Prominent NUS professor loses job over misconduct allegations

SINGAPORE: Shawn Chen Xiaoyuan, a molecular imaging and nanomedicine expert with the National University of Singapore (NUS), has been dismissed. NUS confirmed the termination of Dr Chen due to violations of the university’s code of conduct for its staff to the South China Morning Post last week.

The dismissal came after a female PhD candidate accused the professor of several instances of physical and verbal misconduct in the first half of 2025.

Dr Chen has denied the allegations and announced that he plans on filing an appeal.

Who is Shawn Chen Xiaoyuan?

Dr Chen, 50, held appointments in the engineering and medical schools of NUS. Originally from Taixing, Jiangsu province, he is an alumnus of Nanjing University and the University of Idaho, where he earned his doctorate in chemistry in 1999.

Prior to joining NUS in 2020, he was an Assistant Professor at Stanford University and then a senior investigator and lab chief at the US National Institutes of Health.

Dr Chen published over 850 peer-reviewed papers and is the founding editor of the journal “Theranostics.” Among other distinctions, he has served as president of the Chinese-American Society of Nuclear Medicine and Molecular Imaging and the Chinese American Society of Nanomedicine and Nanobiotechnology.

The accusations against Dr Chen

The student in question had joined Dr Chen’s lab in March 2024. She filed a complaint against him on June 25, 2025, saying that his behaviour toward her that lasted over several months had been inappropriate and caused her to become offended, uncomfortable, and mentally distressed.

NUS then launched an investigation and hearing, which resulted in Dr Chen’s termination.

The student, who also took to social media to air her allegations, has been transferred to another lab at NUS.

SCMP reported that the university responded to her post in an email, writing, “The various instances of physical contact over several months were unsolicited and unwanted, causing you discomfort, offence, and distress. The university concluded that termination of his employment was appropriate.”

Dr Chen’s response

Immediately after his dismissal was announced, Dr Chen said that he would appeal the termination of his tenure.

“I deny the complainant’s allegations, and I am unable to comment further because I intend to pursue the appeals process and my legal remedies,” SCMP quotes him as saying.

Moreover, a group calling itself “Chen Xiaoyuan Team” has posted on Chinese social media, also denying the student’s accusations and making allegations about her behaviour, calling into question her professionalism. /TISG

Read also: 4th NUS professor fired over inappropriate behaviour (sexual misconduct) in 18 months, Netizens ask ‘Why NUS so many cases?’