Sodium Formate Research Articles

141 Dietary Supplementation of Blends of Organic Acids and Monoglycerides Alleviated Diarrhea and Systemic Inflammation of Weaned Pigs Experimentally Infected with Enterotoxigenic Escherichia Coli F18

Abstract The objective of this experiment was to investigate dietary supplementation of organic acids blend, monoglycerides blend, and combination of both on growth performance, diarrhea, and systemic inflammation of weaned pigs experimentally infected with a pathogenic Escherichia coli (E. coli) F18. Forty pigs (7.81 ± 0.84 kg BW) were individually housed in disease containment rooms and randomly allotted to one of four treatments with 10 replicate pigs per treatment. The four dietary treatments were: 1) Control: nursery basal diet, 2) Acids: basal diet supplemented with a blend of organic acids (formic acid, lactic acid, and sodium formate) at 0.3%, 3) Monoglycerides: basal diet supplemented with a blend of monoglycerides of fatty acids at 0.3%, and 4) Combination of acids and monoglycerides: basal diet added with the acids blend at 0.2% and the monoglycerides blend at 0.2%. The experiment lasted 28 d [7 d before and 21 d after the first inoculation (d 0)]. All pigs were orally inoculated with E. coli F18 1010 CFU/3 mL for 3 consecutive days from d 0. Growth performance was measured weekly. Diarrhea score (1, normal, to 5, watery diarrhea) was daily recorded for each pig. Fecal samples were collected on d 2, 5, 7, 10, 14, and 21 post-inoculation (PI) to confirm the presence of β-hemolytic coliforms in feces. Whole blood samples were collected on d 0, 5, and 14 PI to perform complete blood counting analysis. All data were analyzed by ANOVA using the PROC MIXED of SAS with a pig as the experimental unit. Frequency of diarrhea was calculated and analyzed by Chi-square test. Supplementation of acids blend, monoglycerides blend, or the combination of both had limited impacts on growth performance throughout the trial but significantly reduced (P < 0.05) frequency of diarrhea (25.5 to 29.8%) compared with control (39.3%). E. coli F18 infection increased (P < 0.05) the counts of total white blood cells, neutrophils, and lymphocytes on d 5 and 14 PI, compared with d 0. Supplementation of the combination of acids and monoglycerides reduced (P < 0.05) the counts of total white blood cells, lymphocytes, and the ratio of neutrophils to lymphocytes, and tended (P < 0.10) to reduce neutrophil count on d 5 PI, compared with control. Pigs fed with 0.3% monoglycerides blend had greater (P < 0.05) neutrophil count than pigs in the control group on d 14 PI. In conclusion, dietary supplementation of organic acids blend, monoglycerides blend, and the combination of both can alleviate diarrhea or systemic inflammation caused by E. coli F18 infection.

High CO2 adsorption of ultra-small Zr-MOF nanocrystals synthesized by modulation method boosts the CO2/CH4 separation performance of mixed-matrix membranes

The separation performance of mixed matrix membranes (MMMs) is greatly impacted by both the inherent structure of porous fillers and the interfacial compatibility between the filler and matrix. Here, ultra-small Zr-MOFs (UiO-66-mod and NH2-UiO-66-mod) with more defect sites were synthesized through a simple sodium formate modulation strategy. Then, these modulated Zr-MOFs were used as porous fillers in combination with polyetherimide (PEI) to construct a high-quality mixed matrix membrane for efficient CO2 separation. The modulated Zr-MOF not only exposed more defect sites, which significantly enhanced the CO2 adsorption capacity but also exhibited high dispersion in the PEI matrix due to strong interfacial forces, avoiding non-selective voids. The 10-UiO-66-mod-PEI and 10-NH2-UiO-66-mod-PEI membranes developed here showed admirable CO2/CH4 separation performance (CO2 permeability of around 400 and 440 Barrer, CO2/CH4 selectivity of ∼33 and ∼47, respectively) much higher than that of non-modulated UiO-66-PEI membranes, surpassing the 2008 upper bound of MMMs. This work demonstrated that the proposed UiO-66-mod-PEI and NH2-UiO-66-mod-PEI MMMs could be potential candidates for an efficient CO2 capture process.

Safe cycling in winter: Results of a case study on the role of de-icing in the city of Hamburg, Germany

Introduction: In parts of Europe and North America, cycling volumes decrease in winter due to a reduction in subjective safety. To counter this, high-quality winter maintenance is required on cycle paths. At the moment, grit and sodium chloride are considered state-of-the-art gritting/de-icing materials in Germany. However, grit has to be removed after winter because it poses a serious injury risk on dry streets, and, in various German cities, using sodium chloride is prohibited on segregated bike paths due to the harmful impact on surrounding trees. Therefore, there is a need for alternative gritting/de-icing materials. Method: We used a mixed-methods approach consisting of qualitative and quantitative surveys together with laboratory investigations and a life cycle assessment to find suitable alternatives to sodium chloride and grit for use on segregated bike paths, and tested four de-icing materials (sodium chloride as a reference, sodium formate, calcium magnesium acetate or CMA, and potassium acetate) at two sites in Hamburg, Germany. The tests were accompanied by on-site cyclist surveys. Results: The results show that the use of alternative (non-sodium chloride) de-icing materials either reduces or eliminates negative impacts on the environment at a local level, for example on trees along the cycle path. However, this reduction goes hand in hand with increasing negative environmental impacts at a global level due to higher overall emissions associated with the tested alternative de-icing materials. Regarding cyclists’ safety, sodium formate was the only de-icing material which delivered comparable results to sodium chloride and should therefore be tested in extended conditions. Conclusions: Further research is needed on the large-scale application of the investigated de-icing agents on cycle paths in different cities, along with a survey of a larger number of cyclists. A final evaluation of the environmental aspects can only be made when the supply and production conditions for large-scale use are clear. Practical Applications: Basically there are two options for the practical application of de-icing materials: The usage of the costlier alternatives with better properties at a local level in the hope of fast development towards a better global GHG footprint in their manufacturing processes, or sticking to the use of grit and sodium chloride (where it is possible) while committing to improving clean-up after the snow and ice melt to prevent unsafe road conditions in spring.

Development of a Simple Electroless Method for Depositing Metallic Pt-Pd Nanoparticles over Wire Gauge Support for Removal of Hydrogen in a Nuclear Reactor.

Electroless noble metal deposition on the conducting substrate is widely used to obtain the desired film or coating on the substrate of interest. Wire-gauge-based Pt/Pd/Pt-Pd (individually, sequentially, and simultaneously deposited) catalysts have been developed using formaldehyde and sodium formate as reducing agents. Various surface pretreatment methods like SnCl2 + PdCl2 seeding, oxalic acid etching, and HCl activation (etching) have been employed to obtain the desired noble metal coating. Minimum time duration was observed for simultaneously deposited catalysts using formaldehyde as a reducing agent. Prepared catalysts were characterized for noble metal deposition, coating kinetics, surface morphology, and binding energy. The catalyst was found to be active for H2 and O2 recombination reactions for hydrogen mitigation applications in nuclear reactors.

Myricetin causes site-specific DNA damage via reactive oxygen species generation by redox interactions with copper ions.

Myricetin (MYR), found in tea and berries, may have preventive effects on diseases, including Alzheimer's disease and cancer. However, MYR is also a mutagen, inducing DNA damage in the presence of metal ions. We have studied the molecular mechanisms of DNA damage by MYR in the presence of Cu(II) (MYR+Cu). Using 32P-5'-end-labeled DNA fragments, we analyzed site-specific DNA damage caused by MYR+Cu. MYR+Cu caused concentration-dependent DNA strand breaks and base alterations, leading to cleavage of DNA at thymine, cytosine, and guanine nucleotides. Formation of the oxidative DNA damage indicator, 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), in calf thymus DNA was increased by MYR+Cu. The production of 8-oxodG in MYR-treated HL-60 cells was significantly higher than in HP100 cells, which are more resistant to H2O2 than are HL-60 cells. Reactive oxygen species (ROS) scavengers were used to elucidate the mechanism of DNA damage. DNA damage was not inhibited by typical free hydroxyl radical (•OH) scavengers such as ethanol, mannitol, or sodium formate. However, methional, catalase, and bathocuproine inhibited DNA damage induced by MYR+Cu. These results suggest that H2O2, Cu(I), and ROS other than •OH are involved in MYR+Cu-induced DNA damage. We conclude that the Cu(I)/Cu(II) redox cycle and concomitant H2O2 production via autoxidation of MYR generate a complex of H2O2 and Cu(I), probably Cu(I)-hydroperoxide, which induces oxidative DNA damage.

Experimental study of solution defrosting characteristics of air source heat pump

Air source heat pumps are widely used due to their high efficiency, energy-saving, and environmentally friendly nature. However, frost accumulation on heat exchanger surfaces restricts their application in regions with low temperatures and high humidity. Additionally, existing defrosting methods have certain limitations. To address these issues, this study presents a defrosting solution rooted in the chemical potential theory. The defrosting mechanism is first scrutinized through this theory. Subsequently, a system for air source heat pump solution defrosting is devised, along with a simulation test setup to explore defrosting characteristics utilizing sodium formate (HCOONa) solution. Outcomes reveal the efficacy of sodium formate in eliminating exchanger frost. Sustaining air circulation during defrosting could expedite frost layer removal and shorten the defrosting duration. Moreover, greater spray flow rate, temperature, and defrosting solution concentration correlate with reduced defrosting time. Notably, in this experiment, the defrosting amounts for the two experimental conditions were essentially the same at the time points of 90 s, 180 s, and 270 s at solution concentrations of 25% and 30%. This indicates that further increasing the solution concentration does not significantly accelerate the rate of frost melting.

Visible Light‐Driven, Persulfate‐Mediated Hydrocarboxylation of Vinylsulfones

AbstractWe report a visible light‐mediated approach for the radical hydrocarboxylation of vinylsulfone derivatives. Using cheap and easily accessible sodium formate as C1‐source and K2S2O8 as reagent, a set of vinylsulfone substrates could be efficiently hydrocarboxylated in aqueous medium without any additional catalyst or reagent; and the concept could be also applied for direct hydroacylations, hydroalkylations and hydrophosphorylations. The control experiments clearly indicated that the reaction proceeds via radical mechanism without the generation of electron donor‐acceptor (EDA) complexes; supporting the working model of K2S2O8‐initiated in situ formation of CO2 radical anion.

Chemical diversity of dissolved organic matter revealed by ultra performance liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry

Dissolved organic matter (DOM) is a highly complex and heterogeneous mixture that exists in various environments, including rivers, oceans, soils, and atmospheric aerosols. DOM plays a crucial role in biogeochemical cycles and significantly influences the environment by regulating water quality, changing the climate, and transporting pollutants. Therefore, clarifying the detailed molecular composition of DOM is essential to obtain a better understanding of its physical and chemical properties, thereby enabling further elucidation of its biogeochemical behavior. In this study, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) combined with quadrupole detection (QPD) was used to conduct the online ultra performance liquid chromatography (UPLC)-MS analysis of DOM in water, aerosol, and soil samples collected in Tianjin, China. The samples were extracted with pure water and filtered through a glass fiber membrane (0.45 μm). The DOM in the samples was then enriched by solid-phase extraction (SPE) and redissolved in water-acetonitrile (1∶1, v/v) at mass concentration of 200 mg/L for the LC-MS experiments. The mobile phases used for UPLC were water containing 0.1% (v/v) formic acid (A) and acetonitrile containing 0.1% (v/v) formic acid (B). The gradient elution procedure was as follows: 0-5 min, 0B; 5-11 min, 0B-95%B; 11-25 min, 95%B; 25-28 min, 95%B-0B; 28-30 min, 0B. The flow rate was 0.1 mL/min, and the injection volume was 10 μL. The UV wavelength was set at 274 nm. MS detection was performed in negative electrospray ionization (ESI(-)) mode with a capillary voltage of 5.0 kV, and the MS data were collected in broadband (m/z 150-1000) and QPD modes. The transient data size was set to 2M, the free induction decay signal length was 0.74 s, and the ion accumulation time was 0.030 s. Four chromatographic peaks were observed in the chromatograms. The first peak was identified as salt adduct compounds containing sodium formate. The three other peaks contained complex components, such as oxygen-rich, unsaturated tannin-like compounds, as well as low-oxygen, highly saturated lignin-like and protein/amino-like compounds. UPLC-FT-ICR MS was suitable for assigning the detailed elemental compositions of the DOM samples. UPLC effectively improved the ionization efficiency of difficult-to-ionize compounds and enhanced the detection accuracy of MS. Indeed, MS peaks with a mass difference of as small as 3.4 mDa were well identified. A total of 12027, 15593, and 8029 peaks in the mass spectra of the water, aerosol, and soil samples, respectively, were assigned to known elemental formulae. Peaks Ⅱ and Ⅲ were hydrophilic components mainly including CHNO and CHO compounds. Compared with peak Ⅱ, peak Ⅲ exhibited a significant increase in CHNOS and CHOS, indicating that UPLC exerted a certain separation effect on these compounds. Furthermore, the aerosol samples contained a higher concentration of sulfur-containing compounds than the water and soil samples, primarily because of the abundance of organic sulfates present in atmospheric and cloud water. Data processing and graphic visualization revealed that the unique components in the water samples mainly appeared in the area of 0.1<O/C<0.5 and 1.0 <H/C<1.7. The compounds detected were low-oxygen and highly condensed lignin-like compounds. The unique components in the aerosol samples appeared in the area of 0.4<O/C<1.0 and 1.5<H/C<2.0, and were classified as carbohydrates. The unique components in the hydrophilic fraction of the soil samples were found in the area of 0.6<O/C<1.0 and 0.5<H/C<1.0, and were determined to be tannin-like compounds. By contrast, the components in the hydrophobic fraction were similar to those found in the water samples and appeared in the region containing lignin-like compounds. In summary, this study proposed a novel analytical protocol to characterize DOM from different ecosystems using UPLC-FT-ICR MS. This method could separate DOM components using UPLC with eluents of different polarities and analyze them using high-resolution FT-ICR MS to reveal their molecular compositions and possible chemical types. This protocol offers solid technical support for the comprehensive profiling of DOM at the molecular level.

Phase Equilibria in the Sodium Formate–Glycerol–Water System at Temperatures Below 0°С

Phase Equilibria in the Sodium Formate–Glycerol–Water System at Temperatures Below 0°С

PdIr nanoparticles on NH2-functionalized dendritic mesoporous silica nanospheres for efficient dehydrogenation of formic acid

Developing highly efficient solid catalysts for formic acid (HCOOH, FA) dehydrogenation is essential to utilize FA as a hydrogen (H2) carrier. In this work, ultrafine bimetallic PdIr nanoparticles (NPs) supported on the amine-functionalized dendritic mesoporous silica nanospheres (PdIr/DMSNs-NH2) have been successfully synthesized by the simple surface functionalization and co-reduction method. The optimized Pd4Ir1/DMSNs-NH2 (Pd/Ir molar ratio = 4:1) catalyst displayed the remarkable catalytic performance with 100 % H2 selectivity of the FA dehydrogenation, and the initial turnover frequency (TOF) could achieve 1333 h−1 with the additive of sodium formate (SF) at 298 K, which is comparable to the most effective mesoporous silica supported Pd-containing solid catalysts. The activation energy (Ea) for the FA dehydrogenation of Pd4Ir1/DMSNs-NH2 catalyst in the FA-SF mixture is 39.7 KJ/mol, lower than most reported catalysts. Furthermore, the optimized catalyst maintained 100 % H2 selectivity even after five runs, only with a negligible decrease in the activity, displaying the excellent stability of the catalyst. The superior catalytic performance could be attributed to the synergistic effect of open dendritic pore channel, high dispersion and ultrafine size of PdIr NPs as the active sites on DMSNs-NH2, and regulated electronic effects of Pd and Ir. More importantly, introducing –NH2 groups to the DMSNs could facilitate the O–H bond dissociation of FA and improve the FA dehydrogenation activity under mild conditions. This work will significantly promote FA as a hydrogen carrier on fuel cells.

One‐pot Upcycling of Waste Plastics for Selective Hydrogen Production at Low‐Temperature

AbstractTowards global efforts for efficient and sustainable ways to utilize polyethylene terephthalate (PET)‐based plastic waste, herein we report an integrated process for the complete one‐pot transformation of PET‐based plastic waste for hydrogen gas production in an alkaline aqueous condition over a heterogeneous ruthenium catalyst at low temperature (110‐160 °C). We could achieve complete selectivity with a high yield of H2 gas (∼38,000 mL H2/gPET/gRu) without any traces of CO and CO2 contaminations. Complete depolymerization of different types of PET‐based plastic waste was also achieved with high carbon yield (∼98 %) for disodium terephthalate (Na2TPA, 5.2 mmol/gPET) and sodium formate (SF, 9.6 mmol/gPET), along with H2 gas. Moreover, the developed process is scalable to bulk‐level production of hydrogen gas from PET‐based plastic waste, highlighting the potential application of the developed process.

Synthetic polymer fracturing fluid weighted by sodium formate enables fracture stimulations in Ultra-High pressure and High-Temperature reservoir

Weighted fracturing fluid was considered to be one of the key technologies to deal with the challenge of abnormally high pressure and ultra-high temperature reservoir stimulation in the case of existing fracturing equipment. In this work, a thickener polymer Pt-Fb that meets the requirements of fracturing fluid weighting by HCOONa was synthesized. And HCOONa- weighted fracturing fluid with delayed crosslinking characteristics and good friction reduction performance was developed based on the polymer Pt-Fb. It is much cheaper than CHKO2-weighted guar gum fracturing fluid. The density of HCOONa-weighted fracturing fluid was up to 1.3 g/cm3. The fracturing fluid proposed in this study meets the temperature resistance and shear resistance requirements of 170 °C and 170 s−1. Besides, a complete gel breaking was obtained by using NaBrO3, and the internal mechanism was investigated from both experimental and theoretical aspects. It was revealed that a mild multi-step oxidation reaction enables NaBrO3 to break the HCOONa-weighted fracturing fluid.

Efficient enrichment of platinum group metals from spent automotive catalysts by alkaline hydrothermal treatment and the subsequent acid leaching method

Spent automotive catalysts (SAC) is the most important secondary resource for the recovery of platinum group metals (PGMs). This paper demonstrates that the acid-resistant and alkali-resistant cordierite carrier can be transformed into hydroxysodalite by a alkaline hydrothermal treatment (AHT), which can then be dissolved by subsequent acid leaching (AL) to enrich PGMs. Experiments were conducted to assess the influencing factors and the optimal conditions were determined as follows: holding temperature of 150 °C; NaOH to raw material mass ratio 10:10; holding time of 60 min; liquid to solid ratio of 3:1, and stirring speed of 400 rpm. The residue ratio in the AHT process was 132.57% under optimized conditions. The total residue ratio was 18.68% under fixed acid leaching experimental conditions of holding temperature of 60 °C, liquid to solid ratio of 15:1, holding time of 60 min, stirring speed of 400 rpm, and hydrochloric acid concentration of 2.5 mol·L-1. The contents of Pt, Pd, and Rh in the enriched residue reached 650.50, 2131.54, and 405.28 g·t−1, respectively, and the corresponding enrichment times were 7.13, 7.25, and 7.07. The additions of sodium formate before the AHT and aluminum powder during the AL were found to effectively inhibit PGMs leaching. The losses of Pt, Pd, and Rh throughout the entire process were only 2.77%, 1.89%, and 4.28%, respectively.

Electrochemical reduction of formic acid to diamond-like carbon films on stainless steel in aqueous solutions

Diamond-like carbon (DLC) films show attractive applications in surface modification of stainless steels (SS) owing to their high corrosion resistance and low friction coefficient. Electrodeposition is a cost-efficient method to prepare carbon films. DLC films were electrodeposited from formic acid solutions, however severe hydrogen evolution on stainless steel led to extremely low current efficiencies. Sodium formate was used to reduce the concentration of protons in the electrolyte and slightly improved the current efficiency. To further inhibit hydrogen evolution, dimethyl sulfoxide was added into the electrolyte as a proton acceptor. The current efficiency for carbon deposition increased more than 28 times, and the deposition rate reached as high as 1.6 μm h−1. The corrosion and wear resistance of DLC coated stainless steel were improved.

Photochemical Hydride Generation in Sulfite Medium: Sample Introduction into an Inductively Coupled Plasma Mass Spectrometer for the Determination of Ultratrace Inorganic Arsenic.

This Technical Note reports a new UV photochemical hydride generation (PHG) of As(III/V) in a sulfite medium. Combining PHG for sample introduction with sector field inductively coupled plasma mass spectrometry (SF-ICPMS) for detection, we established a novel and ultrasensitive approach for the determination of total inorganic As. Arsine was generated simply by exposing arsenic solutions containing 2 mM of sodium sulfite to UV irradiation for 10 s with 1 mM of sodium formate for sensitivity enhancement. An impressive limit of detection of 0.2 ng/L for As, suitable for the quantitation of inorganic arsenic at ultratrace levels, was readily achieved. Formation of hydrated electrons and hydrogen radicals was experimentally validated, and this may be responsible for the reduction of the high-valent arsenic species. The PHG may also provide a new and useful alternative to conventional hydride generation and photochemical vapor generation for the determination of other trace elements, such as Se(VI) and Te(VI), and by other atomic spectrometric techniques.

Precipitation of Pt, Pd, Rh, and Ru Nanoparticles with Non-Precious Metals from Model and Real Multicomponent Solutions.

This article presents studies on the precipitation of Pt, Pd, Rh, and Ru nanoparticles (NPs) from model and real multicomponent solutions using sodium borohydride, ascorbic acid, sodium formate, and formic acid as reducing agents and polyvinylpyrrolidone as a stabilizing agent. As was expected, apart from PGMs, non-precious metals were coprecipitated. The influence of the addition of non-precious metal ions into the feed solution on the precipitation yield and catalytic properties of the obtained precipitates was studied. A strong reducing agent, NaBH4 precipitates Pt, Pd, Rh, Fe and Cu NPs in most cases with an efficiency greater than 80% from three- and four-component model solutions. The morphology of the PGMs nanoparticles was analyzed via SEM-EDS and TEM. The size of a single nanoparticle of each precipitated metal was not larger than 5 nm. The catalytic properties of the obtained nanomaterials were confirmed via the reaction of the reduction of 4-nitrophenol (NPh) to 4-aminophenol (NAf). Nanocatalysts containing Pt/Pd/Fe NPs obtained from a real solution (produced as a result of the leaching of spent automotive catalysts) showed high catalytic activity (86% NPh conversion after 30 min of reaction at pH 11 with 3 mg of the nanocatalyst).

Sodium formate market size, share will grow at 5.1% CAGR to reach over $674 M by 2030 in global chemical industry sector

Sodium formate market size, share will grow at 5.1% CAGR to reach over $674 M by 2030 in global chemical industry sector

Visible-Light/Nickel-Catalyzed Carboxylation of C(sp2) Bromides via Formate Activation.

A new visible-light-driven method for the carboxylation of (hetero)aryl/vinyl bromides has been developed using catalytic 4CzIPN, nickel, phenyl triflimide, and sodium formate as a carboxylation agent. Interestingly, we found catalytic phenyl triflimide plays an essential role in promoting the reaction. While many C(sp2) carboxylation reactions require harsh reagents or gaseous carbon dioxide, we demonstrate the mild and facile construction of carboxylic acids from readily available starting materials.

Ion-exchange resin-supported palladium catalysts for hydrodehalogenation of aryl halides under batch and continuous flow conditions

Anion-exchange resin-supported palladium catalysts for dehalogenation of aromatic halides have been prepared by immobilizing Pd(II) on anion-exchange resins followed by reduction in hydrogen atmosphere. These catalysts showed high catalytic activity and selectivity in the hydrodehalogenation of various aryl halides both by hydrogen transfer from aqueous sodium formate in water–ionic liquid mixtures under batch conditions, and by hydrogenation in ethanol under moderate pressure of H2 in a continuous flow microreactor.

Intensity-dependent mass search for improving metabolite database matches in chemical isotope labeling LC-QTOF-MS-based metabolomics

Liquid chromatography mass spectrometry (LC-MS) has been increasingly used for metabolome analysis. One of the critical steps in the LC-MS metabolome analysis workflow is related to metabolite identification. Among the measured parameters, peak mass is commonly used to search against a database for potential metabolite matches. Higher accuracy mass measurement allows the use of a narrower mass tolerance window for mass search. While various types of mass analyzers can routinely measure a peak mass with an error of less than a few ppm, mass measurement accuracy is not uniform for peaks with different intensities, particularly for quadrupole time-of-flight (QTOF) MS. Herein we present a simple and convenient method to determine the relation between peak intensity and mass error in LC-QTOF-MS-based metabolome analysis, followed by intensity-dependent mass search (IDMS) of a database for metabolite matches. This method is based on running a series of sodium formate mass calibrants, as part of the standard operating procedure (SOP) in LC-MS data acquisition, and then curve-fitting the measured mass errors and peak intensities. We show that, in two different quadrupole time-of-flight (QTOF) mass analyzers, mass accuracy is generally reduced as peak intensity decreases, which is independent of m/z values in the range commonly used for metabolite detection (e.g., m/z < 1000). We demonstrate the improvement in metabolite matches using IDMS in the analyses of dansyl labeled standards and human urine samples. We have implemented the IDMS method in the freely available MCID database at www.mycompoundid.org, which is composed of 8021 known human endogenous metabolites and their predicted metabolic products (375,809 compounds from one metabolic reaction and 10,583,901 compounds from two reactions).