title: Comparison of binder compositions in Pompeian wall painting styles from Insula Occidentalis.
abstract: BACKGROUND
  Although the pigment composition of Pompeian wall paintings has been the object of several studies, a comprehensive characterization of paint binder components is still lacking. This work aimed investigated at a molecular level the binder composition differences among wall paintings belonging to different periods of Pompeii's history. Analytical investigations were performed on representative samples of the first, second, third, and fourth painting styles excavated from the house of Marcus Fabius Rufus (Insula Occidentalis). The application of sensitive experimental methodologies was complemented by historical knowledge to gain insight in painting techniques and materials used by Pompeian artists.
  
  
  RESULTS
  Fourier transform infrared spectroscopy and Raman spectroscopy were used to investigate the organic components and pigments present in powders obtained from samples of the four painting styles. No proteinaceous components were detected in the samples with liquid chromatography-electrospray ionization-hybrid quadrupole/time-of-flight mass spectrometry. Liquid chromatography, gas chromatography with flame-ionization detection, and gas chromatography-mass spectrometry of polar and non-polar components extracted from powders were used to evaluate and compare the free amino acids, sugars, and fatty acids profiles.
  
  
  CONCLUSIONS
  Pigments and natural products (lipids, gums and wheat flours) were the main components of all samples. This supports the hypothesis that artists likely used water tempera for Pompeian wall paintings. Graphical AbstractScheme of the multi-analytical approach followed to compare Pompeian paint binders composition.Scheme of the multi-analytical approach followed to compare Pompeian paint binders composition.
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Via Pansini 5, I-80131 Naples, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Gelzo
authors.affiliation: Centro Internazionale per gli Studi Pompeiani, Università Suor Orsola Benincasa, Via Suor Orsola 10, I-80135 Naples, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Grimaldi
authors.affiliation: Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Via Cintia 21, I-80126 Naples, Italy ; Distretto ad Alta Tecnologia dei Beni Culturali (DATABENC) Scarl, Naples, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Vergara
authors.affiliation: Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, I-81100 Caserta, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Severino
authors.affiliation: Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, I-81100 Caserta, Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Chambery
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Via Pansini 5, I-80131 Naples, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Dello Russo
authors.affiliation: AIES Beni culturali, I-80055 Portici, Napoli, Italy.
authors.forename: Ciro
authors.initials: C
authors.lastname: Piccioli
authors.affiliation: Dipartimento di Medicina Clinica e Sperimentale, Università di Foggia, Via Pinto 1, I-71122 Foggia, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Corso
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Via Pansini 5, I-80131 Naples, Italy ; CEINGE, Biotecnologie Avanzate Scarl, Via Comunale Margherita, 482 I-80145 Naples, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Arcari
keywords: Binder analysis; Cultural heritage; Mass spectrometry; Pompeian wall painting; Spectroscopy