Nanomaterial-based drug-delivery system as an aid to antimicrobial photodynamic therapy in treating oral biofilm
Creators: name: Sun, Guanwen
name: Huang, Shan
name: Wang, Shaofeng
name: Li, Yijun
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Space Science
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Biotechnology
subject: Chemical Sciences not elsewhere classified
subject: Astronomical and Space Sciences not elsewhere classified
subject: Biological Sciences not elsewhere classified
subject: Infectious Diseases
subject: FOS: Health sciences

description: Diverse microorganisms live as biofilm in the mouth accounts for oral diseases and treatment failure. For decades, the prevention and treatment of oral biofilm is a global challenge. Antimicrobial photodynamic therapy (aPDT) holds promise for oral biofilm elimination due to its several traits, including broad-spectrum antimicrobial capacity, lower possibility of resistance and low cytotoxicity. However, the physicochemical properties of photosensitizers and the biological barrier of oral biofilm have limited the efficiency of aPDT. Nanomaterials has been used to fabricate nanocarriers to improve photosensitizer properties and thus enhance antimicrobial effect. In this review, we have discussed the challenges of aPDT used in dentistry, categorized the nanomaterial-delivery system and listed the possible mechanisms involved in nanomaterials when enhancing aPDT effect. aPDT has been advocated as a promising alternative approach against oral biofilm, with the advantages of multiple targets, low possibility of resistance development, and minimal cytotoxicity to host cells. Oral biofilm harbors several important traits that make them difficult to amend, including abundant EPS matrix, quorum-sensing systems, multi-species interaction and resistance to drugs. The extraordinary locations of the oral cavity such as the lateral canal, deep periodontal pocket, root furcation and screwed-implant surface are not easily accessible for external interventions. aPDT is characterized as a procedure that involves the photochemical reaction of PS, light source and oxygen, which ultimately generates ROS. PSs can be categorized into porphyrin dyes, chlorophyll dyes, phthalocyanine dyes, phenothiazinium dyes, xanthene dyes, curcumin and phenalenone dyes. These current PS are hydrophobic and tend to aggregate in an aqueous solution, leading to poor bioavailability and fluorescence quenching. The versatile features of nanomaterials, such as ultra-small size, large surface area, and highly reactive surface, could be utilized as drug-delivery systems to modify PS properties and improve aPDT effect. The encapsulation or incorporation of PS into nanomaterials has achieved several improvements, such as improved bioavailability and solubility of PS, enhanced increase of ROS yield, targeting of infection sites, improved therapeutic action of PS and so on. There are several possible mechanisms involved in nanomaterials enhancing aPDT effect, including increase of microbial cell membrane permeability, disruption of EPS formation, increase of ROS quantum yield and increase of PS's penetration depth. Despite a number of studies reporting positive results of nanomaterials-based PSs, there is a great deal of work needs to be undertaken in order to overcome the limitations and challenges of nanomaterials as a drug-delivery system for PS.