Discrepancies in reporting the CAG repeat lengths for Huntington's disease.

Huntington's disease results from a CAG repeat expansion within the Huntingtin gene; this is measured routinely in diagnostic laboratories. The European Huntington's Disease Network REGISTRY project centrally measures CAG repeat lengths on fresh samples; these were compared with the original results from 121 laboratories across 15 countries. We report on 1326 duplicate results; a discrepancy in reporting the upper allele occurred in 51% of cases, this reduced to 13.3% and 9.7% when we applied acceptable measurement errors proposed by the American College of Medical Genetics and the Draft European Best Practice Guidelines, respectively. Duplicate results were available for 1250 lower alleles; discrepancies occurred in 40% of cases. Clinically significant discrepancies occurred in 4.0% of cases with a potential unexplained misdiagnosis rate of 0.3%. There was considerable variation in the discrepancy rate among 10 of the countries participating in this study. Out of 1326 samples, 348 were re-analysed by an accredited diagnostic laboratory, based in Germany, with concordance rates of 93% and 94% for the upper and lower alleles, respectively. This became 100% if the acceptable measurement errors were applied. The central laboratory correctly reported allele sizes for six standard reference samples, blind to the known result. Our study differs from external quality assessment (EQA) schemes in that these are duplicate results obtained from a large sample of patients across the whole diagnostic range. We strongly recommend that laboratories state an error rate for their measurement on the report, participate in EQA schemes and use reference materials regularly to adjust their own internal standards

Discrepancies in reporting the CAG repeat lengths for Huntington's disease.

Huntington's disease results from a CAG repeat expansion within the Huntingtin gene; this is measured routinely in diagnostic laboratories. The European Huntington's Disease Network REGISTRY project centrally measures CAG repeat lengths on fresh samples; these were compared with the original results from 121 laboratories across 15 countries. We report on 1326 duplicate results; a discrepancy in reporting the upper allele occurred in 51% of cases, this reduced to 13.3% and 9.7% when we applied acceptable measurement errors proposed by the American College of Medical Genetics and the Draft European Best Practice Guidelines, respectively. Duplicate results were available for 1250 lower alleles; discrepancies occurred in 40% of cases. Clinically significant discrepancies occurred in 4.0% of cases with a potential unexplained misdiagnosis rate of 0.3%. There was considerable variation in the discrepancy rate among 10 of the countries participating in this study. Out of 1326 samples, 348 were re-analysed by an accredited diagnostic laboratory, based in Germany, with concordance rates of 93% and 94% for the upper and lower alleles, respectively. This became 100% if the acceptable measurement errors were applied. The central laboratory correctly reported allele sizes for six standard reference samples, blind to the known result. Our study differs from external quality assessment (EQA) schemes in that these are duplicate results obtained from a large sample of patients across the whole diagnostic range. We strongly recommend that laboratories state an error rate for their measurement on the report, participate in EQA schemes and use reference materials regularly to adjust their own internal standards

Observing Huntington's disease: the European Huntington's Disease Network's REGISTRY.

none642sinoneOrth M, Handley OJ, Schwenke C, Dunnett S, Wild EJ, Tabrizi SJ, Landwehrmeyer GB, Bachoud-Lévi AC, Bentivoglio AR, Biunno I, Bonelli R, Burgunder JM, Dunnett SB, Ferreira JJ, Giuliano J, Handley OJ, Heiberg A, Illmann T, van Kammen D, Landwehrmeye GB, Levey J, Nielsen JE, Päivärinta M, Roos RA, Sebastián AR, Tabrizi SJ, Vandenberghe W, Verellen-Dumoulin C, Zaremba J, Uhrova T, Wahlström J, Schwenke C, Orth M, Illmann T, Wallner M, Barth K, Guedes LC, Finisterra AM, Garde MB, Bos R, Burg S, Ecker D, Handley OJ, Held C, Koppers K, Laurà M, Descals AM, McLean T, Mestre T, Minster S, Monza D, Townhill J, Orth M, Padieu H, Paterski L, Peppa N, Koivisto SP, Rialland A, Røren N, Sasinková P, Cubillo PT, Tritsch C, van Walsem MR, Witjes-Ané MN, Yudina E, Zielonka D, Zielonka E, Zinzi P, Bonelli RM, Herranhof B, Holl A, Kapfhammer HP, Koppitz M, Magnet M, Otti D, Painold A, Reisinger K, Scheibl M, Hecht K, Lilek S, Müller N, Schöggl H, Ullah J, Brugger F, Hepperger C, Hotter A, Mahlknecht P, Nocker M, Seppi K, Wenning G, Buratti L, Hametner EM, Holas C, Hussl A, Mair K, Poewe W, Wolf E, Zangerl A, Braunwarth EM, Lilek S, Sinadinosa D, Walleczek AM, Bonelli RM, Ladurner G, Staffen W, Ribaï P, Verellen-Dumoulin C, Flamez A, Morez V, de Raedt S, Boogaerts A, Vandenberghe W, van Reijen D, Klempíř J, Kucharík M, Roth J, Šenkárová Z, Hasholt L, Hjermind LE, Jakobsen O, Nørremølle A, Sørensen SA, Stokholm J, Nielsen J, Hiivola H, Martikainen K, Tuuha K, Peippo M, Sipponen M, Ignatius J, Kärppä M, Åman J, Santala M, Allain P, Guérid MA, Gohier B, Olivier A, Prundean A, Scherer-Gagou C, Verny C, Babiloni B, Debruxelles S, Goizet C, Lafoucrière D, De Bruycker C, Carette AS, Decorte E, Delval A, Delliaux M, Dujardin K, Peter M, Plomhouse L, Simonin C, Thibault-Tanchou S, Bellonet M, Duru C, Krystkowiak P, Roussel M, Wannepain S, Azulay JP, Chabot C, Delphini M, Eusebio A, Grosjean H, Mundler L, Nowak M, Rudolf G, Steinmetz G, Tranchant C, Wagner C, Zimmermann MA, Calvas F, Cheriet S, Démonet JF, Galitzky M, Kosinski CM, Milkereit E, Probst D, Sass C, Schiefer J, Schlangen C, Werner CJ, Gelderblom H, Priller J, Prüss H, Spruth EJ, Andrich J, Hoffmann R, Kraus PH, Muth S, Prehn C, Saft C, Salmen S, Stamm C, Steiner T, Strassburger K, Lange H, Friedrich A, Hunger U, Löhle M, Schmidt S, Storch A, Wolz A, Wolz M, Lambeck J, Zucker B, Boelmans K, Ganos C, Hidding U, Lewerenz J, Münchau A, Orth M, Schmalfeld J, Stubbe L, Zittel S, Diercks G, Gorzolla H, Schrader C, Heinicke W, Ribbat M, Longinus B, Bürk K, Möller JC, Rissling I, Peinemann A, Städtler M, Weindl A, Bechtel N, Beckmann H, Bohlen S, Hölzner E, Lange H, Reilmann R, Rohm S, Rumpf S, Schepers S, Beister A, Dose M, Hammer K, Kieni J, Leythaeuser G, Marquard R, Raab T, Richter S, Selimbegovic-Turkovic A, Schrenk C, Schuierer M, Wiedemann A, Barth K, Buck A, Connemann J, Ecker D, Eschenbach C, Held C, Landwehrmeyer B, Lezius F, Nepper S, Niess A, Orth M, Süssmuth S, Trautmann S, Weydt P, Cormio C, Difruscolo O, Sciruicchio V, Serpino C, de Tommaso M, Capellari S, Cortelli P, Gallassi R, Poda R, Rizzo G, Scaglione C, Bertini E, Ghelli E, Ginestroni A, Massaro F, Mechi C, Paganini M, Piacentini S, Pradella S, Romoli AM, Sorbi S, Abbruzzese G, di Poggio MB, Di Maria E, Ferrandes G, Mandich P, Marchese R, Albanese A, Di Bella D, Di Donato S, Gellera C, Genitrini S, Mariotti C, Monza D, Nanetti L, Paridi D, Soliveri P, Tomasello C, De Michele G, Di Maio L, Rinaldi C, Russo CV, Salvatore E, Tucci T, Cannella M, Codella V, De Gregorio F, De Nicola N, Martino T, Simonelli M, Squitieri F, Bentivoglio AR, Catalli C, Di Giacopo R, Fasano A, Frontali M, Guidubaldi A, Ialongo T, Jacopini G, Loria G, Modoni A, Piano C, Chiara P, Quaranta D, Romano S, Soleti F, Spadaro M, Zinzi P, van Hout MS, van Vugt JP, de Weert AM, Bolwijn JJ, Dekker M, Leenders KL, van Oostrom JC, Bos R, Dumas EM, Jurgens CK, van den Bogaard SJ, Roos RA, 't Hart EP, Witjes-Ané MN, Kremer B, Verstappen CC, Heiberg A, van Walsem MR, Frich J, Wehus R, Aaserud O, Borgerød N, Bjørgo K, Fannemel M, Gørvell P, Pro Koivisto S, Retterstøl L, Overland T, Stokke B, Bjørnevoll I, Sando SB, Blinkenberg EØ, Hauge E, Tyvoll H, Sitek E, Slawek J, Soltan W, Boczarska-Jedynak M, Jasinska-Myga B, Opala G, Kłodowska-Duda G, Banaszkiewicz K, Szczudlik A, Rudzińska M, Wójcik M, Dec M, Krawczyk M, Bryl A, Ciesielska A, Klimberg A, Marcinkowski J, Sempołowicz J, Zielonka D, Samara H, Janik P, Kalbarczyk A, Kwiecinski H, Jamrozik Z, Antczak J, Jachinska K, Rakowicz M, Richter P, Ryglewicz D, Witkowski G, Zdzienicka E, Zaremba J, Sułek A, Krysa W, Júlio F, Januário C, Mestre T, Guedes L, Coelho M, Mendes T, Valadas A, Ferreira JJ, Timóteo Â, Costa C, Vale J, Cavaco S, Damásio J, Magalhães M, Gago M, Garrett C, Guerra MR, Solis P, Herrera CD, Garcia PM, Barrero F, Morales B, Cubo E, Mariscal N, Alonso-Frech F, Perez MR, Fenollar M, García RG, Quiroga PP, Rivera SV, Villanueva C, Bascuñana M, Ventura MF, Ribas GG, de Yébenes JG, Moreno JL, Cubillo PT, Ruíz PJ, Martínez-Descals A, Artiga MJ, Sánchez V, Perea MF, Lorenza F, Torres MM, Reinante G, Moreau LV, Barbera MA, Guia DB, Hernanz LC, Catena JL, Sebastián AR, Ferrer PQ, Carruesco GT, Bas J, Busquets N, Calopa M, Buongiorno MT, Muñoz E, Elorza MD, López CD, Terol SD, Robert MF, Ruíz BG, Casado AG, Martínez IH, Viladrich CM, Pons i Càrdenas R, Roca E, Llesoy JR, Idiago JM, Vergara MR, García SS, Villa Riballo A, González SG, Guisasola LM, Salvador C, San Martín ES, Gorospe A, Legarda I, Arques PN, Rodríguez MJ, Vives B, Gaston I, Ramos-Arroyo MA, Moreno JM, Peña JC, Avarvarei LD, Bastida AM, Recio MF, Vergé LR, Sánchez VS, Carrillo F, Cáceres MT, Mir P, Suarez MJ, Bosca M, Burguera JA, Garcia AC, Martínez LM, del Val JL, Loutfi G, Olofsson C, Stattin EL, Westman L, Wikström B, Höglund A, Pålhagen SE, Paucar M, Sandström B, Soltani R, Svenningsson P, Reza-Soltani TW, Constantinescu R, Fredlund G, Høsterey-Ugander U, Neleborn-Lingefjärd L, Wahlström J, Esmaeilzadeh M, Tedroff J, Winnberg E, Björn Y, Ekwall C, Gøller ML, Johansson A, Wiklund L, Petersen Å, Reimer J, Widner H, Burgunder JM, Burgunder Y, Stebler Y, Kaelin A, Romero I, Schüpbach M, Zaugg SW, Jack R, Matheson K, Miedzybrodzka Z, Rae D, Simpson S, Summers F, Ure A, Crooks J, Curtis A, de Souza Keylock J, Rickards H, Wright J, Hayward B, Sieradzan K, Wright A, Barker RA, Di Pietro A, Fisher K, Goodman A, Hill S, Kershaw A, Mason S, Paterson N, Raymond L, Bisson J, Busse M, Clenaghan C, Ellison-Rose L, Handley O, Hunt S, Townhill J, Price K, Rosser A, Edwards M, Hughes T, McGill M, Pearson P, Porteous M, Smith P, Zeman A, Causley A, Harrower T, Howcroft D, Lambord N, Rankin J, Brockie P, Foster J, Johns N, McKenzie S, Rothery J, Thomas G, Yates S, Miller J, Ritchie S, Burrows L, Fletcher A, Harding A, Laver F, Silva M, Thomson A, Burns P, Chu C, Evans C, Hamer S, Markova I, Miller J, Raman A, Barnes K, Chu C, Hobson E, Jamieson S, Markova I, Thomson J, Toscano J, Wild S, Yardumian P, Bourne C, Clayton C, Dipple H, Clapton J, Grant D, Hallam C, Middleton J, Murch A, Patino D, Bate L, Pate L, Andrews T, Dougherty A, Kavalier F, Golding C, Lashwood A, Robertson D, Ruddy D, Whaite A, Patton M, Peterson M, Rose S, Andrews T, Bruno S, Chu E, Doherty K, Golding, Fillingham K, Foustanos I, O'Donovan K, Peppa N, Tidswell K, Quarrell O.Orth, M; Handley, Oj; Schwenke, C; Dunnett, S; Wild, Ej; Tabrizi, Sj; Landwehrmeyer, Gb; Bachoud-Lévi, Ac; Bentivoglio, Ar; Biunno, I; Bonelli, R; Burgunder, Jm; Dunnett, Sb; Ferreira, Jj; Giuliano, J; Handley, Oj; Heiberg, A; Illmann, T; van Kammen, D; Landwehrmeye, Gb; Levey, J; Nielsen, Je; Päivärinta, M; Roos, Ra; Sebastián, Ar; Tabrizi, Sj; Vandenberghe, W; Verellen-Dumoulin, C; Zaremba, J; Uhrova, T; Wahlström, J; Schwenke, C; Orth, M; Illmann, T; Wallner, M; Barth, K; Guedes, Lc; Finisterra, Am; Garde, Mb; Bos, R; Burg, S; Ecker, D; Handley, Oj; Held, C; Koppers, K; Laurà, M; Descals, Am; Mclean, T; Mestre, T; Minster, S; Monza, D; Townhill, J; Orth, M; Padieu, H; Paterski, L; Peppa, N; Koivisto, Sp; Rialland, A; Røren, N; Sasinková, P; Cubillo, Pt; Tritsch, C; van Walsem, Mr; Witjes-Ané, Mn; Yudina, E; Zielonka, D; Zielonka, E; Zinzi, P; Bonelli, Rm; Herranhof, B; Holl, A; Kapfhammer, Hp; Koppitz, M; Magnet, M; Otti, D; Painold, A; Reisinger, K; Scheibl, M; Hecht, K; Lilek, S; Müller, N; Schöggl, H; Ullah, J; Brugger, F; Hepperger, C; Hotter, A; Mahlknecht, P; Nocker, M; Seppi, K; Wenning, G; Buratti, L; Hametner, Em; Holas, C; Hussl, A; Mair, K; Poewe, W; Wolf, E; Zangerl, A; Braunwarth, Em; Lilek, S; Sinadinosa, D; Walleczek, Am; Bonelli, Rm; Ladurner, G; Staffen, W; Ribaï, P; Verellen-Dumoulin, C; Flamez, A; Morez, V; de Raedt, S; Boogaerts, A; Vandenberghe, W; van Reijen, D; Klempíř, J; Kucharík, M; Roth, J; Šenkárová, Z; Hasholt, L; Hjermind, Le; Jakobsen, O; Nørremølle, A; Sørensen, Sa; Stokholm, J; Nielsen, J; Hiivola, H; Martikainen, K; Tuuha, K; Peippo, M; Sipponen, M; Ignatius, J; Kärppä, M; Åman, J; Santala, M; Allain, P; Guérid, Ma; Gohier, B; Olivier, A; Prundean, A; Scherer-Gagou, C; Verny, C; Babiloni, B; Debruxelles, S; Goizet, C; Lafoucrière, D; De Bruycker, C; Carette, As; Decorte, E; Delval, A; Delliaux, M; Dujardin, K; Peter, M; Plomhouse, L; Simonin, C; Thibault-Tanchou, S; Bellonet, M; Duru, C; Krystkowiak, P; Roussel, M; Wannepain, S; Azulay, Jp; Chabot, C; Delphini, M; Eusebio, A; Grosjean, H; Mundler, L; Nowak, M; Rudolf, G; Steinmetz, G; Tranchant, C; Wagner, C; Zimmermann, Ma; Calvas, F; Cheriet, S; Démonet, Jf; Galitzky, M; Kosinski, Cm; Milkereit, E; Probst, D; Sass, C; Schiefer, J; Schlangen, C; Werner, Cj; Gelderblom, H; Priller, J; Prüss, H; Spruth, Ej; Andrich, J; Hoffmann, R; Kraus, Ph; Muth, S; Prehn, C; Saft, C; Salmen, S; Stamm, C; Steiner, T; Strassburger, K; Lange, H; Friedrich, A; Hunger, U; Löhle, M; Schmidt, S; Storch, A; Wolz, A; Wolz, M; Lambeck, J; Zucker, B; Boelmans, K; Ganos, C; Hidding, U; Lewerenz, J; Münchau, A; Orth, M; Schmalfeld, J; Stubbe, L; Zittel, S; Diercks, G; Gorzolla, H; Schrader, C; Heinicke, W; Ribbat, M; Longinus, B; Bürk, K; Möller, Jc; Rissling, I; Peinemann, A; Städtler, M; Weindl, A; Bechtel, N; Beckmann, H; Bohlen, S; Hölzner, E; Lange, H; Reilmann, R; Rohm, S; Rumpf, S; Schepers, S; Beister, A; Dose, M; Hammer, K; Kieni, J; Leythaeuser, G; Marquard, R; Raab, T; Richter, S; Selimbegovic-Turkovic, A; Schrenk, C; Schuierer, M; Wiedemann, A; Barth, K; Buck, A; Connemann, J; Ecker, D; Eschenbach, C; Held, C; Landwehrmeyer, B; Lezius, F; Nepper, S; Niess, A; Orth, M; Süssmuth, S; Trautmann, S; Weydt, P; Cormio, C; Difruscolo, O; Sciruicchio, V; Serpino, C; de Tommaso, M; Capellari, S; Cortelli, P; Gallassi, R; Poda, R; Rizzo, G; Scaglione, C; Bertini, E; Ghelli, E; Ginestroni, A; Massaro, F; Mechi, C; Paganini, M; Piacentini, S; Pradella, S; Romoli, Am; Sorbi, S; Abbruzzese, G; di Poggio, Mb; Di Maria, E; Ferrandes, G; Mandich, P; Marchese, R; Albanese, A; Di Bella, D; Di Donato, S; Gellera, C; Genitrini, S; Mariotti, C; Monza, D; Nanetti, L; Paridi, D; Soliveri, P; Tomasello, C; De Michele, G; Di Maio, L; Rinaldi, C; Russo, Cv; Salvatore, E; Tucci, T; Cannella, M; Codella, V; De Gregorio, F; De Nicola, N; Martino, T; Simonelli, M; Squitieri, F; Bentivoglio, Ar; Catalli, C; Di Giacopo, R; Fasano, A; Frontali, M; Guidubaldi, A; Ialongo, T; Jacopini, G; Loria, G; Modoni, A; Piano, C; Chiara, P; Quaranta, D; Romano, S; Soleti, F; Spadaro, M; Zinzi, P; van Hout, Ms; van Vugt, Jp; de Weert, Am; Bolwijn, Jj; Dekker, M; Leenders, Kl; van Oostrom, Jc; Bos, R; Dumas, Em; Jurgens, Ck; van den Bogaard, Sj; Roos, Ra; 't Hart, Ep; Witjes-Ané, Mn; Kremer, B; Verstappen, Cc; Heiberg, A; van Walsem, Mr; Frich, J; Wehus, R; Aaserud, O; Borgerød, N; Bjørgo, K; Fannemel, M; Gørvell, P; Pro Koivisto, S; Retterstøl, L; Overland, T; Stokke, B; Bjørnevoll, I; Sando, Sb; Blinkenberg, Eø; Hauge, E; Tyvoll, H; Sitek, E; Slawek, J; Soltan, W; Boczarska-Jedynak, M; Jasinska-Myga, B; Opala, G; Kłodowska-Duda, G; Banaszkiewicz, K; Szczudlik, A; Rudzińska, M; Wójcik, M; Dec, M; Krawczyk, M; Bryl, A; Ciesielska, A; Klimberg, A; Marcinkowski, J; Sempołowicz, J; Zielonka, D; Samara, H; Janik, P; Kalbarczyk, A; Kwiecinski, H; Jamrozik, Z; Antczak, J; Jachinska, K; Rakowicz, M; Richter, P; Ryglewicz, D; Witkowski, G; Zdzienicka, E; Zaremba, J; Sułek, A; Krysa, W; Júlio, F; Januário, C; Mestre, T; Guedes, L; Coelho, M; Mendes, T; Valadas, A; Ferreira, Jj; Timóteo, Â; Costa, C; Vale, J; Cavaco, S; Damásio, J; Magalhães, M; Gago, M; Garrett, C; Guerra, Mr; Solis, P; Herrera, Cd; Garcia, Pm; Barrero, F; Morales, B; Cubo, E; Mariscal, N; Alonso-Frech, F; Perez, Mr; Fenollar, M; García, Rg; Quiroga, Pp; Rivera, Sv; Villanueva, C; Bascuñana, M; Ventura, Mf; Ribas, Gg; de Yébenes, Jg; Moreno, Jl; Cubillo, Pt; Ruíz, Pj; Martínez-Descals, A; Artiga, Mj; Sánchez, V; Perea, Mf; Lorenza, F; Torres, Mm; Reinante, G; Moreau, Lv; Barbera, Ma; Guia, Db; Hernanz, Lc; Catena, Jl; Sebastián, Ar; Ferrer, Pq; Carruesco, Gt; Bas, J; Busquets, N; Calopa, M; Buongiorno, Mt; Muñoz, E; Elorza, Md; López, Cd; Terol, Sd; Robert, Mf; Ruíz, Bg; Casado, Ag; Martínez, Ih; Viladrich, Cm; Pons, i Càrdenas R; Roca, E; Llesoy, Jr; Idiago, Jm; Vergara, Mr; García, Ss; Villa Riballo, A; González, Sg; Guisasola, Lm; Salvador, C; San Martín, Es; Gorospe, A; Legarda, I; Arques, Pn; Rodríguez, Mj; Vives, B; Gaston, I; Ramos-Arroyo, Ma; Moreno, Jm; Peña, Jc; Avarvarei, Ld; Bastida, Am; Recio, Mf; Vergé, Lr; Sánchez, Vs; Carrillo, F; Cáceres, Mt; Mir, P; Suarez, Mj; Bosca, M; Burguera, Ja; Garcia, Ac; Martínez, Lm; del Val, Jl; Loutfi, G; Olofsson, C; Stattin, El; Westman, L; Wikström, B; Höglund, A; Pålhagen, Se; Paucar, M; Sandström, B; Soltani, R; Svenningsson, P; Reza-Soltani, Tw; Constantinescu, R; Fredlund, G; Høsterey-Ugander, U; Neleborn-Lingefjärd, L; Wahlström, J; Esmaeilzadeh, M; Tedroff, J; Winnberg, E; Björn, Y; Ekwall, C; Gøller, Ml; Johansson, A; Wiklund, L; Petersen, Å; Reimer, J; Widner, H; Burgunder, Jm; Burgunder, Y; Stebler, Y; Kaelin, A; Romero, I; Schüpbach, M; Zaugg, Sw; Jack, R; Matheson, K; Miedzybrodzka, Z; Rae, D; Simpson, S; Summers, F; Ure, A; Crooks, J; Curtis, A; de Souza Keylock, J; Rickards, H; Wright, J; Hayward, B; Sieradzan, K; Wright, A; Barker, Ra; Di Pietro, A; Fisher, K; Goodman, A; Hill, S; Kershaw, A; Mason, S; Paterson, N; Raymond, L; Bisson, J; Busse, M; Clenaghan, C; Ellison-Rose, L; Handley, O; Hunt, S; Townhill, J; Price, K; Rosser, A; Edwards, M; Hughes, T; Mcgill, M; Pearson, P; Porteous, M; Smith, P; Zeman, A; Causley, A; Harrower, T; Howcroft, D; Lambord, N; Rankin, J; Brockie, P; Foster, J; Johns, N; Mckenzie, S; Rothery, J; Thomas, G; Yates, S; Miller, J; Ritchie, S; Burrows, L; Fletcher, A; Harding, A; Laver, F; Silva, M; Thomson, A; Burns, P; Chu, C; Evans, C; Hamer, S; Markova, I; Miller, J; Raman, A; Barnes, K; Chu, C; Hobson, E; Jamieson, S; Markova, I; Thomson, J; Toscano, J; Wild, S; Yardumian, P; Bourne, C; Clayton, C; Dipple, H; Clapton, J; Grant, D; Hallam, C; Middleton, J; Murch, A; Patino, D; Bate, L; Pate, L; Andrews, T; Dougherty, A; Kavalier, F; Golding, C; Lashwood, A; Robertson, D; Ruddy, D; Whaite, A; Patton, M; Peterson, M; Rose, S; Andrews, T; Bruno, S; Chu, E; Doherty, K; Golding, ; Fillingham, K; Foustanos, I; O'Donovan, K; Peppa, N; Tidswell, K; Quarrell, O

Optimization of adsorptive removal of α-toluic acid by CaO2 nanoparticles using response surface methodology

The present work addresses the optimization of process parameters for adsorptive removal of α-toluic acid by calcium peroxide (CaO2) nanoparticles using response surface methodology (RSM). CaO2 nanoparticles were synthesized by chemical precipitation method and confirmed by Transmission electron microscopy (TEM) and high-resolution TEM (HRTEM) analysis which shows the CaO2 nanoparticles size range of 5–15 nm. A series of batch adsorption experiments were performed using CaO2 nanoparticles to remove α-toluic acid from the aqueous solution. Further, an experimental based central composite design (CCD) was developed to study the interactive effect of CaO2 adsorbent dosage, initial concentration of α-toluic acid, and contact time on α-toluic acid removal efficiency (response) and optimization of the process. Analysis of variance (ANOVA) was performed to determine the significance of the individual and the interactive effects of variables on the response. The model predicted response showed a good agreement with the experimental response, and the coefficient of determination, (R2) was 0.92. Among the variables, the interactive effect of adsorbent dosage and the initial α-toluic acid concentration was found to have more influence on the response than the contact time. Numerical optimization of process by RSM showed the optimal adsorbent dosage, initial concentration of α-toluic acid, and contact time as 0.03 g, 7.06 g/L, and 34 min respectively. The predicted removal efficiency was 99.50%. The experiments performed under these conditions showed α-toluic acid removal efficiency up to 98.05%, which confirmed the adequacy of the model prediction