α-Ketoglutarate was identified by comparison with an authentic reference standard based on retention time and characteristic MRM transition (m/z 145.1 - 101.0). Quantification was further verified using the stable isotope-labeled internal standard (13C5-α-ketoglutaric acid). Calibration was performed using authentic α-ketoglutarate standards to ensure accurate metabolite identification and quantification.
"],"repository":["MetaboLights"],"study_status":["Public"],"ptm_modification":[""],"instrument_platform":["Liquid Chromatography MS - negative - reverse-phase"],"chromatography_protocol":["Chromatographic separation was performed using a liquid chromatography system coupled to a QTRAP 5500 mass spectrometer (AB Sciex, Framingham, MA, USA). Samples were separated on a T3 reversed-phase analytical column under optimized chromatographic conditions suitable for targeted α-KG quantification.
"],"publication":["LC-MS/MS Quantification of Nuclear α-KG in NSCLC."],"submitter_name":["Jiawen Cui"],"submitter_affiliation":["China Phramaceutical University"],"organism_part":["endometabolome"],"technology_type":["mass spectrometry assay"],"disease":[""],"extraction_protocol":["To quench metabolism and preserve intracellular α-ketoglutarate (α-KG), isolated nuclear pellets were extracted with 500 μL of pre-chilled 80% (v/v) methanol and incubated at −80°C for 2 h. Samples were centrifuged at 15,000 × g for 15 min at 4°C, and the supernatant containing extracted metabolites was collected and vacuum-dried. Prior to LC-MS/MS analysis, dried extracts were reconstituted in an appropriate solvent. Stable isotope-labeled 13C5-α-ketoglutaric acid was used as the internal standard.
"],"organism":["Homo sapiens"],"full_dataset_link":["https://www.ebi.ac.uk/metabolights/MTBLS15115"],"author":["Jiawen Cui. China Phramaceutical University. cuijw0514@outlook.com.","Jiali Liu. China Pharmaceutical University. TongJiaXiang #24, Nanjing, Jiangsu, China. carrie_CPU@hotmail.com."],"data_transformation_protocol":["Raw LC-MS/MS data were processed using the manufacturer’s software to integrate chromatographic peak areas. Quantification was performed by comparing analyte-to-internal-standard peak area ratios with an external calibration curve generated using authentic α-ketoglutarate standards. Nuclear α-KG concentrations were subsequently calculated by normalizing the quantified α-KG amount to the estimated total nuclear volume, assuming an average nuclear volume of approximately 1 pL per cell.
"],"study_factor":["Treatment"],"submitter_email":["cuijw0514@outlook.com"],"sample_collection_protocol":["Cultured cells were rapidly harvested on ice and washed with ice-cold phosphate-buffered saline (PBS). Nuclei were isolated immediately using a chilled sucrose-based fractionation protocol to minimize metabolic alterations. Cells were homogenized in ice-cold 0.25 M sucrose buffer (10 mM Tris-HCl, 3 mM MgCl2, pH 7.4), filtered, and layered onto a 0.34 M sucrose cushion. Following centrifugation at 700 × g for 10 min at 4°C, the nuclear pellet was collected and washed twice with 0.25 M sucrose buffer at 1,000 × g for 10 min. The purified nuclear pellet was immediately subjected to metabolite extraction.
"],"omics_type":["Metabolomics"],"study_design":["Metabolomics","Shimadzu SIL-20AC","QTRAP 5500","targeted analysis","cell culture","Homo sapiens","targeted metabolite profiling","non-small cell lung carcinoma","endometabolome","experimental sample"],"curator_keywords":["Metabolomics","Shimadzu SIL-20AC","QTRAP 5500","targeted analysis","cell culture","Homo sapiens","targeted metabolite profiling","non-small cell lung carcinoma","endometabolome","experimental sample"],"mass_spectrometry_protocol":["Mass spectrometric analysis was performed on a QTRAP 5500 triple quadrupole mass spectrometer equipped with an electrospray ionization (ESI) source operating in negative ion mode. Quantification was performed using multiple reaction monitoring (MRM). The MRM transition for α-ketoglutarate was m/z 145.1 - 101.0 with a declustering potential (DP) of −20 V and collision energy (CE) of −12 V. The isotopically labeled internal standard (13C5-α-ketoglutaric acid) was monitored using the transition m/z 151.06 - 105.0 with DP = −50 V and CE = −12 V. Instrument control and data acquisition were performed using the manufacturer’s software.
"],"additional_accession":[]},"is_claimable":false,"name":"LC-MS/MS Quantification of Nuclear α-KG in NSCLC","description":"This study contains targeted LC-MS/MS quantification of α-ketoglutarate (α-KG) in NSCLC cells using 13C-labeled α-KG internal standard. Nuclear α-KG levels were measured in A549, A549/DTX, PC9, and PC9/OR cells. In addition, nuclear α-KG was quantified in GLUD1-overexpressing A549 cells and GLUD1-knockdown A549/DTX cells. Mitochondrial α-KG measurements were performed exclusively in A549/DTX cells. The dataset includes raw SCIEX LC-MS/MS data, sample metadata, and processed quantitative results.","dates":{"publication":"2026-07-21","submission":"2026-07-21"},"accession":"MTBLS15115","cross_references":{}}