By the same authors

From the same journal

Direct Observation of Photochemical Free Radical Production from the Sunscreen 2‐Phenylbenzimidazole‐5‐Sulfonic Acid via Laser‐Interfaced Mass Spectrometry

Research output: Contribution to journalArticlepeer-review

Full text download(s)

Published copy (DOI)



Publication details

DateAccepted/In press - 12 Aug 2019
DateE-pub ahead of print (current) - 12 Aug 2019
Number of pages7
Early online date12/08/19
Original languageEnglish


The common sunscreen molecule 2‐phenylbenzimidazole‐5‐sulfonic acid (PBSA) is studied in its gas‐phase deprotonated form ([PBSA‐H]−) for the first time as an important step in achieving a better understanding of its behavior as a photosensitizer. UV laser‐interfaced mass spectrometry is employed, revealing that [PBSA‐H]− photofragments into three ionic products (m/z 208, 193, and 80) with distinctive wavelength‐dependent production profiles. Both the m/z 208 and 80 channels produce associated neutral free radical species. Collision‐induced dissociation is performed on [PBSA‐H]−, showing that its hot ground‐state dissociates only into m/z 193 (statistical fragment). Therefore, the m/z 208 and 80 fragments which are produced strongly through the UVA/UVB are characterized as non‐statistical photofragments associated with non‐ergodic excited‐state decay. Our observation of non‐statistical photofragments reveal that [PBSA‐H]− is not behaving as a model sunscreen molecule. Further, our results indicate that the T1 state, associated with photosensitization, decays with direct free radical production.

Bibliographical note

Uploaded with permission of the publisher/copyright holder. Further copying may not be permitted; contact the publisher for details

    Research areas

  • Free radicals, LASER SPECTROSCOPY, Photolysis, Photosensitizer, Sunscreen Molecules


Discover related content

Find related publications, people, projects, datasets and more using interactive charts.

View graph of relations