Synthesis of photo-excited Chlorin e6 conjugated silica nanoparticles for enhanced anti-bacterial efficiency to overcome methicillin-resistant Staphylococcus aureus

Abstract

Nano photodynamic therapy to overcome multidrug resistant bacteria.

<p>Novel nanomaterial-based antibacterial photodynamic therapies to combat oral bacterial biofilms and infectious diseases</p>

“…Recently, Lin et al synthesized Ce6 loaded SiNPs with greater efficacy in inhibiting S. aureus and MRSA. The photostability of Ce6 molecules was significantly improved and maintained the 1 O 2 generation capacity upon light illumination 76…”

Phototherapy-based combination strategies for bacterial infection treatment

“…Therefore, the prepared small molecule photosensitizer-loaded nanoparticles, which can respond to the microenvironment of bacterial infected tissues, are the best choices to improve the phototherapy efficacy and helpful to slow down the emergence of side effects. For example, Yan et al 24 synthesized silica nanoparticles doped with Ce6. This hybrid structure exhibits enhanced photostability and a high antibacterial efficiency towards Staphylococcus aureus ( S. aureus ) and methicillin-resistant S. aureus (MRSA).…”

Selective Photoinactivation of Methicillin‐Resistant Staphylococcus aureus by Highly Positively Charged RuII Complexes

“…ROS, mainly singlet oxygen ( 1 O 2 ), are highly reactive and can damage DNA, proteins, and lipids effectively . The multi‐target feature of ROS not only renders aPDT highly potent in killing even multidrug resistant bacteria, but also makes bacteria difficult to develop any resistance against these multiple attacks …”

“…[8] The multi-target feature of ROS not only renders aPDT highlyp otent in killing even multidrug resistantb acteria, but also makes bacteria difficult to develop any resistance against these multiplea ttacks. [9][10][11] However,t he same modes of action of PDT and aPDT raise a great challenge in selectively inactivating bacterialc ells but leavingm ammalian cells unaffected.U nlike mammalian cells, in whicha cidic phospholipidsa re mainly located in the inner leafleto fp lasma membranes, acidic phospholipids andn egatively chargedc omponents, such as teichuronic acid (for Gram positive bacteria, for example, S. aureus)a nd lipopolysaccharide (for Gram negative bacteria, for example, E. coli)a re mainly locatedi nt he outer edges of cell walls or outer membranes, making the bacterial surface highly negatively charged. [12,13] This disparity has been leveraged to develop cationic aPDT agents, such as triarylmethanes [14,15] and borondipyrromethene (BODIPY)d yes bearing two positive charges, [16] peryleneb earing four positive charges, [17] porphyrins, [18][19][20][21][22][23] phthalocyanines [24] and bacteriochlorin [25,26] bearing three, four, or eight positive charges, with the aim to achieve higher binding affinity toward bacteria.T hough these photosensitizers showed remarkable inactivation capability against bacterial cells, in several cases, phototoxicity towardm ammalianc ells was observed, [14,23] suggestingl imited selectivity of the aPDT agents.…”