Luminescence-based cell viability testing.

A novel AIEgen-Based probe Integrated with split aptamer Conjugates for adenosine triphosphate detection in beer.

Graphene foam field-effect transistor for ultra-sensitive label-free detection of ATP

A microfluidic device for adenosine triphosphate (ATP) was checking of fish freshness. Sample solutions containing ATP and the other solution containing an enzyme substrate were handled in the form of plugs formed in a network of flow channels. To simplify the structure and procedure for mixing solutions, a wider portion was formed in a flow channel to merge the plugs. A row of plugs were ejected from each of three branched flow channels, merged at the wider portion, and transported to an ATP biosensor located in the lower stream. ATP was detected using two enzymatic reactions involving glycerol kinase (GK) and glycerol-3-phosphate oxidase (G3PO). The current observed with solutions of three different ATP concentrations showed different values, demonstrating that the device can be used for multi-point sensing. Furthermore, the detection of ATP in extracts from tuna was carried out and a distinct increase in current was observed as in the case of standard solutions.

Effect of vitrification and thawing on human oocyte ATP concentration

Dynamic Changes in Cytosolic and Mitochondrial ATP Levels in Pancreatic Acinar Cells

Adenosine triphosphate (ATP) is a critical intracellular energy currency that plays a key role in various cellular processes and is closely associated with numerous diseases. Similarly, biothiols such as glutathione (GSH), cysteine (Cys), and homocysteine (Hcy) are integral to many physiological and pathological processes due to their strong redox properties. Simultaneous discrimination and detection of ATP and biothiols offer valuable insights into the pathogenesis of conditions such as epilepsy and liver injury. This study introduces the first fluorescent probe, BCR, designed for multifunctional detection of ATP, GSH, Hcy, and Cys. With outstanding optical properties, excellent biocompatibility, high selectivity, and superior sensitivity, probe BCR enables effective imaging of ATP and biothiol dynamics in vivo. Moreover, probe BCR successfully visualizes changes in ATP, GSH, Hcy, and Cys levels in a PTZ‐induced epileptic zebrafish model and an APAP‐induced mouse liver injury tissue section model. These findings underscore the significant potential of probe BCR for early disease diagnosis and therapeutic applications.

Adenosine triphosphate (ATP) is crucial for cellular activity. The need for ATP detection in the field of biomedicine is rapidly increasing. Several biosensor-based approaches have been developed as a result of the growing demand for ATP detection. An electrolyte-insulator-semiconductor (EIS) sensor is a type of field-effect device that has the ability to detect surface-potential changes with a specific level of sensitivity. In this study, a label-free ATP detection biosensor based on poly(amidoamine)-modified EIS sensors was developed, in which an ATP-sensitive aptamer (Apt) was utilized as the sensitive element and the EIS sensor was used as the transducer. It is possible to monitor the binding of charged molecules, such as aptamers using EIS sensors in a label-free manner with a straightforward setup. To improve the coupling efficiency of Apt with the EIS sensor, a positively charged polyelectrolyte, i.e., poly (amidoamine) (PAMAM) dendrimers, was utilized to modify the surface of the EIS sensors to attach the negatively charged Apt through electrostatic attraction. The adsorptive binding of Apt and ATP results in a change in the capacitance of the EIS sensor. During the process of surface modification, the electrochemical measurements of capacitance-voltage (C-V) curves and constant-capacitance (ConCap) characteristics were utilized as indicators for the corresponding processes of EIS sensor surface modification. The measurement results indicated that this biosensor was able to detect ATP with high sensitivity and good specificity. The detection range of ATP was from 0.1 nM to 100 nM and the detection limit was as low as 0.12 nM. This biosensor has the potential to be utilized in the detection of ATP in the surrounding microenvironment of cells and tissues, with promising prospects for application in the field of biomedicine such as energy and metabolism monitoring of cells and tissues.

In the present study, based on multifunctional Dual-Hairpin DNA structure, a simple, fast and high sensitive assay for the detection of DNA, thrombin and adenosine triphosphate (ATP) was demonstrated. DNA sequence labeled with methylene blue (MB), which was designed as single-stranded DNA (ssDNA) matching with target DNA, thrombin, or ATP aptamer, hybridized to the adjunct probe and formed the dual-hairpin structure on the electrode. With the hybridization of adjunct probe and the hairpin-like capture probe in the stem region, the dual-hairpin was formed with outer and inner hairpins. By the conjugation of the target probe with the adjunct probe in the outer hairpin, the adjunct probe divorced from the dual-hairpin structure. The adjunct probe with signal molecules MB, attaching near or divorcing far from the electrode, produced electrochemical signal change and efficient electron transfer due to the fact that it was in proximity to the electrode. However, upon hybridization with the perfect match target, the redox label with the target probe was forced away from the modified electrode, thus resulting in the change of the Dual-Hairpin DNA conformation, which enables impedance of the efficient electron transfer of MB and, consequently, a detectable change of the electrochemical response. In addition, another highlight of this biosensor is its regenerability and stability owing to the merits of structure. Also, based on this Dual-Hairpin platform, the detection limits of DNA, thrombin, and ATP were 50 nM, 3 pM, and 30 nM, respectively. Moreover, this pattern also demonstrated excellent regenerability, reproducibility, and stability. Additionally, given to its ease-of-use, simplicity in design, easy operations, as well as regenerability and stability, the proposed approach may be applied as an excellent design prompter in the preparation of other molecular sensors.

Antifouling aptasensor for the detection of adenosine triphosphate in biological media based on mixed self-assembled aptamer and zwitterionic peptide

Pathogens such as porcine epidemic diarrhea virus (PEDV), porcine reproductive and respiratory syndrome (PRRSV), and E. coli are known to spread by contaminated vehicles and equipment. Pork producers have adopted trailer wash policies where each trailer is washed, disinfected, and dried before it can return to a farm. Cleanliness of livestock trailers after washing is determined by visual inspection rather than any objective method. Adenosine triphosphate (ATP) bioluminescence is used in many industries to provide real-time feedback on surface cleanliness through the detection of ATP from organic sources. That same technology may provide trailer wash facilities a way of objectively characterizing a livestock trailer's suitability to return to a farm after washing. Two ATP luminometers (3M Clean-Trace and Neogen AccuPoint) were used to estimate the correlation between ATP bioluminescence readings and aerobic bacterial plate counts (APCs) from sampled surfaces and to determine locations within a livestock trailer that can accurately estimate surface cleanliness. Five locations in livestock trailers were evaluated. Those locations included the nose access door (NAD), back door flush gate, rear side access door (RSAD), belly flush gate (BFG), and belly side access door (BSAD). There was a positive log-log association between the two luminometers (r = 0.59, P < 0.01). Every log unit increase in one unit, resulted in a 0.42 log increase (P < 0.01) in the other unit. ATP can come from bacteria, yeasts, molds, and manure. There was a poor association (r ≥ 0.10, P ≥ 0.02) between APCs and the ATP luminometers. Still, an increase in relative light units (RLUs) resulted in a corresponding increase in colony-forming units. The greatest area of surface contamination measured by APC was the NAD. RLUs were also greater in the NAD compared to the RSAD, the BFG, and the BSAD (P ≤ 0.01). Because APCs and luminometer RLUs provided similar outcomes, statistical process control charts were developed to determine control limits for RLUs. This provides real-time feedback to trailer wash workers in determining cleanliness outcomes for livestock trailers. These data suggest that ATP bioluminescence can be a reliable method to monitor cleaning effectiveness in livestock trailers. Bioluminescence is a monitoring tool that should be used in conjunction with microbial methods to monitor procedures for cleaning and disinfection.

Triple negative breast cancer (TNBC) affects women worldwide with a higher incidence in minority populations. Patients with TNBCs often have poorer prognoses in comparison to other breast cancer sub-types due to a lack of effective therapeutic options. Chemotherapy and immunotherapy are the only effective treatments, but these modalities generally result in short-term response. Therefore, there is a need to identify additional therapies to intensify the chemotherapeutic response in TNBC. When cancer cells are exposed to chemotherapy, they release adenosine triphosphate (ATP) into the extracellular space. Extracellular ATP is degraded by CD39 (E-NTPDase) to adenosine diphosphate (ADP) and then adenosine monophosphate (AMP), and AMP is broken down to adenosine by CD73. We examined the potential role of extracellular ATP in chemotherapy- induced cancer cell death. We hypothesized that extracellular ATP sensitizes TNBC cells to chemotherapy and that ATP degrading enzymes such as CD39 and CD73 attenuate this effect. TNBC MDA-MB 231, MDA-MB 468, and Hs 578t cell lines were treated with the chemotherapeutic agent paclitaxel for different time courses. Extracellular ATP was measured via the ATPlite 1step luminescence assay, and cell viability was assessed by applying PrestoBlue HS cell viability reagent. Paclitaxel-treated TNBC cell lines revealed a dose-dependent increase in extracellular ATP release in the presence of an inhibitor of CD39 (POM-1), accompanied by a dose-dependent decrease in cell viability. In addition, the general P2X receptor (P2RX) inhibitor iso-PPADS and the P2RX7 specific inhibitor (A438079) were added separately to observe if the P2X receptors are necessary for the release of ATP upon paclitaxel treatment. After paclitaxel treatment, TNBC cell lines showed a decline in the amount of ATP released with the addition of the inhibitors iso-PPADS and A438079. Treatment of non-tumorigenic immortalized MCF-10A mammary epithelial cells with paclitaxel in the presence and absence of the inhibitors iso-PPADS and A438079 did not result in a significant increase in extracellular ATP or a decrease in cell viability. These results indicate that P2RX7 is necessary for ATP release in TNBC cell lines exposed to chemotherapy. Furthermore, when TNBC cell lines were treated with increasing concentrations of ATP, there was a dose-dependent decrease in cell viability. Overall, these findings suggest that extracellular ATP may impact the chemotherapeutic response in TNBC cell lines through the activation of the ATP-gated channel P2RX7. Citation Format: Jasmine Manouchehri, Jharna Datta, Mathew Cherian. The role of purinergic signaling in the chemotherapy response of triple negative breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD15-08.

The ATP assay is more sensitive than the succinate dehydrogenase inhibition test for predicting cell viability

Aptamer-based strip assay is an easy, highly efficient and low-cost detection method, which has been developed and easily applied to onsite detection. A new sensitive sandwich dipstick assay for adenosine triphosphate (ATP) detection was successfully developed based on specific recognition between split aptamer fragments and the target. In this method, the thiolated aptamer was first conjugated to the surface of gold nanoparticles (AuNPs), while the biotin-aptamer was immobilized on the surface of a nitrocellulose filter in the test line. In the presence of ATP, the thiol-aptamer/ATP/biotin-aptamer complexes were generated, which led to an obvious increase in optical signals at the test line. Under the optimal determination conditions, an excellent linear logarithmic response to the ATP concentration was obtained within the range of 0.5μM to 5mM. The limit of detection (LOD) of 0.5μM was reached at a signal-to-noise ratio of 3. The dipstick assay showed a good average recovery of 96-108% with the RSD of less than 20% in urine samples. The proposed method exhibited high specificity against other nucleotides such as the uridine triphosphate (UTP), cytidine triphosphate (CTP), and guanosine triphosphate (GTP). The results indicated that the dipstick strip may be considered as an inexpensive screening tool for onsite ATP determination. Graphical Abstract A simple split aptamer fragments based sandwich-type dipstick assay was developed for ATP detection.

Visual inspections are used to assess hospital cleanliness, as visible contamination may present health risks and influence perceptions of care quality. Problematically, many contaminants are invisible to the naked eye, limiting the reliability of visual checks. Many invisible substances, however, fluoresce (i.e. emit visible light after absorbing electromagnetic radiation). Portable torches can detect fluorescent substances in situ, offering a potential method to enhance cleaning practices. This study has evaluated fluorescence as a tool for identifying general invisible contamination after hospital cleaning. Visibly clean surfaces in seven single-occupancy patient rooms and two six-bed wards across two National Health Service hospitals were examined using a portable high-intensity blue and ultraviolet light torch. Adenosine triphosphate (ATP) levels in fluorescent and non-fluorescent areas were taken as a recognized cleaning monitoring tool, and analysed statistically using Wilcoxon signed-rank tests. Fluorescent contamination that was invisible to the naked eye was found on every surface. ATP relative light unit (RLU) levels were significantly higher in fluorescent substances compared with non-fluorescent substances (P≤0.05) with large effect sizes on patient chairs, bed frames, overbed tables, bedside units and pillows, but not toilets, sinks or commodes. The mean RLU measurement was 161 in fluorescent areas compared with 33 RLU in control areas. Fluorescence detected alternative contamination which could present toxic risk to humans, such as cleaning fluid and/or drug-contaminated residue which frequently contain fluorescent constituents. This was an important finding as relying solely on ATP detection may overlook significant contamination risks. Further work to evaluate the method as a cleaning aid is encouraged.

Elevated tissue levels of zinc (Zn) have been associated with neurodegenerative diseases such as global ischemia, seizure, and Alzheimer's. The mechanism of action of Zn in causing neuronal injury is not clear. One of the possible mechanisms is the ability of Zn to alter cellular energy metabolism. Using the C6 glioma cell as a model, the present study aimed to determined the effects of increasing concentrations of Zn on cellular energy states, as defined by the levels of adenosine 5'-triphosphate (ATP), adenosine 5'-diphosphate (ADP), and adenosine 5'-monophosphate (AMP), the total adenosine nucleotides (TAN) (TAN = ATP + ADP + AMP), and the energy charge potential (ECP = [ATP + 0.5 ADP]/TAN). Uptake of Zn was visualized by the appearance of N-(6-methoxy-8-quinolyl)-p-toluene sulfonamide (TSQ)-stained fluorescent granules after a 3-h exposure to Zn in the medium. At [Zn] = 1 mM, cells appeared apoptotic. Levels of ATP and TAN decreased as the level of Zn increased. The change mirrors the increase in cell death as determined by the trypan blue exclusion test. However, when the ratio of ATP:ADP:AMP within the TAN was calculated, the percentage of ATP in the TAN increased significantly, while that of AMP decreased. The change in the relative AMP level mirrored the change in cell viability as measured by the MTT assay, which indicated a decreased in mitochondrial activity. Cellular ECP increased significantly from 0.85 ± 0.007 to 0.92 ± 0.04. The elevated ECP and relative ATP level, together with a significant decrease in the relative AMP level, are all indicators of inhibition of cellular metabolism. These results support the notion that acute exposure of C6 glioma cells to a high concentration of Zn might initially result in a decrease in relative AMP and an inhibition of mitochondrial activity. However, the ultimate toxic action of Zn on the C6 glioma cells appears to be due to a gradual inhibition of energy utilization, leading to cell shrinkage and apoptosis.