http://hdl.handle.net/10453/37629 2026-06-06T02:09:41Z http://hdl.handle.net/10453/195229 Title: Amide-imidol tautomerism based fluorescence turn-on probe for selective detection of fluoride ion through restricted intramolecular rotation. Authors: Khurshid, K; Saeed, S; Assiri, MA; Shabbir, A; Shahzad, SA Abstract: Fluoride ions play a crucial role in many biological functions such as bone disease treatment, water fluoridation, and caries many other treatments. Excessive intake of fluoride ions causes chronic diseases such as Arthritis, oxidative stress, brittle bones, brain damage, and cancer. With these reasons, a cost-effective and highly specific probe 3PDA have been developed for real-time monitoring of fluoride ions. Probe 3PDA is a pyridine-based "Turn-On" sensor, easily synthesized through the Schotten-Baumann reaction. This pyridine based probe demonstrated interesting optical characteristics such as large Stoke's shift (109 nm), solvatochromism, pH sensing, and ACQ behavior. Furthermore, probe 3PDA was effectively utilized for nanomolar (nM) sensing of fluoride ions through covalent interactions. UV-visible, fluorescence, and 1H NMR titration analyses were executed to verify amide-imidol tautomerism as a sensing mechanism. Amide-imidol tautomerism become highly favorable when fluoride interacts with probe 3PDA molecule. Fluoride ion as a strong hydrogen bond acceptor facilitates the conversion of amide form into imidol tautomer and causes restriction of intramolecular rotation (RIR) of bonds. Overall, presence of fluoride ions makes probe 3PDA molecule more rigid and less flexible. Moreover, DLS analysis was executed to verify the formation of aggregation and excimer disaggregation. DFT studies were employed to validate the sensitivity of probe 3PDA toward fluoride ions. The calculated LOD was 150 nM and LOQ was 502 nM for fluoride ion detection. Probe 3PDA was employed for naked eye solid state sensing of fluoride ions under daylight and UV irradiation at 365 nm. Furthermore, 3PDA was practically applied to estimate fluoride concentration in oral care products, mineral water, and spiked lake water. 3PDA-coated TLC strips were also designed as tiny portable tools for fluoridesensing. 2025-11-15T00:00:00Z http://hdl.handle.net/10453/195127 Title: Bridging Statistical Rigor and Clinical Usability: The CORMeta App for Meta-Analysis of Correlated Outcomes Authors: Akkaya Hocagil, T; Cook, RJ; Ryan, LM Abstract: Background In clinical research, multiple outcomes are often measured within the same cohort, leading to statistical dependencies that violate assumptions of traditional meta-analytic methods. While advanced models can accommodate such correlations, they typically require programming expertise, limiting accessibility for many physician-researchers. Objective We present a user-friendly, interactive Shiny web application designed to perform meta-analyses of correlated outcomes, with particular relevance for cohort-based clinical datasets. Methods The application implements a modified multivariate meta-analytic framework that accounts for the correlation structure of outcomes within cohorts. Users can upload their data, define correlation matrices, and filter observations by any variable (e.g., age, domain, exposure) without writing code. The application provides graphical output (forest plots) along with estimates of overall effect size, heterogeneity ( ), and p-values. Results A demonstration dataset on prenatal alcohol exposure and neurodevelopmental outcomes is simulated to illustrate the application s functionality. The application automatically generates correlation matrices where needed, adjusts for intra-cohort dependencies, and produces interpretable results suitable for clinical research reports. Conclusion This open-access application bridges the gap between complex statistical modeling and clinical usability. It enables physicians to conduct robust meta-analyses of correlated outcomes with ease, supporting evidence-based practice and local research initiatives. The tool is particularly valuable in multi-domain or multi-cohort studies where outcome correlation is non-negligible. http://hdl.handle.net/10453/195019 Title: A Multimode fluorescent sensor for sequential detection of Cu2+ and cysteine as well as pH sensor with real sample Applications: Extensive experimental and DFT studies. Authors: Shabbir, A; Shahzad, SA; Alzahrani, AYA; Khan, ZA; Yar, M; Rauf, W Abstract: Highly responsive and optically selective (E)-1-((4-phenoxyphenyl) diazenyl)naphthalen-2-ol) sensor PDN with aggregation induced emission enhancement (AIEE) properties has been developed for the sequential detection of Cu2+ and L- Cysteine through fluorescence On-Off-On strategy. The selectivity of sensor depends on the presence of a diazo functional group and its appropriate cavity location in sensor molecule. Azo dye-based (E)-1-((4-phenoxyphenyl) diazenyl)naphthalen-2-ol) sensor PDN has been synthesized by utilizing a simple diazotization synthetic methodology that showed extraordinary AIEE behavior with bathochromic shift owing to the formation of J-aggregates. The morphology and size of aggregates were analyzed by SEM and DLS analysis, respectively. The calculated LOD of sensor PDN for Cu2+, and L-cysteine is 0.113 nM, and 84 nM, respectively. Fluorescence, UV-visible, LC-MS, 1H and 13C NMR titration were carried out to understand the interaction of sensor with Cu2+. The sensor was practically utilized in the sequential sensing of Cu2+ and Cys in real samples. Interestingly, sensor PDN was successfully employed for the sensing of a strong acid and base as well as the detection of Cu2+ ions in the solid state. Moreover, these experimental results were supported through DFT calculations. 2025-02-15T00:00:00Z http://hdl.handle.net/10453/195016 Title: Cocrystal mitigates the effects of elevated gastric pH on oral absorption of weakly basic drugs: a case study with ketoconazole-succinic acid cocrystal on beagle dogs. Authors: Tucci, YM; Machado, TC; Sun, D; Rodríguez-Hornedo, N Abstract: It is well documented that weakly basic drugs, such as ketoconazole (KTZ), will exhibit reduced oral absorption and lower bioavailability in elevated gastric pH conditions. Because this occurs frequently in patients taking medicines to reduce stomach acid, it is crucial to identify formulation strategies that ensure adequate drug exposure. The purpose of this work was to evaluate the in vitro and in vivo effects of KTZ cocrystals with acidic coformers in mitigating the negative effects of elevated gastric pH on KTZ dissolution and absorption after oral administration. Dissolution-supersaturation-precipitation in vitro studies were performed with drug and three KTZ cocrystals with fumaric (FUM), adipic (ADP), and succinic (SUC) acids, under a two-stage pH-shift micro dissolution method, to mimic the transfer from gastric to intestinal compartment. All cocrystals exhibited less sensitivity to elevated gastric pH than the drug. In vitro, cocrystals reduced the area under the curve (AUC) 2.6-fold compared to drug where AUC decreased 6.7-fold. Based on the superior performance observed during in vitro studies, the KTZ-SUC cocrystal was selected for bioavailability evaluation in beagle dogs treated with pentagastrin and famotidine to simulate normal and elevated gastric conditions. The cocrystal mitigated the negative effects of elevated dog gastric pH on KTZ absorption. It reduced the pH sensitivity of AUC (1.3 times) and Cmax (1.4 times). The drug exhibited high pH sensitivity with reduced AUC (12.3 times) and Cmax (7.5 times). These findings demonstrate that cocrystals of weakly basic BCS-class II drugs with acidic coformers promise to improve therapeutic outcomes that are otherwise limited by disease states or co-administration of drugs and food that increase gastric pH. 2026-05-08T00:00:00Z