Photophysical Properties of Sinapic Acid and Ferulic Acid and Their Binding Mechanism with Caffeine.

Sinapic acid (SA) and ferulic acid (FA) are bioactive compounds used in the food, pharmaceutical, and cosmetic industries due to their antioxidant properties. In this work, we studied the photophysical properties of SA and FA in different solvents and concentrations and their interactions with caffeine (CF), using ultraviolet-visible (UV-Vis), fluorescence spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The findings show that the quantum yield, fluorescence lifetime, radiative decay rates, and non-radiative decay rates of SA and FA are influenced by the concentrations and solvent polarity. The interaction between SA and FA with CF was also studied using UV-Vis and fluorescence spectroscopy. The results indicate that the CF quenched the fluorescence intensity of SA and FA by static quenching due to the formation of a non-fluorescent complex. The van't Hoff equation suggests that the van der Waals forces and hydrogen bonds force were responsible for the interaction between SA and CF, as indicated by a negative change in enthalpy ( Δ H o  < 0) and a negative change in entropy ( Δ S o  < 0). On the other hand, the interaction between FA and CF was primarily controlled by electrostatic force, as indicated by a negative change in enthalpy ( Δ H o < 0) and a positive change in entropy ( Δ S o > 0). The negative change in Gibbs free energy ( Δ G o ) indicates that both compounds underwent a spontaneous binding process.

Ground and Excited State Dipole Moments of Metformin Hydrochloride using Solvatochromic Effects and Density Functional Theory.

In this research, the ground (µg) and excited (µe) state dipole moments of metformin hydrochlorides were determined using Lippert-Mataga, Bakhshiev's, Kawski-Chamma-Viallet, and Reichardt models from fluorescence emission and UV-Vis absorption spectra in various solvents. From solvatochromic effects the calculated excited (µe ) dipole moment of metformin hydrochloride were, 8.55 D, 8.34 D, 6.08 D, and 6.40 D using the Lippert-Mataga, Bakhshiev's, Kawski-Chamma-Viallet and Reichardt models respectively. The results also indicated that the dipole moment at the ground state is smaller than the excited state. This is due to solvent polarity having a stronger effect on fluorescence emission than absorption spectra. Similarly, from density functional theory, the calculated ground and excited states dipole moments of metformin hydrochloride using (DFT-B3LYP- 3-21+G*(µg = 10.02 D and µe = 11.94 D), DFT-B3LYP- 6-31+G (d, p) (µg = 8.44 D and µe = 10.87 D), and DFT-B3LYP- 6-311+G (d, p) (µg = 8.24 D and µe = 18.74 D)) analyzed by Gaussian 09W. From the optimized geometry of the molecule, the HOMO-LUMO energy band gap of metformin hydrochloride were computed using DFT [DFT-B3LYP- 3-21+G*(5.51 eV), DFT-B3LYP- 6-31+G (d, p) (5.66 eV), and DFT-B3LYP- 6-311+G (d, p) (5.70 eV)] respectively.

Noble classical and quantum approach to model the optical properties of metallic nanoparticles to enhance the sensitivity of optoplasmonic sensors.

The bright light obtained from the quantum principle has a key role in the construction of optical sensors. Yet, theoretical and experimental work highlights the challenges of overcoming the high cost and low efficiency of such sensors. Therefore, we report a metallic nanoparticle-based metasurface plasmons polariton using quantum and classical models. We have investigated the material properties, absorption cross-section, scattering cross-section, and efficiency of the classical model. By quantizing light-matter interaction, the quantum features of light - degree of squeezing, correlation, and entanglement are quantified numerically and computationally. In addition, we note the penetration depth and propagation length from a hybrid model in order to enhance the optoplasmonic sensor performance for imaging, diagnosing, and early perception of cancer cells with label-free, direct, and real-time detection. Our study findings conclude that the frequency of incident light, size, shape, and type of nanoparticles has a significant impact on the optical properties of metallic nanoparticles and the nonlinear optical properties of metallic nanoparticles are dynamic, enhancing the sensitivity of the optoplasmonic sensor. Moreover, the resulting bright light shows the systematic potential for further medical image processing.

Factors affecting demand for modern contraceptives among currently married reproductive age women in rural Kebeles of Nunu Kumba district, Oromia, Ethiopia.

BACKGROUND: Family planning plays a key role in improving the health of the mother and the child. Yet there are still significant levels of demand for family planning that are unmet and these can lead to unintended pregnancy. So, women's demand for contraceptive utilization to limit, space, or delay the number of family size can be increased by integrating family planning service at each service delivery points. OBJECTIVE: The main aim of this study was to assess the demand for modern contraceptive and associated factors among currently married women of the reproductive age group in rural kebeles of Nunu Kumba District, 2015. METHODS: A community-based cross-sectional study design was conducted from January 15-30, 2015 among 584 systematically selected currently married women of reproductive age in six rural kebeles of Nunu Kumba District. A pre-tested and interviewer-administered questionnaire was used to collect the data. Data were analyzed using SPSS version 20. Descriptive statistics were done to summarize the data. A multivariate logistic regressions analysis method was employed and odds ratio with 95% confidence interval was used to control for possible confounders. P-value < 0.05 was used to declare a significant association. RESULTS: The total demand for modern methods of contraceptive was 450 (77.1%) of which 325 (55.7%) of them were current user and 125 (21.4%) of them were had unmet need for modern contraceptive methods. Being in the younger age group (15-24 and 25-34 years [AOR = 0.196; 95% CI: 0.055, 0.692] and [AOR = 0.179, 95% CI: 0.043, 0.745] respectively, husband having no intention for more children [AOR = 4.124, 95% CI: 1.891, 8.996], number of children alive [AOR = 2.617, 95% CI: 1.056, 6.486], and couples ever not discussed on family planning [AOR = 0.340, 95% CI: 0.187, 0.619] were factors associated with demand for modern methods of contraception. CONCLUSION: The total demand for modern methods of contraceptive was high in the study area except for long-acting and permanent methods with high unmet need for spacing than for limiting. Therefore, any program aimed at promoting family planning at the district level should look for ways and means of increasing demand for long-acting and permanent family planning methods and encouraging husband involvement to increase its utilization.

Controlled synthesis, characterization, and application of iron oxide nanoparticles for oral delivery of insulin.

Impurity-free, controlled synthesis of iron oxide nanoparticle, in ultrapure water and chitosan, using laser ablation technique and its application for type II diabetes management through oral delivery of insulin-loaded iron oxide-chitosan nanocomposite is presented. The purity of the nanoparticle is monitored by laser-induced breakdown spectroscopy technique. The synthesized iron oxide nanoparticle was characterized by UV/Vis absorption spectroscopy, and morphological study was performed by scanning electron microscope. The intensity of absorption peak and wavelength corresponding to peak of the nanoparticle prepared in water and chitosan is dependent on the laser energy used for ablation purpose. Red shift in the absorption peak wavelength was observed by increasing laser energy. In addition to red shift, an increase in intensity of absorption peak was also seen when ablating laser energy was increased. The appearance of a weak peak around 295 nm was observed in iron oxide-chitosan nanocomposite. The spherical shape of the nanoparticle synthesized at the lower laser energy has gradually changed to triangular and irregular shaped structures as ablating laser energy was increased. The spherical nanoparticles loaded with insulin were used for oral delivery for diabetic management. The iron oxide-chitosan nanocomposite loaded with insulin has resulted in reduction in blood glucose level in mild diabetic, subdiabetic, and severely diabetic rats; more than 51 % reduction in blood glucose level, compared to the control group, has been achieved in the present work.