Dual modulation of blue-fluorescent carbon dots for simultaneous detection of topotecan and pantoprazole.

This study introduces a novel approach for the simultaneous determination of topotecan (TOP) and pantoprazole (PNT), two drugs whose interaction is critical in clinical applications. The significance of this study originates from the need to understand the pharmacokinetic changes of TOP after PNT administration, which can inform necessary dose adjustments of TOP. To achieve this, nitrogen blue emissive carbon dots (B@NCDs) were produced and employed due to their unique fluorescent properties. When TOP is added to B@NCDs, it exhibits strong native fluorescence at 545 nm without influencing the B@NCDs' fluorescence at 447 nm. Conversely, PNT causes quenching of B@NCDs fluorescence, a property that enables the distinct detection of both drugs. The B@NCDs were fully characterized using different techniques, including ultraviolet-visible spectrophotometry, fluorescence analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM), and FTIR spectroscopy. The proposed method demonstrated excellent linearity, selectivity, and sensitivity, with low detection limits (LOD, S/N = 3); 0.0016 µg mL-1 for TOP and 0.36 µg mL-1 for PNT. Applied to spiked rabbit plasma samples, this method offers a new approach for evaluating the pharmacokinetic interaction between TOP and PNT. It enables the determination of all pharmacokinetic parameters of TOP before and after coadministration with PNT, providing essential insights into whether dose adjustments are necessary. This research not only contributes to the field of drug monitoring and interaction studies but also exemplifies the potential of B@NCDs in complex biological matrices, paving the way for further pharmacological and therapeutic applications.

Development and Validation of Chromatographic Methods for Simultaneous Estimation of Aspirin and Pantoprazole Sodium in Pure and Mixture Form.

This technique is employed for the simultaneous quantification of aspirin (ASP) and pantoprazole sodium in both pure powder form and formulations. The high performance liquid chromatography (HPLC) method uses a C-18 column (250 mm × 4.6 mm, 5 µm) with a mobile phase consisting of 0.05 M disodium hydrogen phosphate and methanol in a 40:60% v/v ratio. The flow rate is maintained at 1.0 mL/min. On a layer of silica gel 60F254 with an aluminum backing, the high performance thin layer chromatography (HPTLC) separation was carried out with ethyl acetate and methanol (8: 1.5 v/v) as the mobile phase. With a mean recovery of 100.54% and 99.55% for ASP and PNT, respectively, quantification was accomplished using the HPLC method with UV detection at 286 nm over the concentration range of 0.1-0.6 g/mL for PNT and 0.4-2.4 g/mL for ASP. With a mean recovery of 99.44% and 99.01% for ASP and PNT, respectively, quantification was achieved using the HPTLC method with UV detection at 298 nm over the concentration range of 400-2400 ng/spot for ASP and 100-600 ng/spot for PNT, respectively. The methods can be used for the simultaneous determination of ASP and PNT in pure powder form and formulations as they are simple, accurate and sensitive.

Spectroscopic study of in situ-formed metallocomplexes of proton pump inhibitors in water.

Proton pump inhibitors, such as omeprazole, pantoprazole and lansoprazole, are an important group of clinically used drugs. Generally, they are considered safe without direct toxicity. Nevertheless, their long-term use can be associated with a higher risk of some serious pathological states (e.g. amnesia and oncological and neurodegenerative states). It is well known that dysregulation of the metabolism of transition metals (especially iron ions) plays a significant role in these pathological states and that the above drugs can form complexes with metal ions. However, to the best of our knowledge, this phenomenon has not yet been described in water systems. Therefore, we studied the interaction between these drugs and transition metal ions in the surrounding water environment (water/DMSO, 99:1, v/v) by absorption spectroscopy. In the presence of Fe(III), a strong redshift was observed, and more importantly, the affinities of the drugs (represented as binding constants) were strong enough, especially in the case of omeprazole, so that the formation of a metallocomplex cannot be excluded during the explanation of their side effects.

Peroxidation and photo-peroxidation of pantoprazole in aqueous solution using silver molybdate as catalyst.

In this study, silver molybdate was used as a catalyst in different oxidation processes to degrade pantoprazole (PAN) from aqueous suspension. The catalyst was synthesized using a controlled precipitation method and characterized by XRD, FTIR spectroscopy, BET analysis, Zeta potential, FEG-SEM/EDS, DRS and EPR. The α- and ß-phases of Ag2MoO4 were identified as crystalline structure of the butterfly-shaped particles. The metastable α-phase could be completely converted into ß-Ag2MoO4 by thermal treatment at 300 °C. The band gap energy of ß-Ag2MoO4 (Eg = 3.25 eV) is slightly higher than for as-prepared catalyst (α-Ag2MoO4 + ß-Ag2MoO4) (Eg = 3.09 eV), suggesting that as-prepared catalyst should be active under visible light. PAN is sensible to UV light irradiation, and the addition of H2O2 as electron acceptor enhanced the mineralization rate. In the catalytic UV-based reactions, high PAN oxidation efficiencies were obtained (>85%) but with low mineralization (32-64%). Catalytic peroxidation and photo-catalytic peroxidation under visible light showed the highest PAN oxidation efficiency, leading to its almost complete mineralization (>95%), even under dark conditions (98% in 120 min). Several degradation byproducts were identified and three mechanistic routes of PAN decomposition were proposed. The identified byproducts are less toxic than the parent compound. EPR coupled with the spin trapping method identified •OH radicals as the main ROS species in both photocatalytic and catalytic peroxidation reactions. Ag2MoO4 showed to be a promising catalyst to promote the decomposition of hydrogen peroxide into ROS.1.

A Sensitive, Simple and Direct Determination of Pantoprazole Based on a "Turn off-on" Fluorescence Nanosensor by Using Terbium-1,10-phenanthroline-silver Nanoparticles.

A new sensitive, simple, rapid, reliable and selective fluorometric method for the determination of pantoprazole (PAN) in human plasma and a pharmaceutical formulation has been developed. This technique is based on a quenching effect of silver nanoparticles (AgNPs) on the emission intensity of a fluorescent probe, terbium(III)-1,10-phenantroline (Tb(III)-phen) complex (due to a fluorescence resonance energy transfer (FRET) phenomenon between the Tb(III)-phen complex and AgNPs), and then restoring the fluorescence intensity of the Tb(III)-phen-AgNPs system upon the addition of PAN (turn off-on process). The effects of various factors on the proposed method including time, temperature, pH, order of the addition of various reagents and the concentration of AgNPs were investigated. Under the optimal conditions, a good linear relationship between the enhanced emission intensity of the Tb(III)-phen-AgNPs system and the PAN concentration was observed in the range of (10 - 1000) × 10-8 M. The limit of detection (LOD) and the limit of quantitation (LOQ) were 7.2 × 10-8 and 24.2 × 10-8 M, respectively. Also, the interferences of some common interfering species on the fluorescence intensity of the system were investigated. This simple and sensitive method was successfully applied for the determination of PAN in spiked human plasma samples and in its capsule formulation. The analytical recoveries were in the range of 88.54 - 101.33 and 90.07 - 98.85%, respectively.

Inhibition of monoglyceride lipase by proton pump inhibitors: investigation using docking and in vitro experiments.

BACKGROUND: Currently, there is overwhelming evidence linking elevated plasma free fatty acids with insulin resistance and inflammation. Monoglyceride lipase (MGL) plays a crucial metabolic role in lipolysis by mediating the release of fatty acids. Therefore, inhibiting MGL should be a promising pharmacological approach for treating type 2 diabetes and inflammatory disorders. Proton pump inhibitors (PPIs) have been reported to improve glycemic control in type 2 diabetes albeit via largely unknown mechanism. METHODS: The anti-MGL bioactivities of three PPIs, namely, lansoprazole, rabeprazole, and pantoprazole, were investigated using docking experiments and in vitro bioassay. RESULTS: The three PPIs inhibited MGL in low micromolar range with rabeprazole exhibiting the best IC50 at 4.2 µM. Docking experiments showed several binding interactions anchoring PPIs within MGL catalytic site. CONCLUSION: Our study provides evidence for a new mechanism by which PPIs improve insulin sensitivity independent of serum gastrin. The three PPIs effectively inhibit MGL and, therefore, serve as promising leads for the development of new clinical MGL inhibitors.

Intragastric pH effect of 20mg of levo-pantoprazole versus 40mg of racemic pantoprazole the first seven days of treatment in patients with gastroesophageal reflux disease. / Efecto sobre el pH intragástrico de 20mg de levopantoprazol versus 40mg de pantoprazol racémico durante los primeros 7 días de tratamiento en pacientes con enfermedad por reflujo gastroesofágico.

INTRODUCTION/AIM: Levo-pantoprazole, the S-enantiomer of pantoprazole, is a proton pump inhibitor that has been shown in animal studies to be faster and stronger than its racemic formulation. There are no studies on humans and therefore our aim was to evaluate the effects of levo-pantoprazole versus racemic pantoprazole on intragastric pH. MATERIALS AND METHODS: A randomized controlled study was conducted on patients with erosive gastroesophageal reflux disease that were given 20mg of levo-pantoprazole (n = 15) versus 40mg of racemic pantoprazole (n = 15) for 7 days. Baseline and end-of-treatment symptom evaluation and intragastric pH measurement were carried out. RESULTS: There were no differences between the groups in the baseline evaluations. From 40 to 115min after the first dose of levo-pantoprazole, the mean intragastric pH was higher, compared with that of racemic pantoprazole (p < 0.05). After one week, levo-pantoprazole and racemic pantoprazole significantly reduced intragastric acid production and its esophageal exposure (p < 0.05). Even though there was no statistically significant difference, a larger number of patients that received levo-pantoprazole stated that their heartburn improved within the first 3 days. CONCLUSIONS: The S-enantiomer of pantoprazole (levo-pantoprazole) had a faster and stronger effect with respect to acid suppression, compared with its racemic formulation. Although the effect on symptoms was faster with levo-pantoprazole, occurring within the first days of treatment, it was equivalent to that of the racemate at one week of treatment.

Optimization of the coating process of minitablets in two different lab-scale fluid bed systems.

The optimization of the coating process for minitablets is extremely important in fluidized bed systems, and allows knowledge acquisition about the process for modern multiparticulate forms. The coating of minitablets allows the development of modified-release pediatric drugs. In our study, 3-mm minitablets with pantoprazole were coated to obtain an enteric product. The experiments were designed to evaluate the quality of the enteric product by efficiency and quality of film coating. Four process parameters at two levels were examined, and 16 experiments for two different fluid bed systems in laboratory-scale batches were performed. During analysis, the critical parameters of inlet airflow rate (X1) and coating mixture flow rate (X3) in different fluid bed coaters were examined. The findings indicate that apparatus construction has a significant effect on the different process parameters. Despite the fact that statistical analysis is directly related to the tested conditions, it creates opportunity to anticipate certain problems while scaling up, and a possibility to minimize them.

Comparison of the coating process and in vitro dissolution of 3 mm gastro-resistant minitablets and 5 mm gastro-resistant tablets with pantoprazole.

Minitablets are solid oral forms, which, due to their size (1-3 mm), may be easily swallowed by children. The administration of minitablets in a certain number of units allows for flexible dosing for a broad age group of paediatric patients, which is particularly important for modified-release drugs. In this study, enteric-coated minitablets (3 mm) with pantoprazole were developed and compared to conventional tablets (5 mm). Eudragit L 30D 55® and Acryl Eze II® films, which were 50 and 80 µm thick, respectively, were applied using two different fluid bed systems. The increase in the pantoprazole release rate occurred not only due to the application of a thinner film but also due to the reduction in the size of the core independent of the coating apparatus that was used. In contrast to minitablets, the thin film's thickness was insufficient for 5 mm tablets and a loss of gastro-resistance was observed. The insertion of minitablets into a hard gelatine capsule did not affect drug release from the minitablets under in vitro conditions.

Comparison of Active Substance Losses and Total Weight Losses of Tablets Administered Via Feeding Tube.

BACKGROUND/AIMS: Administration of tablets via feeding tube (FT) is often associated with significant drug losses, as was confirmed by weighing. The aim of this study was to measure the proportion of active substance losses (ASLs) in an in vitro model. METHODS: A film-coated tablet (FilmCT) containing clopidogrel (Trombex®) and a tablet with enteric coating (EntericCT) containing pantoprazole (Controloc®) were crushed in a mortar and transferred by method A (tablet powder was transferred into the beaker, poured into the syringe and water added) and method B (water was added into the mortar, suspension drawn into the syringe) and administered via FT in an in vitro model. Total losses were measured with analytical balance and, simultaneously, ASL were analyzed with high-performance liquid chromatography UV-detection (HPLC-UV). RESULTS: ASL was different to weighing only in the case of EntericCT prepared by method B (2.0 ± 4.2 and 10.7 ± 0.8% for HPLC-UV and weighing, respectively; p = 0.004). HPLC-UV confirmed significantly lower ASL when method B was used for either EntericCT (34.3 ± 7.2 vs. 2.0 ± 4.2%; p < 0.001) or FilmCT (14.1 ± 2.2 vs. 7.7 ± 4.1%; p < 0.01). CONCLUSION: Drug loss analysis with analytical balance may overestimate ASL, as was proved for EntericCT in this study. ASL were significantly lower when method B was used.

Development and pharmacokinetic evaluation of alginate-pectin polymeric rafts forming tablets using box behnken design.

Raft is an emerging drug delivery system, which is suitable for controlled release drug delivery and targeting. The present study aimed to evaluate the physico-chemical properties of raft, in vitro release of pantoprazole sodium sesquihydrate and conduct bioavailability studies. Box behnken design was used with three independent and dependent variables. Independent variables were sodium alginate (X1), pectin (X2) and hydroxypropyl methyl cellulose K100M (X3) while dependent variables were percentage drug release at 2 (Y2), 4 (Y4) and 8 h (Y8). The developed rafts were evaluated by their physical and chemical properties. Fourier transform infrared spectroscopy and differential scanning calorimetry were used to study the chemical interaction and thermal behaviour of drug with polymers. Alginate and pectin contents of R9 formulation were 99.28% and 97.29%, respectively, and acid neutralization capacity was 8.0. R9 formulation showed longer duration of neutralization and nature of raft was absorbent. The raft of R9 formulation showed 98.94% release of PSS at 8 h in simulated gastric fluid. Fourier transform infrared spectroscopy showed no chemical interaction and differential scanning calorimetry indicated endothermic peaks at 250 °C for pantoprazole sodium sesquihydrate. tmax for the test and reference formulations were 8 ± 2.345 h and 8 ± 2.305 h, respectively. Cmax of test and reference formulations were 46.026 ± 0.567 µg/mL and 43.026 ± 0.567 µg/mL, respectively. AUC(0-t) of the test and reference formulations were 472.115 ± 3.467 µg × h/mL and 456.105 ± 2.017 µg × h/mL, respectively. Raft forming system successfully delivered the drug in controlled manner and improved the bioavailability of drugs.

Development of a dual extrusion printing technique for an acid- and thermo-labile drug.

Over the last years fused deposition modeling has been increasingly considered as a game-changing technique for the preparation of individualized pharmaceutical products. Until now investigations have mainly focused on dosage forms loaded with very stable drugs or model substances. Going beyond this early stage of research, developers will also have to deal with more challenging active substances. In this work different printing designs for tablets containing the acid- and thermo-labile drug pantoprazole sodium were tested. Initial dual extrusion printing of a cellulose acetate phthalate coat and a tablet core of polyethylene glycol 6000 with 10% (m/m) pantoprazole sodium resulted in thermal degradation of pantoprazole at cellulose acetate phthalate printing temperatures of 141 °C. Therefore, different tablet designs were developed. The sectioning of the design of the tablet coat in a gastro-resistant cellulose acetate phthalate bottom part and an upper nearly insoluble polycaprolactone part printed at only 58 °C was suitable to prevent visible signs of thermal degradation. Dissolution testing indicated also no drug loss during dual extrusion printing. However, printed enteric tablets with shell thicknesses of 0.4 to 0.5 mm were not completely gastro-resistant. Drug release at intestinal pH values was delayed compared to uncoated cores. In conclusion, 3D-printing of gastro-resistant tablets containing thermo- and acid-labile drugs seems in principle possible. However, it remains an unsolved challenge to meet United States Pharmacopeia requirements.

The proton pump inhibitor pantoprazole disrupts protein degradation systems and sensitizes cancer cells to death under various stresses.

Proton pump inhibitors (PPIs) play a role in antitumor activity, with studies showing specialized impacts of PPIs on cancer cell apoptosis, metastasis, and autophagy. In this study, we demonstrated that pantoprazole (PPI) increased autophagosomes formation and affected autophagic flux depending on the pH conditions. PPI specifically elevated SQSTM1 protein levels by increasing SQSTM1 transcription via NFE2L2 activation independent of the specific effect of PPI on autophagic flux. Via decreasing proteasome subunits expression, PPI significantly impaired the function of the proteasome, accompanied by the accumulation of undegraded poly-ubiquitinated proteins. Notably, PPI-induced autophagy functioned as a downstream response of proteasome inhibition by PPI, while suppressing protein synthesis abrogated autophagy. Blocking autophagic flux in neutral pH condition or further impairing proteasome function with proteasome inhibitors, significantly aggravated PPI cytotoxicity by worsening protein degradation ability. Interestingly, under conditions of mitochondrial stress, PPI showed significant synergism when combined with Bcl-2 inhibitors. Taken together, these findings provide a new understanding of the impact of PPIs on cancer cells' biological processes and highlight the potential to develop more efficient and effective combination therapies.

Preparation and Characterization of a Novel Aqueous Dispersion for Enteric Coating of Pantoprazole Sodium Pellets.

The purpose of this work was to investigate a novel aqueous dispersion (Eudragit® L100-55) f or e nteric c oating o f drugs. Three different casting solutions, Eudragit® L100-55 aqueous dispersion, Eudragit® L 100-55 o rganic s olution, and Eudragit® L30D-55 aqueous dispersion, were used to prepare free films by the casting method. Drug-loaded pellets, prepared by the extrusion-spheronization method, were coated with one of these three coating solutions using the fluidized-bed spray coating technology. Properties of the free films were thoroughly investigated. Films formed by Eudragit® L100-55 aqueous dispersions showed similar properties to those formed by Eudragit® L100-55 organic solution regarding thermodynamic properties, moisture permeability, solubility and acid tolerance ability. Furthermore, the performance of the novel film was better than that formed by Eudragit® L30D-55 aqueous dispersion. Among the three enteric coating solutions, Eudragit® L100- 55 aqueous dispersion will be a promising aqueous dispersion for enteric coating and can be used in the development of enteric-coated preparations.

[Characterization and stability of S (-) pantoprazole sodium hydrates].

Objective: To study the characteristics and stability of new S(-) pantoprazole sodium hydrates. Methods: The X-ray single crystal diffractometer (SXRD), X-ray powder diffractometer (PXRD), thermogravimetric analysis (TG) and infrared spectrometry (IR) were used to characterize S(-) pantoprazole sodium hydrates. The stability of the hydrates was evaluated by high temperature test,affecting factors test and accelerated test. Results: The crystalline water in S(-) pantoprazole sodium hydrates were very easy to lose and obtain, but crystal structure was not changed significantly. The transition from S(-) pantoprazole sodium trihydrate to S(-) pantoprazole sodium hemipentahydrate occurred at approximately 40 ℃ and reversible transitions from hemipentahydrate to trihydrate occurred at high humidity. Two hydrates had no significant difference in accelerated test. Conclusion: The crystal structure of the two hydrates are almost the same, hemipentahydrate is more stable than trihydrates at high temperature or at exposure to light(at 4500 ± 500 lx).