Preparation, characterization, and antibacterial activity of diclofenac-loaded chitosan nanoparticles

Fulwah Yahya Alqahtani; Fadilah Sfouq Aleanizy; Eram El Tahir; Bushra T Alquadeib; Ibrahim A Alsarra; Jouri S Alanazi; Hosam Gharib Abdelhady

doi:10.1016/j.jsps.2018.08.001

Preparation, characterization, and antibacterial activity of diclofenac-loaded chitosan nanoparticles

Saudi Pharm J. 2019 Jan;27(1):82-87. doi: 10.1016/j.jsps.2018.08.001. Epub 2018 Aug 29.

Authors

Fulwah Yahya Alqahtani¹, Fadilah Sfouq Aleanizy¹, Eram El Tahir¹, Bushra T Alquadeib¹, Ibrahim A Alsarra¹, Jouri S Alanazi², Hosam Gharib Abdelhady³

Affiliations

¹ Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
² Pharmaceutical Care Department, National Guard Health Affairs, Riyadh, Saudi Arabia.
³ Biophysics and Surface Analysis, College of Pharmacy, Taibah University, Almadinah Almunawarrah, Saudi Arabia.

Abstract

Emerging antibiotic resistance necessitates the development of new therapeutic approaches. Many studies have reported the antimicrobial activity of diclofenac sodium (DIC) and chitosan nanoparticles (CNPs). Hence, this study aimed to prepare non-antibiotic DIC-loaded CNPs (DIC.CNPs) and characterize their in vitro antibacterial activity. DIC.CNPs were prepared from low and high molecular weight (LMW and HMW, respectively) chitosan using an ionic gelation method. Prepared NPs were characterized, and their antibacterial activity against gram-positive Staphylococcus aureus and Bacillus subtilis was evaluated using the agar diffusion and broth dilution methods. The particle size, polydispersity index (PDI), and encapsulation efficiency of the formulated DIC.CNPs increased with increasing MW of chitosan. The prepared NPs showed a narrow size distribution with low PDI values (0.18 and 0.24) and encapsulation efficiency (29.3% and 31.1%) for LMW.DIC.CNPs and HMW.DIC.CNPs, respectively. The in vitro release profile of DIC from the DIC.CNPs was biphasic with a burst release followed by slow release and was influenced by the MW of chitosan. DIC.CNPs exhibited significantly higher antibacterial activity against S. aureus (minimum inhibitory concentration [MIC₉₀] _LMW.DIC.CNPs = 35 µg/mL and MIC_{90 HMW.DIC.CNPs} = 18 µg/mL) and B. subtilis (MIC_{90 LMW.DIC.CNPs} = 17.5 µg/mL and MIC_{90 HMW.DIC.CNPs} = 9 µg/mL) than DIC alone did (MIC_{90 DIC} = 250 and 50 µg/mL against S. aureus and B. subtilis, respectively). The antibacterial activity was influenced by pH and the MW of chitosan. Collectively, these results may suggest the potential usefulness of DIC.CNPs as non-antibiotic antibacterial agent necessitating further future studies to asses the stability of DIC.CNPs prepared.

Keywords: Antimicrobial; Chitosan nanoparticles; DIC, diclofenac; DIC.CNPs, diclofenac-loaded chitosan nanoparticles; HMW, high-molecular weight; High-molecular weight chitosan; LMW, low-molecular weight; Low-molecular weight chitosan; Non-antibiotic.