A Biphasic Dissolution Method to Mimic Oral Absorption from Simulated Animal Gastrointestinal Fluids

Ketoconazole is an imidazole antifungal drug belonging to the class II of Biopharmaceutic Classification System. Maintenance of gastric acidity is essential for adequate dissolution and absorption of ketoconazole. Concurrent administration of antacid and antiulcer preparations decreases the oral absorption of ketoconazole often causing therapeutic failure. The aim of this study was to evaluate whether a self-emulsifying formulation of ketoconazole would be able to overcome the pH dependent dissolution and oral bioavailability. Self-emulsifying drug delivery system (SEDDS) was prepared after selecting the oil, surfactant and co-surfactant by solubility analysis. Optimum ratio of the components was finalized on the basis of drug content, self-emulsification and mean droplet diameter. The effect of pH on dissolution was studied in comparison to the pure drug. Oral bioavailability was determined in comparison to aqueous suspension in rats and the effect of co-administration of ranitidine hydrochloride solution and a commercially available liquid antacid preparation was studied. The optimized formulation containing 20% Capryol 90 and 40% each of Carbitol and Tween 80, exhibited 100% drug release regardless of the pH whereas the pure drug exhibited a highly pH dependent dissolution. The AUC0-24 resulted with oral administration of the SEDDS formulation was about 34%, 43% and 60% higher compared to the aqueous suspension when administered alone, administered with ranitidine and administered with antacid respectively. The results of the present study demonstrate that self-emulsifying formulations can be utilized for oral delivery of weakly basic drugs like ketoconazole which exhibit pH dependent dissolution.

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Formulation and Evaluation of Solubility Enhanced Ciprofloxacin

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2013.6.3.4 ◽

2013 ◽

Vol 6 (3) ◽

pp. 2131-2136

Author(s):

R S Thakur ◽

A Nayaz ◽

Y Koushik

Keyword(s):

Oral Absorption ◽

Polymeric Micelles ◽

In Vitro Release ◽

Microemulsion System ◽

Salt Form ◽

Solubility Study ◽

Ternary Phase Diagrams ◽

Blood Ph ◽

Vitro Release

In the case of solubility limited absorption, creating supersaturation in the GI fluid is very critical as supersaturation may provide great improvement of oral absorption. The techniques to create the so-called supersaturation in the GI fluid include microemulsions, emulsions, liposomes, complexations, polymeric micelles, and conventional micelles. Ciprofloxacin was chosen because it is practically insoluble in water; hence its salt form is used commercially, which is soluble in water. The objective of the present investigation was to enhance the solubility of Ciprofloxacin by formulating it into microemulsion system. For this purpose, initially, surfactant and cosurfactant were selected based on their HLB value, followed by pseudo-ternary phase diagrams to identify the microemulsion existing zone. Different formulations were developed and evaluated for pH, conductivity, in vitro release and stability. Solubility study was performed for optimized formulation. The pH of the designed formulations varied from 6.02-7.04. This was ideal and near blood pH 7.4. Conductivity data indicated that the microemulsion was of the o/w type. In vitro release of optimized formulation(FM3) was 95.2% as compared to pure drug 46.61% after 90 min and marketed product(salt form) 93.9%. Hence, by formulating into microemulsion, the solubility of ciprofloxacin is significantly enhanced.

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Nanoparticles Functionalized with Venom-Derived Peptides and Toxins for Pharmaceutical Applications

Current Pharmaceutical Biotechnology ◽

10.2174/1389201020666190621104624 ◽

2020 ◽

Vol 21 (2) ◽

pp. 97-109 ◽

Cited By ~ 1

Author(s):

Ana P. dos Santos ◽

Tamara G. de Araújo ◽

Gandhi Rádis-Baptista

Keyword(s):

Oral Absorption ◽

Current Data ◽

Pharmacological Activities ◽

Venom Peptides ◽

Essential Components ◽

Wide Range ◽

Different Types ◽

Direct Use ◽

Animal Venoms ◽

Pharmaceutical Biotechnology

Venom-derived peptides display diverse biological and pharmacological activities, making them useful in drug discovery platforms and for a wide range of applications in medicine and pharmaceutical biotechnology. Due to their target specificities, venom peptides have the potential to be developed into biopharmaceuticals to treat various health conditions such as diabetes mellitus, hypertension, and chronic pain. Despite the high potential for drug development, several limitations preclude the direct use of peptides as therapeutics and hamper the process of converting venom peptides into pharmaceuticals. These limitations include, for instance, chemical instability, poor oral absorption, short halflife, and off-target cytotoxicity. One strategy to overcome these disadvantages relies on the formulation of bioactive peptides with nanocarriers. A range of biocompatible materials are now available that can serve as nanocarriers and can improve the bioavailability of therapeutic and venom-derived peptides for clinical and diagnostic application. Examples of isolated venom peptides and crude animal venoms that have been encapsulated and formulated with different types of nanomaterials with promising results are increasingly reported. Based on the current data, a wealth of information can be collected regarding the utilization of nanocarriers to encapsulate venom peptides and render them bioavailable for pharmaceutical use. Overall, nanomaterials arise as essential components in the preparation of biopharmaceuticals that are based on biological and pharmacological active venom-derived peptides.

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Design and Synthesis of Novel Anti-inflammatory/Anti-ulcer Hybrid Molecules with Antioxidant Activity

Medicinal Chemistry ◽

10.2174/1573406416666200930114340 ◽

2020 ◽

Vol 16 ◽

Author(s):

Bhim Bahadur Chaudhari ◽

Alka Bali ◽

Ajitesh Balaini

Keyword(s):

Antioxidant Activity ◽

Oral Absorption ◽

Radical Scavenging ◽

Reducing Power ◽

Antioxidant Potential ◽

Inflammatory Activity ◽

In Vivo Models ◽

Standard Drug ◽

Hybrid Molecules ◽

Anti Inflammatory

Background: NSAIDs are the most widely prescribed medications worldwide for their anti-inflammatory, antipyretic, and analgesic effects However, their chronic use can lead to several adverse drug events including GI toxicity. The selective COX-2 inhibitors developed as gastro-sparing NSAIDs also suffer from serious adverse effects which limit their efficacy. Objective: Local generation of reactive oxygen species is implicated in NSAID-mediated gastric ulceration and their combination with H2 antagonists like famotidine reduces the risk of ulcers. The objective of this work was to design and synthesize novel methanesulphonamido isoxazole derivatives by hybridizing the structural features of NSAIDs with those of antiulcer drugs (ranitidine, famotidine, etc.) to utilize a dual combination of anti-inflammatory activity and reducing (antioxidant) potential. Method: The designing process utilized three dimensional similarity studies and utilized an isoxazole core having a potential for anti-inflammatory as well as radical scavenging antioxidant activity. The compounds were assayed for their antiinflammatory activity in established in vivo models. The in vitro antioxidant activity was assessed in potassium ferricyanide reducing power (PFRAP) assay employing ascorbic acid as the standard drug. Results: Compounds (5, 6, 9 and 10) showed anti-inflammatory activity comparable to the standard drugs and were also found to be non-ulcerogenic at the test doses. Compounds 6-10 exhibited good antioxidant effect in the concentration range of 1.0-50.0 µmol/ml. The test compounds were also found to comply with the Lipinski rule suggesting good oral absorption. Conclusion: A new series of isoxazole based compounds is being reported with good anti-inflammatory activity coupled with antioxidant potential as gastro-sparing anti-inflammatory agents.

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In Silico Appraisal, Synthesis, Antibacterial Screening and DNA Cleavage for 1,2,5-thiadiazole Derivative

Current Computer - Aided Drug Design ◽

10.2174/1573409915666190206142756 ◽

2019 ◽

Vol 15 (5) ◽

pp. 445-455 ◽

Cited By ~ 6

Author(s):

Suraj N. Mali ◽

Sudhir Sawant ◽

Hemchandra K. Chaudhari ◽

Mustapha C. Mandewale

Keyword(s):

Molecular Docking ◽

Dna Cleavage ◽

In Silico ◽

Oral Absorption ◽

Inhibition Mechanism ◽

Hydrogen Binding ◽

Docking Score ◽

Antibacterial Screening ◽

Mycobacteria Tuberculosis

Background: : Thiadiazole not only acts as “hydrogen binding domain” and “two-electron donor system” but also as constrained pharmacophore. Methods:: The maleate salt of 2-((2-hydroxy-3-((4-morpholino-1, 2,5-thiadiazol-3-yl) oxy) propyl) amino)- 2-methylpropan-1-ol (TML-Hydroxy)(4) has been synthesized. This methodology involves preparation of 4-morpholino-1, 2,5-thiadiazol-3-ol by hydroxylation of 4-(4-chloro-1, 2,5-thiadiazol-3-yl) morpholine followed by condensation with 2-(chloromethyl) oxirane to afford 4-(4-(oxiran-2-ylmethoxy)-1,2,5-thiadiazol- 3-yl) morpholine. Oxirane ring of this compound was opened by treating with 2-amino-2-methyl propan-1- ol to afford the target compound TML-Hydroxy. Structures of the synthesized compounds have been elucidated by NMR, MASS, FTIR spectroscopy. Results: : The DSC study clearly showed that the compound 4-maleate salt is crystalline in nature. In vitro antibacterial inhibition and little potential for DNA cleavage of the compound 4 were explored. We extended our study to explore the inhibition mechanism by conducting molecular docking, ADMET and molecular dynamics analysis by using Schrödinger. The molecular docking for compound 4 showed better interactions with target 3IVX with docking score of -8.508 kcal/mol with respect to standard ciprofloxacin (docking score= -3.879 kcal/mol). TML-Hydroxy was obtained in silico as non-carcinogenic and non-AMES toxic with good percent human oral absorption profile (69.639%). TML-Hydroxy showed the moderate inhibition against Mycobacteria tuberculosis with MIC 25.00 μg/mL as well as moderate inhibition against S. aureus, Bacillus sps, K. Pneumoniae and E. coli species. Conclusion: : In view of the importance of the 1,2,5-thiadiazole moiety involved, this study would pave the way for future development of more effective analogs for applications in medicinal field.

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