Mercury Accumulation in Commercial Varieties of Oryza sativa L. Cultivated in Soils of La Mojana Region, Colombia

The Hg accumulation in different commercial varieties of Oryza sativa L. was evaluated in the region of La Mojana, Colombia, where rice cultivation has become the staple food of the population living in this area. The varieties studied were Fedearroz-473 (FA473), Fedearroz-2000 (FA2000), and Fedearroz-Mocari (FAM). Soil spiked at different Hg levels was evaluated, (130, 800, and 1500 µg kg−1) using a 32 factorial design that consisted of 3 (rice varieties) × 3 (Hg contents). The biomass, 1000-grain weight, and the accumulation of Hg in the roots, grains, and husks were determined. The highest biomass was found in the FA473 (308.76 ± 108.26 g), and the lowest was found in FAM (144.04 ± 26.45 g) in the 1500 µg kg−1 Hg soil in both cases. The weight per 1000-grains decreased significantly in the soil containing 800 µg of Hg kg−1. Hg accumulation in the organs of the evaluated varieties was higher in the roots, followed by in the husks and grains. The Hg in the rice grains of the evaluated varieties presented levels close to the permissible limit of the Chinese standard (20 μg Hg kg−1) in the evaluated soils and were only exceeded by FA473. Although in natural soil concentrations, the non-cancer health risk (HQ) from rice consumption was lower for FA473 and FAM; Hg enrichment in the soil of La Mojana region may endanger the health of future populations due to their high consumption of rice.

Mono- and Dicationic DABCO/Quinuclidine Composed Nanomaterials for the Loading of Steroidal Drug: 32 Factorial Design and Physicochemical Characterization

Oil-in-water nanoemulsions (NEs) are considered a suitable nanotechnological approach to improve the eye-related bioavailability of lipophilic drugs. The potential of cationic NEs is prominent due to the electrostatic interaction that occurs between the positively charged droplets with the negatively charged mucins present in the tear film. This interaction offers prolonged NEs residence at the ocular surface, increasing the drug absorption. Triamcinolone acetonide (TA) is one of the first pharmacologic strategies applied as an intravitreal injection in the treatment of age-related macular degeneration (AMD). Newly synthesized quaternary derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO) and quinuclidine surfactants have been screened with the purpose to select the best compound to formulate long-term stable NEs that combine the best physicochemical properties for the loading of TA intended for ocular administration.

Development of gastroretentiv floating tablets of losartan potassium by sublimation method

The purpose of present study was to formulate and Evaluate Sustained release floating tablet of losartan Potassium using Camphor and Polyethylene Oxide as Pore formation for floating and release retarding agent respectively to improve gastric residence time and patient compliance in management of hypertension. The tablet was prepared by direct compression by using HPMC K4 as dry binder. Camphor and PEO as floating and release retarding agent for sustained release floating tablet. Post compression was done to increase the hardness and floating time of tablet. Release modifier was used to speed up the release of drug from sustained release floating tablet. The effect of two independent variables like amount of Sublimating agent (camphor) and amount of Polyethylene oxide (PEO) on Q30min, Q360min, and Q720min was optimized using 32 factorial design and analyzed using the software design expert 10.0.3. The observed (actual values) responses were coincided well with the predicted values, given by the optimization technique. The floating tablet were characterized by FTIR for drug excipient compatibility.

Formulation Development and Evaluation of Mouth Dissolving Tablet of Aspirin by Using QbD Approach

In the current investigations, mouth dissolving tablets (MDT) were developed by applying quality by design (QbD) approach. Direct compression method was applied for the preparation of MDT containing aspirin using 32 factorial design with quantity of drug, microcrystalline cellulose (MCC) and crosscarmellose sodium (CCS) as dependant variables. MCC and CCS were used as superdisintegrants. Sodium stearyl fumarate was used as lubricant. Developed MDT were evaluated for characteristics like hardness, friability, disintegration time (DT) and in vitro drug release . Design Expert 11.0 described adequately impact of selected variables (MCC and CCS) at various levels for response under study (DT and friability). The optimized batch showed disintegration time of 15-28 secs, friability within 1% and in vitro drug release of 75-98% after 30 mins, respectively. The present study of experimental design revealed that MCC and CCS are fruitful at low concentration to develop the optimized formulation. As per the results obtained from the experiments, it can be concluded that QbD is an effective and efficient approach for the development of quality into MDT with the application of QTPP, risk assessment and critical quality attributes (CQA). Dhaka Univ. J. Pharm. Sci. 20(1): 19-29, 2021 (June)

Quality by Design for Development, Optimization and Characterization of Brucine Ethosomal Gel for Skin Cancer Delivery

Natural products have been extensively used for treating a wide variety of disorders. In recent times, Brucine (BRU) as one of the natural medications extracted from seeds of nux vomica, was investigated for its anticancer activity. As far as we know, this is the first study on BRU anticancer activity against skin cancer. Thus, the rational of this work was implemented to develop, optimize and characterize the anticancer activity of BRU loaded ethosomal gel. Basically, thin film hydration method was used to formulate BRU ethosomal preparations, by means of Central composite design (CCD), which were operated to construct (32) factorial design. Two independent variables were designated (phospholipid percentage and ethanol percentage) with three responses (vesicular size, encapsulation efficiency and flux). Based on the desirability function, one formula was selected and incorporated into HPMC gel base to develop BRU loaded ethosomal gel. The fabricated gel was assessed for all physical characterization. In-vitro release investigation, ex-vivo permeation and MTT calorimetric assay were performed. BRU loaded ethosomal gel exhibited acceptable values for the characterization parameters which stand proper for topical application. In-vitro release investigation was efficiently prolonged for 6 h. The flux from BRU loaded ethosome was enhanced screening optimum SSTF value. Finally, in-vitro cytotoxicity study proved that BRU loaded ethosomal gel significantly improved the anticancer activity of the drug against A375 human melanoma cell lines. Substantially, the investigation proposed a strong motivation for further study of the lately developed BRU loaded ethosomal gel as a prospective therapeutic strategy for melanoma treatment.

Formulation and Evaluation of Sustained Release Ibuprofen Matrix Tablets Using Starch from Maize Genotypes as Polymer

Objective: Maize plants have been genetically engineered to produce genotypes with agriculturally desirable traits such as high starch content, pest resistance and increased nutritional value. Maize starch has been widely used as an excipient in pharmaceutical formulations. This study aims to produce sustained release ibuprofen tablets using starch obtained from different maize genotypes as polymers. Methods: Ibuprofen matrix tablets were prepared with the starches isolated from the maize genotypes and the unmodified plant. The mechanical properties of the tablets were evaluated using the crushing strength (CS), friability (FR) and CSFR. A 32 factorial design was applied using the time taken for 50 % (T50) and 90 % (T90) drug release as dependent variables while the polymer-drug ratio and polymer types were the independent variables. Results: The CSFR was significantly higher (p<0.05) in tablets formulated with the starches obtained from the modified cultivars. Drug release for all the formulations fitted the Higuchi model while the mechanism of release was generally by super case transport. The polymer-drug ratio and polymer type strongly interacted to increase the dissolution times (T50 and T90) and CSFR. Starches isolated from the genetically modified cultivars provided a more sustained release of ibuprofen from the tablet matrix through erosion and polymer relaxation. Conclusion: The results indicate that the genetic modification of maize can quantitatively affect the drug release modifying effects of maize starch in drug formulation.

Lipid Nanoparticles Loaded with Iridoid Glycosides: Development and Optimization Using Experimental Factorial Design

Lipid nanoparticles based on multiple emulsion (W/O/W) systems are suitable for incorporating hydrophilic active substances, including iridoid glycosides. This study involved optimization of composition of lipid nanoparticles, incorporation of active compounds (aucubin and catalpol), evaluation of stability of the resulting nanocarriers, and characterization of their lipid matrix. Based on 32 factorial design, an optimized dispersion of lipid nanoparticles (solid lipid:surfactant—4.5:1.0 wt.%) was developed, predisposed for the incorporation of iridoid glycosides by emulsification-sonication method. The encapsulation efficiency of the active substances was determined at nearly 90% (aucubin) and 77% (catalpol). Regarding the stability study, room temperature was found to be the most suitable for maintaining the expected physicochemical parameter values (particle size < 100 nm; polydispersity index < 0.3; zeta potential > |± 30 mV|). Characterization of the lipid matrix confirmed the nanometer size range of the resulting carriers (below 100 nm), as well as the presence of the lipid in the stable β’ form.

Formulation development and characterization of in-situ gel of Rizatriptan Benzoate for intranasal delivery

The present investigation was aimed to formulate and characterize ion-activated in-situ gel loaded with Rizatriptan Benzoate (RIZ) for intranasal administration for brain targeting. The gel was further optimized for process and formulation parameters by using 32 factorial design. The optimized batch having the concentrations of gellan gum and HPMC E15 LV 33.83 mg and 9.6 mg respectively. Gel strength and mucoadhesive strength of the optimized formulation were found to be 32.54 sec and 2580.50 dynes/cm2 respectively. Moreover, improved in-vitro and ex-vivo release profile of in-situ gel were observed in comparison to drug solution. In a nutshell, the developed formulation holds a great promise in overcoming the limitation associated with currently marketed RIZ formulations and illustrates the potential use of ion-activated in-situ gel to administer the drug by nasal route for brain targeting. Keywords: In-situ gel, Rizatriptan benzoate, Ion-activated, Gellan gum, HPMC E15 LV, Brain delivery, Migraine

Application of DoE in polymers screening and optimization of in situ topical ϑilm-forming solution for spray formulation

DoE is a structured and organised method to determine the relationship between the effect of change in the concentration of the independent variables and its impact on the formulation, through establishing a mathematical model. Since the acceptance of the QbD approach by the regulatory authorities across the world, DoE has been widely implemented in the areas of screening and optimisation of the formulations by the pharmaceutical industries. The topical delivery of API still posses' limitations such as insufficient contact time, odd hours of application time, sticking to fabrics, formulation washing off, etc. To address these limitations, the researcher planned to develop an in situ polymeric sprays that will form a transparent and flexible film, & will not interfere with the applicant's routine. Polymers such as HPMC, Eudragit RS100, PVP K30, PVP K90, Carbopol, Propylene glycol, Soluplus, and pullulan whereas the plasticisers selected were sorbitol. Voriconazole, a second-generation triazole, was used as a model drug. The article is a technological demonstration, in which the screening of polymers as well as the optimised concentration of the polymeric will be selected through 32 factorial design. The aim of the present article is also to establish the relationship between the software response and experimental values. The experiments were designed using 32 factorial design which resulted in 9 trial runs. Each run was evaluated for drying time, viscosity, and stickiness. The resultant response surface Later the optimisation, to yield an optimised polymeric solution that can deliver a desired in situ films. Based on ANOVA comparison of variability due to treatment, the significance of the regression model was evaluated. Other procedures such as DSC, FRIR, Stickiness, pH, diffusion studies were also performed on the selected formulation.