{"PMD":0.98402,"origin":"OH ↔ NH2, e.g. de-amidiation, CHNO compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":1.99566,"origin":"F ↔ OH, halogen exchange with hydroxy group (typically -F + OH)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":2.01565,"origin":"± 2H, opening or forming of double bond","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":7.00467,"origin":"F ↔ CN, halogen exchange with cyano group","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":8.96578,"origin":"Cl ↔ CN, halogen exchange with cyano group","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":13.97927,"origin":"O ↔ 2H, e.g. Oxidation follwed by H2O elimination","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":14.01565,"origin":"± CH2, alkane chains, waxes, fatty acids, methylation,'-[C3H6ON] ↔ -[C2H4ON], acrylamide versus iodoacetamide in cysteine alkylation (","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2, https://doi.org/10.1073/pnas.92.11.5072","mode":"both"}
{"PMD":15.97716,"origin":"S ↔ O, sulfur compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":15.99492,"origin":"± O, e.g. oxidation/reduction","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":17.02655,"origin":"± NH3, ammonium adduct/neutral ammonium loss, NH4+↔ H+, salt adduct","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":17.96611,"origin":"Cl ↔ OH, halogen exchange with hydroxy group (typically -Cl + OH)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":17.99058,"origin":"F ↔ H, halogen exchange","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":18.01056,"origin":"± H2O, water addition/loss","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":18.99458,"origin":"CN ↔ COOH, nitrile compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":24.99525,"origin":"CN ↔ H, nitrile compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":27.0109,"origin":"± HCN, nitrile compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":27.99491,"origin":"± CO","Ref.":"Spektroskopische Methoden in der organischen Chemie, Georg Thieme Verlag, Stuttgart, 3. Aufl. 1987, ISBN: 3-13-576103-7","mode":"both"}
{"PMD":28.00615,"origin":"- 2N, nitrogen loss, e.g. azido compounds (N2)","Ref.":"Spektroskopische Methoden in der organischen Chemie, Georg Thieme Verlag, Stuttgart, 3. Aufl. 1987, ISBN: 3-13-576103-7","mode":"both"}
{"PMD":28.0313,"origin":"± C2H4, natural alkane chains such as fatty acids","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":29.97418,"origin":"NO2 ↔ NH2, nitro compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":29.99799,"origin":"-NO, nitroso compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":31.97207,"origin":"± S, sulfur compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":31.98983,"origin":"± 2O, oxygen loss","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":32.02622,"origin":"CH3OH, methanol clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":33.02146,"origin":"- NH2OH, loss from hydroxamic acids","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":33.96103,"origin":"Cl ↔ H, halogen exchange","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":33.98772,"origin":"± H2S, sulfur compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":37.98916,"origin":"2CN ↔ 2COOH, nitrile compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":40.0313,"origin":"+(C3H6O - H2O), acetone condensation after dehydration","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":41.02655,"origin":"CH3CN, acetonitrile clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":42.01056,"origin":"± COCH2","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":42.04695,"origin":"± C3H6, propylation","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":43.00581,"origin":"± CONH (wrong calc. in ref.)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":43.94948,"origin":"79Br ↔ Cl, halogen exchange (typically -Br +Cl)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":43.98983,"origin":"± CO2","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":44.02622,"origin":"-[C2H4O]-; polyethylene glycol, PEG, and related components such as Tritons and Tween buffers","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":45.94744,"origin":"81Br ↔ Cl, halogen exchange (typically -Br +Cl)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":47.96699,"origin":"± SO, sulfur compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":49.99681,"origin":"-[CF2]-, from perfluoro compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":52.91526,"origin":"79Br ↔ CN, halogen exchange with cyano group","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":53.00323,"origin":"NH4Cl salt adducts/clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":54.91322,"origin":"81Br ↔ CN, halogen exchange with cyano group","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":56.0626,"origin":"± C4H8, butylation","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":57.95862,"origin":"NaCl, sodium chloride clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":58.00548,"origin":"± CO2CH2","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":58.04187,"origin":"-[C3H6O]-; polypropylene glycol and related compounds, PPG, and related compounds, '+C3H6O, acetone condensation","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":61.9156,"origin":"79Br ↔ OH, halogen exchange with hydroxy group (typically -Br + OH)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":63.03203,"origin":"CHOONH4, ammonium formate adducts/clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":63.91355,"origin":"81Br ↔ OH, halogen exchange with hydroxy group (typically -Br + OH)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":63.9619,"origin":"± SO2, sulfur compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":63.99829,"origin":"-CH3SOH, specific loss from singly oxidized methionine residues","Ref.":"https://doi.org/10.1073/pnas.92.11.5072","mode":"both"}
{"PMD":67.98742,"origin":"CHOONa, sodium formate adducts/clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":72.03953,"origin":"-OH replacement with -OSi(CH3)3,(=[C3H8Si]), trimethylsiloxane, endcapping reagent","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":73.93256,"origin":"KCl adducts/clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":74.01879,"origin":"-[O-Si(CH3)2]-, polysiloxane, silicone rubber polymer (typical series at m/z's 355, 429, 503, 593, 667, 741, 815)","Ref.":"https://doi.org/10.1002/jms.465","mode":"both"}
{"PMD":77.91051,"origin":"79Br ↔ H, halogen exchange","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":78.01394,"origin":"C2H6OS, DMSO adducts/clusters, dimethylsulfoxide solvent","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":79.90847,"origin":"81Br ↔ H, halogen exchange","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":79.95682,"origin":"± SO3, sulfur compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":82.00307,"origin":"NaCH3CO2, sodium acetate clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":84.05159,"origin":"C2D6OS, deuterated DMSO adducts/clusters, NMR solvent","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":91.93562,"origin":"I ↔ Cl, halogen exchange (typically -I +Cl)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":97.96738,"origin":"± H2SO4, sulfur compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":97.9769,"origin":"± H3PO4, phosphorous compounds","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":100.9014,"origin":"I ↔ CN, halogen exchange with cyano group","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":106.90509,"origin":"107Ag, silver clusters in MALDI analysis of non-polar polymers, together with 109Ag  (~1:1)","Ref.":"https://doi.org/10.1016/S1044-0305(01)00225-2","mode":"pos"}
{"PMD":108.90476,"origin":"109Ag, silver clusters in MALDI analysis of non-polar polymers, togethre with 107Ag ( ~1:1)","Ref.":"https://doi.org/10.1016/S1044-0305(01)00225-2","mode":"pos"}
{"PMD":109.90173,"origin":"I ↔ OH, halogen exchange with hydroxy group (typically -I + OH)","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":113.99286,"origin":"CF3COOH, trifluoroacetic acid, TFA adducts/clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"neg"}
{"PMD":121.93828,"origin":"NaClO4, sodium perchlorate adducts/clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"neg"}
{"PMD":125.89665,"origin":"I ↔ H, halogen exchange","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":135.97481,"origin":"NaCF3CO2, sodium trifluoroacetate clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":146.05791,"origin":"± [Deoxy-Hexose-H2O, C6O4H10], e.g. Fucose","Ref.":"www.ionsource.com; Carbohydrate marker ions","mode":"both"}
{"PMD":162.05282,"origin":"-[C6H10O5]-, polysaccharides residues","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"pos"}
{"PMD":162.05282,"origin":"± [Hexose-H2O, C6O5H10], e.g. Glucose, Galactose, Mannose, Fructose","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":164.06848,"origin":"± [Deoxy-Hexose-H2O, C6O5H12], e.g. Fucose","Ref.":"www.ionsource.com; Carbohydrate marker ions","mode":"both"}
{"PMD":176.03209,"origin":"± [Glucuronic acid-H2O, C6O6H8]","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":180.06339,"origin":"± [Hexose, C6O6H12], e.g. Glucose, Galactose, Mannose, Fructose","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":194.04265,"origin":"± [Glucuronic acid, C6O7H10]","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":203.07937,"origin":"± [HexNAc-H2O, C8O5NH13], N-acetylhexoseamine","Ref.":"www.ionsource.com; Carbohydrate marker ions","mode":"both"}
{"PMD":206.05791,"origin":"+ sinapic acid - H2O, (C11H12O5-H2O), MALDI-matrix for proteins, possible photo- or condensation adduct","Ref.":"https://doi.org/10.1021/ac00216a020","mode":"both"}
{"PMD":221.08994,"origin":"± [HexNAc, C8O6NH15], N-acetylhexoseamine","Ref.":"www.ionsource.com; Carbohydrate marker ions","mode":"both"}
{"PMD":226.16813,"origin":"-[C12H22N2O2]-, cyclic oligomers from polyamide 66 (series observed with m/z 453, 679, 905)","Ref.":"https://doi.org/10.1016/j.jasms.2006.01.008","mode":"pos"}
{"PMD":259.80992,"origin":"CsI, cesium iodide clusters, used as calibration","Ref.":"https://doi.org/10.1002/rcm.1290050612","mode":"pos"}
{"PMD":288.13713,"origin":"C12H25SO4Na, sodium dodecylsulfate (SDS), adducts/clusters","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"neg"}
{"PMD":289.07324,"origin":"± [Glutathione-H2O, C10O5N3SH15]","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":291.09542,"origin":"± [Neu5Ac-H2O, C11O8NH17], N-acetylneuraminic acid, sialic acid, NANA","Ref.":"www.ionsource.com; Carbohydrate marker ions","mode":"both"}
{"PMD":305.06816,"origin":"± [Glutathione+O-H2O, C10O6N3SH15]","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":307.08381,"origin":"± [Glutathione, C10O6N3SH17]","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":309.10598,"origin":"± [Neu5Ac, C11O9NH19], N-acetylneuraminic acid, sialic acid, NANA","Ref.":"www.ionsource.com; Carbohydrate marker ions","mode":"both"}
{"PMD":324.10565,"origin":"± [Sucrose-H2O, C12O10H20]","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":342.11622,"origin":"± [Sucrose, C12O11H22]","Ref.":"https://doi.org/10.1016/S1044-0305(99)00090-2","mode":"both"}
{"PMD":484.17101,"origin":"+Tetraphenyl-tetramethyl-trisiloxane, (C28H32O2Si3), ( from silicon-based diffusion pump oil (DC7040, Dow corning)","Ref.":"https://doi.org/10.1063/1.1148310","mode":"both"}
{"PMD":546.18666,"origin":"+Pentaphenyl-trimethyl-trisiloxane, (C33H34O2Si3), ( from silicon-based diffusion pump oil (DC7050, Dow corning)","Ref.":"https://doi.org/10.1063/1.1148310","mode":"both"}