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Trifluoroacetic AcidFluoroacetatesAcetic AnhydridesChromatography, High Pressure LiquidHydrochloric AcidChromatography, Reverse-PhaseSpectrometry, Mass, Electrospray IonizationSpectrophotometry, UltravioletMolecular StructureMass SpectrometrySolventsCyanogen BromideIndicators and ReagentsChromatography, LiquidPeptidesAmino AcidsChromophore-Assisted Light InactivationSpectrometry, Mass, Matrix-Assisted Laser Desorption-IonizationPeptide FragmentsAmino Acid Sequence

AnhydrideAceticTrifluoromethanesulfonicHydrolysisHPLCAmino acidMethyl EsterMass spectrometryConcentrationDifluoroaceticChromatographyPeptideCompoundsCommonlySaltReagentSynthesisDerivativesLipidChemicalsChemicalWaterCharacteristicsSulfuricProtocolDetectionOrganicStabilityStrengthSizeCellApproximately

Anhydride2

• TFA is prepared industrially by the electrofluorination of acetyl chloride or acetic anhydride, followed by hydrolysis of the resulting trifluoroacetyl fluoride: CH 3COCl + 4 HF → CF 3COF + 3 H 2 + HCl CF 3COF + H 2O → CF 3COOH + HF Where desired, this compound may be dried by addition of trifluoroacetic anhydride. (wikipedia.org)
• TFA is the precursor to many other fluorinated compounds such as trifluoroacetic anhydride, trifluoroperacetic acid, and 2,2,2-trifluoroethanol. (wikipedia.org)

Acetic4

• It is a structural analogue of acetic acid with all three of the acetyl group's hydrogen atoms replaced by fluorine atoms and is a colorless liquid with a vinegar-like odor. (wikipedia.org)
• TFA is a stronger acid than acetic acid, having an acid ionisation constant, Ka, that is approximately 34,000 times higher, as the highly electronegative fluorine atoms and consequent electron-withdrawing nature of the trifluoromethyl group weakens the oxygen-hydrogen bond (allowing for greater acidity) and stabilises the anionic conjugate base. (wikipedia.org)
• In this paper, we have systematically studied the influence of trifluoroacetic acid, acetic acid and their salts on the synthesis of helical mesoporous materials in the presence of a cationic surfactant cetyltrimethylammonium bromide (CTAB) as a template. (edu.au)
• For example, acetic acid has a specific gravity (sg) of 1.0491 while acetone has a sg of 0.785 ( 784.58 kg/cu.m) - see table below. (simetric.co.uk)

Trifluoromethanesulfonic2

• Testing also detected trifluoroacetic acid (TFA) and trifluoromethanesulfonic acid (TFMS). (healthday.com)
• Trifluoroacetic or trifluoromethanesulfonic acids may also be adequate substitutes. (ilpi.com)

Hydrolysis3

• The methods used were Driselase digestion and trifluoroacetic acid (TFA) hydrolysis. (bl.uk)
• This can be achieved by acid hydrolysis, typically using hydrochloric acid (HCl) or trifluoroacetic acid (TFA). (pharmiweb.com)
• The hydrolysis process breaks the peptide bonds, converting proteins into their constituent amino acids. (pharmiweb.com)

HPLC3

• HPLC can detect and quantify amino acids in trace amounts. (pharmiweb.com)
• IEC, HPLC or CE) and detection methods described above to identify and quantify amino acids in protein samples. (pharmiweb.com)
• Combining mass spectrometry with separation techniques such as HPLC or CE can improve the accuracy and sensitivity of amino acid analysis. (pharmiweb.com)

Amino acid8

• SDR enzymes have critical roles in lipid, amino acid, carbohydrate, cofactor, hormone and xenobiotic metabolism as well as in redox sensor mechanisms. (researchgate.net)
• Protein amino acid analysis is a technique for determining the type and amounts of amino acids in a protein sample, providing information on protein composition, post-translational modifications and overall protein quality. (pharmiweb.com)
• By gaining insight into amino acid content, researchers can assess protein purity, determine changes in amino acid composition, and evaluate protein stability. (pharmiweb.com)
• What is Protein Amino Acid Analysis? (pharmiweb.com)
• Automated instruments specifically designed for protein amino acid analysis. (pharmiweb.com)
• A reversed-phase column is commonly used for amino acid analysis. (pharmiweb.com)
• The 131 I radiolabel generally clears rapidly from the tumor after internalization and subsequent degradation of the bivalent l -amino acid peptide ( l -a.a. peptide) in the tumor cells. (snmjournals.org)
• We have developed an effective pretargeting system based on a biologically produced bs-mAb (antirenal cell carcinoma [RCC] x anti-DTPA(In) bs-mAb: G250xDTIn-1) and an 111 In-labeled bivalent l -amino acid peptide ( l -a.a. peptide) (Ac-Phe-Lys(DTPA)-Tyr-Lys(DTPA)-NH 2 ) (DTPA is diethylenetriaminepentaacetic acid) ( 10 ). (snmjournals.org)

Methyl Ester1

• The analysis involves extraction of TFA by sulfuric acid and methanol followed by derivatization to the methyl ester of TFA (MTFA). (elsevierpure.com)

Mass spectrometry2

• Trifluoroacetic acid is commonly used as a mobile phase additive in liquid chromatography-mass spectrometry (LC-MS). (sigmaaldrich.com)
• Trifluoroacetic acid may be used as a mobile phase additive for the analysis of basic compounds in biological samples using hydrophilic interaction liquid chromatography-electrospray ionization coupled to tandem mass spectrometry (HILIC-ESI/MS/MS) and reversed-phase liquid chromatography coupled to tandem mass spectrometry (RP-LC-MS/MS). (sigmaaldrich.com)

Concentration3

• A simple and sensitive analytical procedure was developed to determine the concentration of trifluoroacetic acid (TFA) in plant, soil, and water samples. (elsevierpure.com)
• The amino acids are eluted in a specific order and their concentration can be determined by various detection methods. (pharmiweb.com)
• Can detect specific amino acids based on unique absorbance spectra, thus providing valuable information about the concentration of amino acids in protein samples. (pharmiweb.com)

Difluoroacetic1

• Fluoroacetic acid - highly toxic but naturally occurring rodenticide CH2FCOOH Difluoroacetic acid Trichloroacetic acid, the chlorinated analog Kreglewski, A. (1962). (wikipedia.org)

Chromatography2

• Amino acids are first converted into volatile derivatives, which are then separated and detected by gas chromatography. (pharmiweb.com)
• After derivatization, the amino acids are separated using liquid chromatography. (pharmiweb.com)

Peptide3

• One complication to its use is that TFA forms an azeotrope with water (b. p. 105 °C). TFA is popularly used as a strong acid to remove protecting groups such as Fmoc and BOC used in organic chemistry and peptide synthesis. (wikipedia.org)
• a ) Maximal fluorescence response to 10 μM glucagon-like peptide-1 (GLP-1) of the prototype GLP-1 sensor and the N-terminus deletion variants (16 or 23 first amino acids). (elifesciences.org)
• To improve the residence time of the iodine label in the tumor, a new bivalent peptide was synthesized that is peptidase resistant and consists of 4 d -amino acids ( d -a.a. peptide). (snmjournals.org)

Compounds2

• Following UV examination, the compounds were visualized by treatment with trifluoroacetic-acid or 25 percent sulfuric-acid. (cdc.gov)
• Trifluoroacetic-acid treatment did not reveal the presence of blue compounds with Rf values resembling any of the standards. (cdc.gov)

Commonly1

• The most commonly found PFAS was perfluorooctanoic acid (PFOA), which has been banned worldwide since 2020. (healthday.com)

Salt2

• Results show that helical mesostructures can be successfully synthesized when CF3COO- anions were used as additives with an additive/CATB molar ratio (R) range of 0.1-0.375 for the CF3COOH/CTAB templating system and a relatively wider R range of 0.1-0.5 for the CF3COONa/CTAB templating system, which can be attributed to the influence of pH caused by the acid- or salt-form of additives. (edu.au)
• As an acid or as a salt TFA is low to moderately toxic to a range of organisms. (edu.au)

Reagent2

• It is a reagent used in organic synthesis because of a combination of convenient properties: volatility, solubility in organic solvents, and its strength as an acid. (wikipedia.org)
• Polyphenols found in the enzyme preparation were found to interfere with the reduction of the dinitrosalicylic acid reagent. (who.int)

Synthesis1

• The modular synthesis is based on Suzuki cross-coupling of the aryl substituents as boronic acid precursors with 5,8-dibromo-2-( tert -butyl)-4,9-dimethoxy-2,3-dihydro-1H-phenalen-1-one, and the subsequent transformation of the product to the desired 2,5-diaryl 6-hydroxyphenalenone in a reduction/deprotection sequence. (thieme-connect.com)

Derivatives1

• In the present study, we show that benzoic acid derivatives isolated from Bjerkandera adusta promote the activity of the two main protein degradation systems, namely the ubiquitin-proteasome (UPP) and especially the autophagy-lysosome pathway (ALP) in human foreskin fibroblasts. (mdpi.com)

Lipid1

• In the cell, RNF213 was shown to be involved in fatty acid metabolism ( 11 ), and to associate with intracellular lipid droplets in a manner dependent on its E3 ligase and ATPase activities ( 12 ). (biorxiv.org)

Chemicals1

• 1995). Diisocyanates and acid anhydrides cyanates has a low association with atopy, low prevalence are among the most common low molecular weight (LMW) with specific IgE antibodies and a mixed Th1-Th2 response classes of chemicals responsible for occupational asthma. (cdc.gov)

Chemical1

• Trifluoroacetic acid (TFA) is an organofluorine compound with the chemical formula CF3CO2H. (wikipedia.org)

Water1

• The mobile phase, typically a gradient of water and organic solvent, facilitates the elution of amino acids from the column. (pharmiweb.com)

Characteristics1

• IEC separates amino acids based on their charge characteristics using ion exchange resins. (pharmiweb.com)

Sulfuric1

• TFA is also less oxidizing than sulfuric acid but more readily available in anhydrous form than many other acids. (wikipedia.org)

Protocol1

• Trifluoroacetic acid (TFA) is a breakdown product of several hydrochlorofluorocarbons (HCFC), regulated under the Montreal Protocol (MP), and hydrofluorocarbons (HFC) used mainly as refrigerants. (edu.au)

Detection3

• Amino acids are generally not very amenable to direct detection by LC-MS due to their low ionization efficiency. (pharmiweb.com)
• The column separates the amino acids based on their hydrophobicity, allowing for their individual detection and quantification. (pharmiweb.com)
• Once separated by LC, the amino acids enter the mass spectrometer for detection and quantification. (pharmiweb.com)

Organic1

• I was wondering if anyone knows of any actual data about the stability of various perchloric acid-organic solvent mixtures. (ilpi.com)

Stability1

• I've had some problems in the past with other witch's brews used for electropolishing, after which I determined that the literature-reported composition was beyond the actual stability limit for the particular (ethanol-nitric acid) system, so that's kind of sensitized me to this application. (ilpi.com)

Strength1

• The investigator tells me that it's the acid strength that's really needed, not the oxidizing power. (ilpi.com)

Size1

• shatavari d1-trifluoroacetic acid is very confusing negramm and depends on the size of fines. (eventenergy.ru)

Cell1

• The effect of bs-mAb-diDTPA-bs-mAb (DTPA is diethylenetriaminepentaacetic acid) bridging at the tumor cell surface on the internalization of the bs-mAb-diDTPA complex was investigated in SK-RC-52 tumor-bearing mice. (snmjournals.org)

Approximately1

• 7.5%) of the approximately 0.2 µg acid equivalents/L estimated to be present at the start of the millennium. (edu.au)