PREPARATION AND CHARACTERIZATION OF TRIFLUOPERAZINE LOADED TRANSDERMAL PATCHES FOR SUSTAINED RELEASE

Objective: The purpose of the present study was to formulate and evaluate the polymeric transdermal delivery system of antipsychotic drug Trifluoperazine (TFP) for sustained drug release. Methods: A transdermal patch loaded with (TFP) was formulated by solvent casting technique. Polyvinyl pyrrolidone (PVP) K-30 and ethyl cellulose (EC) was used as a polymeric matrix with different ratios. Di n-butyl phthalate was used as a plasticizer. The parameters such as thickness, folding endurance and weight variation of the prepared patches were studied. The interaction study by attenuated total reflectance-infrared (ATR-IR) spectroscopy, X-ray diffraction and thermal analysis by differential scanning calorimetry (DSC) were performed. In vitro drug release study was performed by modified paddle over-disc technique. Results: The infrared spectroscopic study confirmed the absence of any chemical interaction between TFP and selected polymers. All the prepared formulations showed folding endurance values ranging from 130-162 and a satisfactory drug loading of 90-95%. In in vitro drug release study, formulations PE-3 and PE-4 exhibited a sustained and stable cumulative release of 54 % and 48% respectively, at the end of 24 h. The DSC and XRD analysis proved the partial conversion of the drug from crystalline to amorphous form when integrated into the polymeric matrix. Conclusion: The prepared transdermal formulations using polymers PVP and ethyl cellulose demonstrated their ability to sustain the release of TFP. The developed formulation could be exploited for multiday therapy of TFP for the effective treatment of schizophrenia with a simplified dosing regimen and enhanced patient compliance.

Pressure-Dependent Clustering in Ionic-Liquid-Poly (Vinylidene Fluoride) Mixtures: An Infrared Spectroscopic Study

The nanostructures of ionic liquids (ILs) have been the focus of considerable research attention in recent years. Nevertheless, the nanoscale structures of ILs in the presence of polymers have not been described in detail at present. In this study, nanostructures of ILs disturbed by poly(vinylidene fluoride) (PVdF) were investigated via high-pressure infrared spectra. For 1-(2-hydroxyethyl)-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([HEMIm][TFSI])-PVdF mixtures, non-monotonic frequency shifts of the C4,5-H vibrations upon dilution were observed under ambient pressure. The experimental results suggest the presence of microheterogeneity in the [HEMIm][TFSI] systems. Upon compression, PVdF further influenced the local structure of C4,5–H via pressure-enhanced IL–PVdF interactions; however, the local structures of C2–H and hydrogen-bonded O–H were not affected by PVdF under high pressures. For choline [TFSI]–PVdF mixtures, PVdF may disturb the local structures of hydrogen-bonded O–H. In the absence of the C4,5–H⋯anion and C2–H⋯anion in choline [TFSI]–PVdF mixtures, the O–H group becomes a favorable moiety for pressure-enhanced IL–PVdF interactions. Our results indicate the potential of high-pressure application for designing pressure-dependent electronic switches based on the possible changes in the microheterogeneity and electrical conductivity in IL-PVdF systems under various pressures.

In Situ High-Temperature X-ray Powder Diffraction and Infrared Spectroscopic Study of Melanterite, FeSO4·7H2O

The thermal behavior of melanterite from the Fornovolasco mine (Tuscany, Italy) has been investigated via differential thermal analysis (DTA), thermogravimetry (TG), in situ high-temperature X-ray powder diffraction (XRPD) and Fourier-transform infrared spectroscopy (FTIR). The DTA curve showed endothermic peaks at 70, 100, 260, 500–560 and 660 °C whereas the TG curve evidenced a total mass decrease of ~68%, in keeping with the loss of all H2O and SO4 groups. Rietveld refinements were performed for all the collected patterns in the 25–775 °C range and converged at 1.57 ≤ R (%) ≤ 2.75 and 1.98 ≤ Rwp (%) ≤ 3.74. The decomposition steps FeSO4·7H2O → FeSO4·4H2O (25 ≤ T ≤ 50 °C) → FeSO4·H2O (50 < T ≤ 100 °C) → FeOHSO4 (75 < T ≤ 200 °C) → Fe2(SO4)3 (400 < T ≤ 500 °C) → Fe2O3 (500 < T ≤ 775 °C) were obtained. The high-temperature infrared analysis confirmed that melanterite undergoes a three-step dehydration in the 25–300 °C temperature range. The FeOHSO4 phase is stable over a wide range of temperature and transforms partially to Fe2(SO4)3 without the formation of Fe2O(SO4)2. The findings highlight a different behavior of the studied sample with respect to the synthetic salt.

Detection of new O-type stars in the obscured stellar cluster Tr 16-SE in the Carina Nebula with KMOS

Context. The Carina Nebula harbors a large population of high-mass stars, including at least 75 O-type and Wolf-Rayet (WR) stars, but the current census is not complete since further high-mass stars may be hidden in or behind the dense dark clouds that pervade the association. Aims. With the aim of identifying optically obscured O- and early B-type stars in the Carina Nebula, we performed the first infrared spectroscopic study of stars in the optically obscured stellar cluster Tr 16-SE, located behind a dark dust lane south of η Car. Methods. We used the integral-field spectrograph KMOS at the ESO VLT to obtain H- and K-band spectra with a resolution of R ≈ 4000 (Δλ ≈ 5 Å) for 45 out of the 47 possible OB candidate stars in Tr 16-SE, and we derived spectral types for these stars. Results. We find 15 stars in Tr 16-SE with spectral types between O5 and B2 (i.e., high-mass stars with M ≥ 8 M⊙), only two of which were known before. An additional nine stars are classified as (Ae)Be stars (i.e., intermediate-mass pre-main-sequence stars), and most of the remaining targets show clear signatures of being late-type stars and are thus most likely foreground stars or background giants unrelated to the Carina Nebula. Our estimates of the stellar luminosities suggest that nine of the 15 O- and early B-type stars are members of Tr 16-SE, whereas the other six seem to be background objects. Conclusions. Our study increases the number of spectroscopically identified high-mass stars (M ≥ 8 M⊙) in Tr 16-SE from two to nine and shows that Tr 16-SE is one of the larger clusters in the Carina Nebula. Our identification of three new stars with spectral types between O5 and O7 and four new stars with spectral types O9 to B1 significantly increases the number of spectroscopically identified O-type stars in the Carina Nebula.

FORMULATION AND EVALUATION OF SOLID DISPERSION TABLETS OF FUROSEMIDE USING POLYVINYLPYRROLIDONE K-30

Objective: The objective of the present study was to improve the aqueous solubility and dissolution characteristics of the loop diuretic furosemide (FUR); a class IV drug in the Biopharmaceutical Classification System (BCS) using solid dispersion technique. Methods: Solvent evaporation and kneading methods were used to produce solid dispersions of FUR in different ratios with the hydrophilic carrier polyvinylpyrrolidone K-30 (PVP-K30). The prepared solid dispersions were evaluated in terms of solubility study, percentage yield, drug content and Fourier transform infrared spectroscopic study (FT-IR). Tablets containing the optimized formula of solid dispersions ( were formulated and their dissolution characteristics were compared with commercial furosemide tablets. Results: The prepared solid dispersions showed an increase in aqueous solubility, especially those formulated in a 1:2 drug: carrier ratio using solvent evaporation method ( it showed a four-fold increase in solubility compared to the parent drug. The absence of drug-carrier chemical interactions that could affect the dissolution was proved by FT-IR. Solid dispersion tablets exhibited a better dissolution profile in simulated gastric fluid pH 1.2 at 37°C ± 0.5 than the commercial FUR tablets in terms of mean dissolution time (8.44 min) and dissolution efficiency in 30 min (42.54%). Both FUR solid dispersions and commercial tablets followed Weibull and Krosmeyer models as the two best models of drug release kinetics proving that they were immediate release. Conclusion: According to the results obtained in this study, solid dispersion techniques could be successfully used for the enhancement of aqueous solubility and dissolution rate of FUR.