor to detect lactate levels in matrices other than blood. Due to its high sensitivity, high selectivity, low detection limit, simplicity of use, and ability to identify target molecules in the presence of interfering chemicals, biosensing is a potential analytical approach for lactate detection that has received increasing attention. Various types of wearable lactate biosensors are reviewed in this paper, along with their preparation, key properties, and commonly used flexible substrate materials including polydimethylsiloxane (PDMS), polyethylene terephthalate (PET), paper, and textiles. Key performance indicators, including sensitivity, linear detection range, and detection limit, are also compared. The challenges for future development are also summarized, along with some recommendations for the future development of lactate biosensors.

Recent Advances in Electrochemical Aptasensors for Detection of Biomarkers

The early diagnosis of diseases is of great importance for the effective treatment of patients. Biomarkers are one of the most promising medical approaches in the diagnosis of diseases and their progress and facilitate reaching this goal. Among the many methods developed in the detection of biomarkers, aptamer-based biosensors (aptasensors) have shown great promise. Aptamers are promising diagnostic molecules with high sensitivity and selectivity, low-cost synthesis, easy modification, low toxicity, and high stability. Electrochemical aptasensors with high sensitivity and accuracy have attracted considerable attention in the field of biomarker detection. In this review, we will summarize recent advances in biomarker detection using electrochemical aptasensors. The principles of detection, sensitivity, selectivity, and other important factors in aptasensor performance are investigated. Finally, advantages and challenges of the developed aptasensors are discussed.