Remote-controlled delivery of CO via photoactive CO-releasing materials on a fiber optical device

Abstract

Although carbon monoxide (CO) delivery materials (CORMAs) have been generated, remote-controlled delivery with light-activated CORMAs at a local site has not been achieved. In this work, a fiber optic-based CO delivery system is described in which the photoactive and water insoluble CO releasing molecule (CORM) manganese(i) tricarbonyl [(OC)3Mn(μ3-SR)]4 (R = nPr, 1) has been non-covalently embedded into poly(l-lactide-co-d/l-lactide) and poly(methyl methacrylate) non-woven fabrics via the electrospinning technique. SEM images of the hybrid materials show a porous fiber morphology for both polymer supports. The polylactide non-woven fabric was attached to a fiber optical device. In combination with a laser irradiation source, remote-controlled and light-triggered CO release at 405 nm excitation wavelength was achieved. The device enabled a high flexibility of the spatially and timely defined application of CO with the biocompatible hybrid fabric in aqueous media. The rates of liberated CO were adjusted with the light intensity of the laser. CO release was confirmed via ATR-IR spectroscopy, a portable electrochemical CO sensor and a heterogeneous myoglobin assay.

Two‐Photon‐Induced CO‐Releasing Molecules as Molecular Logic Systems in Solution, Polymers, and Cells

“…The research groups of Motterlini, Mascharak, Ford, or Schatzschneider, for example, thoroughly investigated the use of CORMs and photoCORMs based on transition‐metal complexes . Most of these photoCORMs require UV or blue light for efficient CO release . Light in this region is not only toxic to cells and tissues, but its penetration length through human skin and tissues is limited .…”

“…Acetonitrile solutions of 1 or 2 were photolyzed with a two‐photon laser beam (800 nm, 50 mW cm −2 ) as described in Figure S17, Supporting Information. The amount of CO release was measured using a portable CO gas sensor (Drager Pac 7000) in a closed desiccator . From the graph shown in Figure S18, Supporting Information, one could observe that the nonbiotin conjugated photoCORM 1 released a higher amount of CO (220 ppm) than 2 (145 ppm), while none of the compounds released any CO in the dark.…”

“…Embedding photoCORMs into nonwoven materials represents one way to prevent the release of toxic metal fragments after CO release . Hence, 1 and 2 were embedded in poly( l ‐lactide‐co‐ d / l ‐lactide) (PLA) nonwoven fabric material by electrospinning techniques . The resulting materials were named as PLA‐1 and PLA‐2 .…”

Manganese(I)-Based CORMs with 5-Substituted 3-(2-Pyridyl)Pyrazole Ligands

“…In order to also demonstrate the suitability of these complexes, as a representative example the CO release of 2a was investigated at the solid phase. The amount of liberated CO was detected and quantified with a portable CO sensor (Dräger Pac7000, Drägerwerk AG &Co. KGaA, Lübeck, Germany) during illumination with LED lamps in a closed desiccator, as described elsewhere [26]. The measurements were performed with two different wavelengths (365 and 480 nm) and liberated CO was quantified as number of released CO molecules per CORM.…”

“…However, immobilized CORMs increasingly gain attention and diverse concepts exist to administer carbon monoxide from such insoluble CORMs [24,25]. As a representative example, insoluble CORMs can be embedded in matrices [3] such as non-wovens [26,27] and CO is released upon illumination whereas the degradation products remain in the polymer matrices and, hence, the hazard potential of metal-containing degradation products plays an insignificant role. For soluble CORMs, low toxicity is required for the CORMs as well as for their degradation end-products after CO release.…”