Electrospun crosslinked poly-cyclodextrin nanofibers: Highly efficient molecular filtration thru host-guest inclusion complexation

Water pollution is a serious concern for public health and environment in today's world; hence, there exists a strong demand to develop cost-effective, sustainable and eco-friendly membranes. Here, we produce a highly efficient molecular filter membrane based on bio-renewable material; cyclic oligosaccaharides known as cyclodextrins (CD). Crosslinked insoluble poly-CD nanofibers are produced by using electrospinning technique in the absence of any additional polymeric carrier. Poly-CD nanofibrous membrane exhibit significant affinity to a common class of organic pollutant (i.e. methylene blue (MB)). Remarkably, the electrospun poly-CD nanofibrous web can outdistance the commonly used filter material (i.e. activated carbon) in terms of removal capacity. The flexible and free-standing poly-CD nanofibrous membrane depicted outstanding filtration performance. We estimate of above 90% removal efficiency for highly concentrated solutions of MB pollutant (40 mg/L) under extremely high flux (3840 Lm-2h-1). Essentially, these poly-CD nanofibrous webs demonstrate quite rapid uptake of MB from liquid environment. Overall, bio-based flexible electrospun poly-CD nanofibrous membrane represents a highly efficient molecular filter for wastewater treatment. © 2017 The Author(s)

Polymer-free electrospun nanofibers from sulfobutyl ether7-beta-cyclodextrin (SBE7-β-CD) inclusion complex with sulfisoxazole: Fast-dissolving and enhanced water-solubility of sulfisoxazole

In this study, our aim was to develop solid drug-cyclodextrin inclusion complex system having nanofibrous morphology in order to have fast-dissolving property and enhanced water-solubility of poorly water-soluble drug. Here, we prepared a highly concentrated aqueous solution of inclusion complex between sulfisoxazole and sulfobutyl ether7-beta-cyclodextrin (SBE7-β-CD, Captisol®), and then, without using any polymeric matrix, the electrospinning of sulfisoxazole/SBE7-β-CD-IC nanofibers was performed in order to obtain free-standing and handy nanofibrous web. As a control sample, nanofibers from pure SBE7-β-CD was also electrospun and free-standing nanofibrous web was obtained. The SEM imaging revealed that the bead-free and uniform nanofiber morphology with the average fiber diameter (AFD) of 650 ± 290 nm for sulfisoxazole/SBE7-β-CD-IC NF and 890 ± 415 nm for pure SBE7-β-CD NF was obtained. The inclusion complex formation between sulfisoxazole and SBE7-β-CD in sulfisoxazole/SBE7-β-CD-IC NF sample was confirmed by 1H NMR, TGA, DSC, XRD and FTIR analyses. Due to the combined advantage of cyclodextrin inclusion complexation and high surface area of electrospun nanofibers, fast-dissolving property with enhanced water-solubility was successfully achieved for sulfisoxazole/SBE7-β-CD-IC NF. Our findings suggest that electrospun nanofibers/nanowebs from CD-IC of poorly water-soluble drugs may offer applicable approaches for high water-solubility and fast-dissolving tablet formulations for drug delivery systems. © 2017 Elsevier B.V

Wpływ rodności na kształt fali przepływu Dopplera w pierwszym trymestrze pojedynczej ciąży niskiego ryzyka

Objectives: The aim of the study was to evaluate the effect of parity on uteroplacental blood flow during the first trimester in low-risk singleton pregnancies. Materials and methods: Uterine artery Doppler examinations were performed in 190 singleton pregnancies between 11-14 gestational weeks. Twenty-five pregnancies were excluded from the study due to history of preeclampsia, diabetes mellitus or inherited thrombophilia. A total of 165 low-risk singleton pregnancies were included in the study. Mean uterine artery pulsatility index (PI) was recorded and compared between nulliparous and multiparous women. The relation between maternal age, gestational week, maternal weight, parity, biochemical markers and abnormal uterine artery Doppler flows was evaluated. T-test and logistic regression analyses were used for the statistical analysis. Results: A total of 165 singleton pregnancies without any risk factors for uteroplacental insufficiency were included in the study. Of them, 58 (36.7%) were nulliparous and 107 (63.3%) were parous. Correlation analysis revealed that the uterine artery pulsatility indices during the first trimester were not affected by maternal age and parity. Conclusions: Mean uterine artery pulsatility indices are not different in nulliparous and multiparous low risk pregnancies at 11-14 weeks of gestation.Cel: Celem badania była ocena wpływu rodności na przepływ maciczno-łożyskowy w pierwszym trymestrze pojedynczej ciąży niskiego ryzyka. Materiał i metoda: Przepływ w tętnicy macicznej zbadano w 190 pojedynczych ciążach w 11-14 tygodniu. Z analizy wyłączono 25 ciąż z powodu dodatniego wywiadu w kierunku stanu przedrzucawkowego, cukrzycy lub wrodzonej trombofilii. Ostatecznie do badania włączono 165 pojedynczych ciąż niskiego ryzyka. Zmierzono średni indeks pulsacji w tętnicy macicznej (PI), który porównano pomiędzy nieródkami i wieloródkami. Oceniono również związek pomiędzy wiekiem matki, wiekiem ciążowym, masą matki, liczbą porodów, markerami biochemicznymi a nieprawidłowym przepływem w tętnicach macicznych. T-test i regresji logistycznej zostały wykorzystane do analizy statystycznej. Wyniki: Do badania włączono 165 pojedynczych ciąż bez czynników ryzyka niewydolności maciczno-łożyskowej. Z tej grupy, 58 (36,7%) kobiet było nieródkami a 107 (63,3%) wieloródkami. Analiza statystyczna wykazała brak związku pomiędzy indeksem pulsacji w pierwszym trymestrze ciąży a wiekiem matki i rodnością. Wnioski: Średni indeks pulsacji w tętnicy macicznej nie różni się pomiędzy nieródkami a wieloródkami w ciąży niskiego ryzyka w 11-14 tygodniu

Electrospinning of cyclodextrin/linalool-inclusion complex nanofibers: Fast-dissolving nanofibrous web with prolonged release and antibacterial activity

The volatility and limited water solubility of linalool is a critical issue to be solved. Here, we demonstrated the electrospinning of polymer-free nanofibrous webs of cyclodextrin/linalool-inclusion complex (CD/linalool-IC-NFs). Three types of modified cyclodextrin (HPβCD, MβCD, and HPγCD) were used to electrospin CD/linalool-IC-NFs. Free-standing CD/linalool-IC-NFs facilitate maximum loading of linalool up to 12% (w/w). A significant amount of linalool (45–89%) was preserved in CD/linalool-IC-NFs, due to enhancement in the thermal stability of linalool by cyclodextrin inclusion complexation. Remarkably, CD/linalool-IC-NFs have shown fast-dissolving characteristics in which these nanofibrous webs dissolved in water within two seconds. Furthermore, linalool release from CD/linalool-IC-NFs inhibited growth of model Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria to a great extent. Briefly, characteristics of liquid linalool have been preserved in a solid nanofiber form and designed CD/linalool-IC-NFs confer high loading capacity, enhanced shelf life and strong antibacterial activity of linalool. © 2017 Elsevier Lt

Fast-Dissolving, Prolonged Release, and Antibacterial Cyclodextrin/Limonene-Inclusion Complex Nanofibrous Webs via Polymer-Free Electrospinning

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 (HPβCD, MβCD, 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. MβCD/limonene-IC-NF released much more limonene at 37, 50, and 75 °C than HPβCD/limonene-IC-NF and HPγCD/limonene-IC-NF because of the greater amount of preserved limonene. Moreover, MβCD/limonene-IC-NF has released only 25% (w/w) of its limonene, whereas HPβCD/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. © 2016 American Chemical Society

Recent trends and developments in pyrolysis-gas chromatography: review

Pyrolysis-gas chromatography (Py-GC) has become well established as a simple, quick and reliable analytical technique for a range of applications including the analysis of polymeric materials. Recent developments in Py-GC technology and instrumentation include laser pyrolysis and non-discriminating pyrolysis. Progress has also been made in the detection of low level polymer additives with the use of novel Py-GC devices. Furthermore, it has been predicted that future advances in separation technology such as the use of comprehensive two-dimensional gas chromatography will further enhance the analytical scope of Py-GC

Efficient Removal of Polycyclic Aromatic Hydrocarbons and Heavy Metals from Water by Electrospun Nanofibrous Polycyclodextrin Membranes

Here, a highly efficient membrane based on electrospun polycyclodextrin (poly-CD) nanofibers was prepared and exploited for the scavenging of various polycyclic aromatic hydrocarbons (PAHs) and heavy metals from water. The poly-CD nanofibers were produced by the electrospinning of CD molecules in the presence of a cross-linker (i.e., 1,2,3,4-butanetetracarboxylic acid), followed by heat treatment to obtain an insoluble poly-CD nanofibrous membrane. The membrane was used for the removal of several PAH compounds (i.e., acenaphthene, fluorene, fluoranthene, phenanthrene, and pyrene) and heavy metals (i.e., Pb2+, Ni2+, Mn2+, Cd2+, Zn2+, and Cu2+) from water over time. Experiments were made on the batch sorption of PAHs and heavy metals from contaminated water to explore the binding affinity of PAHs and heavy metals to the poly-CD membrane. The equilibrium sorption capacity (qe) of the poly-CD nanofibrous membrane was found to be 0.43 ± 0.045 mg/g for PAHs and 4.54 ± 0.063 mg/g for heavy metals, and the sorption kinetics fitted well with the pseudo-second-order model for both types of pollutants. The membrane could be recycled after treatment with acetonitrile or a 2% nitric acid solution and reused up to four times with similar performance. Further, dead-end filtration experiments showed that the PAH removal efficiencies were as high as 92.6 ± 1.6 and 89.9 ± 4.8% in 40 s for the solutions of 400 and 600 μg/L PAHs, respectively. On the other hand, the removal efficiencies for heavy metals during the filtration were 94.3 ± 5.3 and 72.4 ± 23.4% for 10 and 50 mg/L solutions, respectively, suggesting rapid and efficient filtration of heavy metals and PAHs by the nanofibrous poly-CD membrane

Efficient Encapsulation of Citral in Fast-Dissolving Polymer-Free Electrospun Nanofibers of Cyclodextrin Inclusion Complexes: High Thermal Stability, Longer Shelf-Life, and Enhanced Water Solubility of Citral

Here, we report a facile production of citral/cyclodextrin (CD) inclusion complex (IC) nanofibers (NFs) from three types of CDs (hydroxypropyl-beta-cyclodextrin (HPβCD), hydroxypropyl-gamma-cyclodextrin (HPγCD), and methylated-beta-cyclodextrin (MβCD)) by an electrospinning technique without the need of any polymeric carrier matrix. Self-standing nanofibrous webs of citral/CD-IC nanofibers (citral/CD-IC-NF) with uniform fiber morphology have been successfully electrospun from aqueous solutions of citral/CD-IC. Thanks to the inclusion complex formed with CDs, the efficient preservation of citral (up to ~80%) in citral/CD-IC-NFs was observed. In addition, the citral/CD-IC-NFs have shown ~50% preservation of citral for 15 days at room temperature even though citral has a highly volatile nature. The enhanced thermal stability of citral (~100–300°C) in citral/CD-IC-NFs compared to pure citral (~50–165°C) has been observed. Moreover, citral/CD-IC-NFs tended to disintegrate in water very quickly. To summarize, citral was efficiently encapsulated in citral/CD-IC-NFs, and these citral/CD-IC-NFs have been shown to be fast dissolving. In citral/CD-IC-NFs, citral/CD-ICs have enhanced water solubility of citral along with high-temperature stability and a longer shelf-life