Theranostic Fibers for Simultaneous Imaging and Drug Delivery.
New methods for creating theranostic systems with simultaneous encapsulation of therapeutic, diagnostic, and targeting agents are much sought after. This work reports for the first time the use of coaxial electrospinning to prepare such systems in the form of core-shell fibers. Eudragit S100 was used to form the shell of the fibers, while the core comprised poly(ethylene oxide) loaded with the magnetic resonance contrast agent Gd(DTPA) (Gd(III) diethylenetriaminepentaacetate hydrate) and indomethacin as a model therapeutic agent. The fibers had linear cylindrical morphologies with clear core-shell structures, as demonstrated by electron microscopy. X-ray diffraction and differential scanning calorimetry proved that both indomethacin and Gd(DTPA) were present in the fibers in the amorphous physical form. This is thought to be a result of intermolecular interactions between the different components, the presence of which was suggested by infrared spectroscopy. In vitro dissolution tests indicated that the fibers could provide targeted release of the active ingredients through a combined mechanism of erosion and diffusion. The proton relaxivities for Gd(DTPA) released from the fibers into tris buffer increased (r1 = 4.79-9.75 s(-1) mM(-1); r2 = 7.98-14.22 s(-1) mM(-1)) compared with fresh Gd(DTPA) (r1 = 4.13 s(-1) mM(-1) and r2 = 4.40 s(-1) mM(-1)), which proved that electrospinning has not diminished the contrast properties of the complex. The new systems reported herein thus offer a new platform for delivering therapeutic and imaging agents simultaneously to the colon.
UCL School of Pharmacy, University College London , 29-39 Brunswick Square, London WC1N 1AX, U.K.
Miao
M
Jin
School of Materials Science & Engineering, University of Shanghai for Science and Technology , Shanghai 200093, China.
Deng-Guang
DG
Yu
Department of Life Sciences and Coimbra Chemistry Center - CQC, Faculty of Science and Technology, University of Coimbra , 3000-393 Coimbra, Portugal.
Carlos F G C
CF
Geraldes
UCL School of Pharmacy, University College London , 29-39 Brunswick Square, London WC1N 1AX, U.K.
Gareth R
GR
Williams
Department of Life Sciences, Faculty of Science and Technology, University of Westminster , 115 New Cavendish Street, London W1W 6UW, U.K.
S W Annie
SW
Bligh
D002152:Calorimetry, Differential Scanning; D003287:Contrast Media / Q000138:chemical synthesis / Q000737:chemistry*; D003952:Diagnostic Imaging / Q000379:methods*; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods*; D019786:Gadolinium DTPA / Q000737:chemistry; D007811:Lanthanum / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D017550:Spectroscopy, Fourier Transform Infrared; D000068936:Theranostic Nanomedicine / Q000379:methods*; D014961:X-Ray Diffraction
D003287:Contrast Media; D004337:Drug Carriers; D007811:Lanthanum; D019786:Gadolinium DTPA
coaxial electrospinning; core−shell fibers; image-guided drug delivery; multifunctionality; theranostics