Contents lists available at ScienceDirect Materials Science & Engineering C journal homepage: www.elsevier.com/locate/msec Hybrid folic acid-conjugated gold nanorods-loaded human serum albumin nanoparticles for simultaneous photothermal and chemotherapeutic therapy David Encinas-Basurto a , Jaime Ibarra a , Josué Juarez a , Alberto Pardo b , Silvia Barbosa b , Pablo Taboada b, ⁎ , Miguel A. Valdez a a Departamento de Física, Posgrado en Nanotecnología, Universidad de Sonora, Rosales y Transversal, 83000 Hermosillo, Sonora, Mexico b Departamento de Física de la Materia Condensada, Facultad de Física, Universidad de Santiago de Compostela, Spain ARTICLE INFO Keywords: Hybrid nanoparticles Human serum albumin Folic acid Drug delivery Photothermal therapy ABSTRACT Hybrid nanoparticles containing both structural and functional nanocomponents might result in higher success and increased quality of life for patients suffering a disease such as cancer. In this study, we combine che- motherapy of conventional drug doxorubicin (Dox) with gold nanorods (AuNR) for photothermal therapy using multifunctional human serum albumin nanoparticles (HSA NP's) fabricated via desolvation technique with high efficiency. Folic acid (FA) was conjugated to HSA NP's trough an amidation via carbodiimide reaction for a more specific nanoplataform to HeLa cancer cells. The loading efficiency of Dox into AuNR loaded-HSA NP reached up to 2 μg Dox/mg HSA. The HSA-AuNR-Dox NP experienced photothermal heating varying laser potency (1, 0.5 and 0.2 W); reaching the bulk particle solution an increment of 16, 8 and 6 °C after 10 min of near-IR laser exposure respectively. When HeLa cells were treated with this multifunctional nanoplataform containing only AuNR, cancer cells experienced 96% cell viability without irradiation and 55% cell viability after just one ir- radiation session. When Dox is present in the nanoplataform, viability were 60% and 24% for non-irradiated and irradiated nanoplataforms, respectively. This study demonstrates that HSA-AuNR-Dox nanoparticles are suitable systems allowing a synergic chemo and phothothermal therapy. 1. Introduction The emergence of nanotechnology and its application to the bio- medical field has originated the development of new biocompatible nanoscale drug carriers as liposomes and polymeric nanoparticles, which improve the therapeutic efficacy of multiple drugs [1]. Drug- loaded nanocarriers have many advantages in comparison with the administration of free drugs, particularly at the systemic level such as a longer circulation half-life times, improved pharmacokinetics due to the enhanced permeability and retention effect (EPR) and diminished ad- verse side effects [2–4]. Despite their success, nevertheless there is a current need for multi-functional, temporally active cancer treatments which maximize therapeutic effects through less invasive techniques. Hybrid nanoparticles containing both structural and functional nano- components might result in higher success rates and increased life quality of patients suffering a disease as cancer. The structural com- ponents of hybrid nanoparticles can be mainly classified based on the therapeutic function they possess. For example, structural nano- components such as liposomes, polymeric micelles, mesoporous silica, gels, or viruses can carry mainly a drug cargo; while functional nanocomponents such as gold nanoparticles or carbon nanotubes en- able the application of photoablation therapy as a result of their out- standing optical properties. In this way, hybrid nanoparticles can retain the beneficial features of both type of nanomaterials and, at the same time, allow the systematic fine-tuning of their properties through the combination of functional components [5]. Dou et al. [6] combine up conversion NPs for delivery of doxorubicin and imaging for bioappli- cations against cancer cells. Ellis et al. [7] combined an biocompatible pH-responsive polymer anchored to gold NPs surface for enhancing cancer therapy. In particular, plasmonic noble metal nanoparticles (NPs) are dis- tinguished for their unique surface plasmon resonance (SPR) properties [8–10], noble metals commonly used are silver, gold, titanium and cooper for different application such as: antimicrobial agents, solar cells, 3D printing and biomedical applications, catalytic applications, among others [11–13]. Specifically, gold nanorods (Au NRs) of suitable dimensions and aspect ratio have the ability to absorb light in the near- infrared region of the electromagnetic spectrum (the so-called biolo- gical window), giving rise to a subsequent release of the adsorbed en- ergy through localized heat emission, which can be harnessed to be https://doi.org/10.1016/j.msec.2018.06.002 Received 1 August 2017; Received in revised form 22 March 2018; Accepted 6 June 2018 ⁎ Corresponding author. E-mail address: pablo.taboada@usc.es (P. Taboada). Materials Science & Engineering C 91 (2018) 669–678 0928-4931/ © 2018 Elsevier B.V. All rights reserved. T