ABSTRACT
We have proposed a new strategy for preparing free-standing nanofibrous webs from an inclusion complex (IC) of a well-known flavor/fragrance compound (limonene) with three modified cyclodextrins (HPßCD, MßCD, and HPγCD) via electrospinning (CD/limonene-IC-NFs) without using a polymeric matrix. The experimental and computational modeling studies proved that the stoichiometry of the complexes was 1:1 for CD/limonene systems. MßCD/limonene-IC-NF released much more limonene at 37, 50, and 75 °C than HPßCD/limonene-IC-NF and HPγCD/limonene-IC-NF because of the greater amount of preserved limonene. Moreover, MßCD/limonene-IC-NF has released only 25% (w/w) of its limonene, whereas HPßCD/limonene-IC-NF and HPγCD/limonene-IC-NF released 51 and 88% (w/w) of their limonene in 100 days, respectively. CD/limonene-IC-NFs exhibited high antibacterial activity against E. coli and S. aureus. The water solubility of limonene increased significantly and CD/limonene-IC-NFs were dissolved in water in a few seconds. In brief, CD/limonene-IC-NFs with fast-dissolving character enhanced the thermal stability and prolonged the shelf life along with antibacterial properties could be quite applicable in food and oral care applications.
Subject(s)
Anti-Bacterial Agents/chemistry , Cyclodextrins/chemistry , Cyclohexenes/chemistry , Drug Carriers/chemistry , Nanofibers/chemistry , Terpenes/chemistry , Computers, Molecular , Crystallography, X-Ray , Drug Liberation , Drug Stability , Escherichia coli/drug effects , Limonene , Magnetic Resonance Spectroscopy , Microscopy, Electron, Scanning , Oils, Volatile/chemistry , Particle Size , Solubility , Staphylococcus aureus/drug effects , ThermogravimetryABSTRACT
Cyclodextrin-inclusion complexes (CD-ICs) possess great prominence in food and pharmaceutical industries due to their enhanced ability for stabilization of active compounds during processing, storage and usage. Here, CD-IC of gallic acid (GA) with hydroxypropyl-beta-cyclodextrin (GA/HPßCD-IC) was prepared and then incorporated into polylactic acid (PLA) nanofibers (PLA/GA/HPßCD-IC-NF) using electrospinning technique to observe the effect of CD-ICs in the release behavior of GA into three different mediums (water, 10% ethanol and 95% ethanol). The GA incorporated PLA nanofibers (PLA/GA-NFs) were served as control. Phase solubility studies showed an enhanced solubility of GA with increasing amount of HPßCD. The detailed characterization techniques (XRD, TGA and (1)H-NMR) confirmed the formation of inclusion complex between GA and HPßCD. Computational modeling studies indicated that the GA made an efficient complex with HPßCD at 1:1 either in vacuum or aqueous system. SEM images revealed the bead-free and uniform morphology of PLA/GA/HPßCD-IC-NF. The release studies of GA from PLA/GA/HPßCD-IC-NF and PLA/GA-NF were carried out in water, 10% ethanol and 95% ethanol, and the findings revealed that PLA/GA/HPßCD-IC-NF has released much more amount of GA in water and 10% ethanol system when compared to PLA/GA-NF. In addition, GA was released slowly from PLA/GA/HPßCD-IC-NF into 95% ethanol when compared to PLA/GA-NF. It was also observed that electrospinning process had no negative effect on the antioxidant activity of GA when GA was incorporated in PLA nanofibers.
Subject(s)
Gallic Acid/chemistry , Nanofibers/chemistry , Polyesters/chemistry , beta-Cyclodextrins/chemistry , 2-Hydroxypropyl-beta-cyclodextrin , Antioxidants/chemistry , Antioxidants/metabolism , Microscopy, Electron, Scanning , Solubility , Thermogravimetry , Water/chemistry , X-Ray DiffractionABSTRACT
Electrospinning of polyacrylic acid (PAA) nanofibres (NF) incorporating ß-cyclodextrin inclusion complex (ß-CD-IC) of quercetin (QU) was performed. Here, ß-CD was used as not only the crosslinking agent for PAA nanofibres but also as a host molecule for inclusion of QU. The phase solubility test showed enhanced solubility of QU due to the inclusion complexation; in addition, the stoichiometry of QU/ß-CD-IC was determined to be 1:1. Computational modelling studies confirmed that 1:1 and 1:2 complex formation are desirable; 1:1 complex formation was chosen to have higher weight loading of QU. SEM images showed that PAA/QU/ß-CD-IC-NF were bead-free and uniform. XRD indicated that PAA/QU/ß-CD-IC-NF were amorphous in nature without the crystalline peaks of QU. Comparative results revealed that the release profile of QU from PAA/QU/ß-CD-IC-NF was much slower but greater in total than from PAA/QU/ß-CD-IC-film. Moreover, high antioxidant activity and photostability of QU was achieved in PAA/QU/ß-CD-IC-NF.
