¹Division of Biochemistry, Department of Basic Pharmaceutical Sciences, Faculty of Pharmacy, University of Health Sciences, 34668 Istanbul, Türkiye DOI : 10.29228/jrp.511 The reducing property of collagen was employed for the synthesis of gold nanoparticles (AuNPs) without the use of any toxic chemicals. The morphology of the resulting AuNPs-collagen particles appeared in spherical and triangular nanoprisms with sizes ranging from 30-60 nm, as observed in TEM results. Increasing the synthesis temperature led to the growth of AuNPs. Surface-enhanced Raman Spectroscopy studies revealed that amide I and carboxylic acid group vibrations indicated collagen binding to the Au surface through these groups. The AuNPscollagen nanocomposite was tested for its antimicrobial properties against eight different microorganisms and it exhibited antibacterial properties solely against the Gordonia rubripertincta bacterium. Keywords : gold nanoparticles; collagen; cosmetic formulations; nanoparticle synthesis; skincare innovation