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Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

ABSTRACT: Tunable and durable photochromic materials are a rapidly expanding area of interest, with applications ranging from biomedical devices to industrial-fields. Here we examine electrospun poly (methacrylic acid) PMAA nanofibers covalently modified with the highly photochromic molecule, spiropyran (SP) or a derivate SP which is firstly coupled to a cyclodextrin molecule (?CDSP). The photochromic properties of the starting materials and of the nanofibers were investigated. ?CDSP, PMAASP and PMAA-?CDSP polymers exhibited a reverse photochromism. The kinetic results revealed a faster isomerization process for the ?CDSP molecule, than that for the PMAA-?CDSP and for the PMAASP, the slowest one. The fastest isomerization is attributed to the presence of a large number of hydroxyl groups of the ?CD which stabilizes the merocyanine form via hydrogen bonding, and the slowest isomerization is related to the PMAA chain structure that stabilizes the spiropyran form. Thus, combining the PMAA and ?CD properties the photo-isomerization can be modulated. The photoreversibility of this material was verified by UV-visible measurements cycling visible and UV light. Infrared spectroscopy and water contact angle were used for the nanofiber surface characterization, demonstrating the presence of the spiropyran on the mats surface and also showing a minimal effect on nanofiber size and shape when compared to PMAA fiber.

SUBMITTER: De Sousa FB

PROVIDER: S-EPMC5307972 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

De Sousa Frederico B FB Guerreiro João D T JD Ma Minglin M Anderson Daniel G DG Drum Chester L CL Sinisterra Rubén D RD Langer Robert R

Journal of materials chemistry 20100928 44

Tunable and durable photochromic materials are a rapidly expanding area of interest, with applications ranging from biomedical devices to industrial-fields. Here we examine electrospun poly (methacrylic acid) PMAA nanofibers covalently modified with the highly photochromic molecule, spiropyran (SP) or a derivate SP which is firstly coupled to a cyclodextrin molecule (βCD<sub>SP</sub>). The photochromic properties of the starting materials and of the nanofibers were investigated. βCD<sub>SP</sub> ...[more]

PMID: 28210069

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Project description:The electrospinning of hydrocortisone/cyclodextrin complex nanofibers was performed in order to develop a fast-dissolving oral drug delivery system. Hydrocortisone is a water-insoluble hydrophobic drug, yet, the water solubility of hydrocortisone was significantly enhanced by inclusion complexation with hydroxypropyl-beta-cyclodextrin (HP-β-CyD). In this study, hydrocortisone/HP-β-CyD complexes were prepared in aqueous solutions having molar ratios of 1/1, 1/1.5 and 1/2 (hydrocortisone/HP-β-CyD). Highly concentrated aqueous solutions of HP-β-CyD (180%, w/v) were used for hydrocortisone/HP-β-CyD systems (1/1, 1/1.5 and 1/2) in order to perform electrospinning without the use of an additional polymer matrix. The turbidity of hydrocortisone/HP-β-CyD (1/1 and 1/1.5) aqueous solutions indicated the presence of some uncomplexed crystals of hydrocortisone whereas the aqueous solution of hydrocortisone/HP-β-CyD (1/2) was homogeneous indicating that hydrocortisone becomes totally water-soluble by inclusion complexation with HP-β-CyD. Nonetheless, the electrospinning of hydrocortisone/HP-β-CyD systems (1/1, 1/1.5 and 1/2) successfully yielded defect-free uniform nanofibrous structures. Moreover, the electrospinning process was quite efficient that hydrocortisone was completely preserved without any loss yielding hydrocortisone/HP-β-CyD nanofibers having the initial molar ratios (1/1, 1/1.5 and 1/2). The structural and thermal characterization of the hydrocortisone/HP-β-CyD nanofibers revealed that hydrocortisone was totally inclusion complexed with HP-β-CyD and was in the amorphous state in hydrocortisone/HP-β-CyD (1/2) nanofibers whereas some uncomplexed crystalline hydrocortisone was present in hydrocortisone/HP-β-CyD (1/1 and 1/1.5) nanofibers. Nevertheless, hydrocortisone/HP-β-CyD (1/1, 1/1.5 and 1/2) complex aqueous systems were electrospun in the form of nanofibrous webs having a free-standing and flexible nature. The hydrocortisone/HP-β-CyD (1/1, 1/1.5 and 1/2) nanofibrous webs have shown fast-dissolving behavior in water or when they were in contact with artificial saliva. Yet, the hydrocortisone/HP-β-CyD (1/2) nanofibrous web dissolved more quickly than the hydrocortisone/HP-β-CyD (1/1 and 1/1.5) nanofibrous webs due to the full inclusion complexation and the amorphous state of hydrocortisone in this sample. In short, the results suggest that polymer-free electrospun nanofibrous webs produced from hydrocortisone/HP-β-CyD could be quite applicable for fast-dissolving oral drug delivery systems.

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Dataset Information

Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

Publications

Photo-response behavior of electrospun nanofibers based on spiropyran-cyclodextrin modified polymer.

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