Synthesis, characterization and drug release activity of poly(ε-caprolactone)/Fe₃O₄–alizarinred nanocomposites

Abstract

Applications of magnetic and fluorescent poly(ε-caprolactone) (PCL) is increased rapidly in the biomedical engineering field as a bioimaging probe. This urged us to do the present work. In the present investigation, the role of Fe 3 O 4-AR dye nanohybrid on the ring opening polymerization (ROP) of CL was studied at different experimental conditions such as variation in [M] and [M/I]. Prior to ROP of CL, the nanohybrid was characterized by various spectral methods like FTIR spectroscopy, UV-visible spectroscopy, fluorescence spectroscopy, VSM and FESEM like analytical techniques. The Fe 3 O 4-AR nanohybrid is used as an initiator for the ROP of CL. After the formation of PCL/Fe 3 O 4-AR nanocomposite again the systems were characterized by FTIR spectroscopy, UV-visible spectroscopy, fluorescence spectroscopy, DSC, VSM and FESEM like methods. The interesting point noted in the present investigation is the size of Fe 3 O 4 nanoparticle was found to be reduced after the nanohybrid and nanocomposite formation. The three functional groups of AR dye were involved in the ROP of CL. The binding constant and number of binding sites were determined.

Low temperature splinting activity and catalytic behavior of nano Ag doped sulphamicacid bridged diblock copolymer

“…Figure A indicates the 1 H‐NMR spectrum of SA‐PCL system. The alkoxy proton appeared around 4.02 ppm whereas the ester ―CH 2 proton appeared at 2.42 ppm . The remaining signals were matched with the structure of PCL.…”

“…The ―CH symmetry and anti‐symmetry stretching of PCL is seen at 2863 and 2943 cm −1 , respectively. The C═O stretching of PCL appeared at 1717 cm −1 . Here, the C═O stretching is blue shifted due to the presence of ―SO 3 H group in SA.…”

“…Figure B indicates the 13 C‐NMR spectrum of SA‐PCL system. Here the carbonyl carbon signal was observed at 173 ppm . The ―OCH 2 carbon signal appeared around 63 ppm.…”

“…The TGA thermogram of homo PCL is given in Figure D with a 2‐step degradation process. The first major weight loss around 380°C is due to the degradation of PCL backbone . The second minor weight loss at 470°C is due to the degradation of SA group.…”

“…The DSC thermogram of SA‐PCL system is given in Figure A. The thermogram exhibits an endothermic peak at 75.7°C corresponding to the T m of PCL . The low T m value of PCL increased its application in bio‐medical engineering field as a splinting material.…”