Visible‐Light‐Induced Disruption of Diselenide‐Containing Layer‐by‐Layer Films: Toward Combination of Chemotherapy and Photodynamic Therapy

Abstract

A photoresponsive polyelectrolyte multilayer film containing a diselenide functional group is fabricated using an unconventional layer-by-layer method. The polycation backbone is constructed through copolymerization of di-(1-hydroxylundecyl) diselenide and 1,4-bis(2-hydroxyethyl)piperazine with 2,4-diisocyanatotoluene. A common polyanion poly(styrene sulfonate) is selected as the polyanion. The obtained film can be gradually disrupted under the irradiation of mild visible light, and this process can be monitored with UV-vis spectroscopy. The residue of the film is estimated to be 17% after 5 h of irradiation. The intensity of the visible light can be as low as 50 mW cm⁻², which is even weaker than the sunlight. The cytotoxicity of the building blocks is evaluated in MTT assays using human hepatic cell line (L-02), and the results are satisfactory. Further tests show that cells can grow in a regular manner on this film, indicating good biocompatibility. In addition, the film can be used to achieve cargo loading and controlled release. Considering that light can not only trigger controlled release but also act as part of the therapy itself (photodynamic therapy), this system shows hope for further development into a platform for the combination of chemotherapy and photodynamic therapy, especially for applications concerning skin.

Nanocoating for biomolecule delivery using layer-by-layer self-assembly

“…Light is an attractive trigger for release due to its spatial and temporal precision and its ability to be applied remotely, rendering it noninvasive. 98 Visible light was shown to produce reactive oxygen species in vivo that can cleave diselenide bonds in a diselenide-containing polycation layered with a PSS polyanion, resulting in controlled release of 8-hydroxy-1,3,6-pyrenetrisulfonic acid, a fluorophore. 98 The application of near-infrared radiation successfully resulted in the controlled release of doxycycline from an Ag-nanocage surrounded by mesoporous SiO 2 and coated with PNIPAM, 99 and UV light triggered the aggregation of poly(diallyldimethylammonium chloride) (PDADMAC)/poly(1-[4-(3-carboxy-4-hydroxyphenylazo) benzenesulfonamido]-1,2-ethanediyl, sodium salt) (PAZO) polyelectrolytes for microcapsule breakage and the release of bovine serum albumin.…”

“…The visible light example relied on photochemical cleavage of polymer bonds to liberate the fluorophore trapped between layers. 98 In the near-infrared example, 99 light was used to elicit a thermal response that subsequently triggered biomolecule release. Heat was released upon light absorption by metal and metal-oxide nanoparticles and dyes.…”

Redox poly(ethylene glycol)-b-poly(l-lactide) micelles containing diselenide bonds for effective drug delivery

“…However, due to the drug resistance of cancer cells, nonspecific adsorption in circulation and so on, chemotherapy is usually accompanied by the serious side effects and low drug bioavailability [1][2][3]. In the past decades, stimuli-responsive amphiphilic polymers have attracted much attention in drug delivery, and a series of pH-, CO 2 À , temperature-and light-stimuli polymers have already been synthesized and realized the controlled release of the encapsulated drugs [4][5][6][7]. Among these, the redox drug delivery systems which are stimuli-response to glutathione (GSH) have been designed for tumor therapy because of the different GSH concentrations between tumor extracellular and intracellular environments [8].…”

A Biocompatible Multilayer Film from an Asymmetric Picolinium‐Containing Polycation with Fast Visible‐Light/NIR‐Degradability

“…Consequently, the loaded drugs or DNA are released, and defect‐free films are also delaminated from substrates . A diselenide‐containing LbL film is disrupted with visible light irradiation, and the degradation process is helpful for not only cargo‐controlled release, but also the chemotherapy and photodynamic therapy . It is worthy of note that visible light and NIR have the merits of harmlessness to the human body and the capability of deeply penetrating into tissues, thus surpassing the limitations imposed by UV light.…”