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

2020 ◽  
Vol 11 (SPL4) ◽  
pp. 2499-2515
Author(s):  
Nabil Abdullah ◽  
Amit B Patil
Keyword(s):  
Factorial Design ◽  
Drying Time ◽  
Flexible Film ◽  
Pharmaceutical Industries ◽  
Model Drug ◽  
32 Factorial Design ◽  
Spray Formulation ◽  
Experimental Values ◽  
The Relationship

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.

Profile Imaging of Silicon Surface Reconstructions

1985 ◽  
Vol 43 ◽  
pp. 262-263
Author(s):  
O.L. Krivanek ◽  
G.J. Wood
Keyword(s):  
Electron Microscopy ◽  
Surface Structure ◽  
Structure Determination ◽  
Silicon Surface ◽  
Good Resolution ◽  
Surface Reconstructions ◽  
Bulk Structure ◽  
Point To Point ◽  
The Relationship

Electron microscopy at 0.2nm point-to-point resolution, 10-10 torr specimei region vacuum and facilities for in-situ specimen cleaning presents intere; ing possibilities for surface structure determination. Three methods for examining the surfaces are available: reflection (REM), transmission (TEM) and profile imaging. Profile imaging is particularly useful because it giv good resolution perpendicular as well as parallel to the surface, and can therefore be used to determine the relationship between the surface and the bulk structure.

A combined ultrastructural and gene molecular research for the relationship between human uterine cervical carcinoma and human papillomavirus

1990 ◽  
Vol 48 (3) ◽  
pp. 204-205
Author(s):  
Kun Lee ◽  
Jingyi Si ◽  
Ricai Han ◽  
Wei Zhang ◽  
Bingbing Tan ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Human Papillomavirus ◽  
Intraepithelial Neoplasia ◽  
Hpv Infection ◽  
Dot Blot ◽  
Homologous Sequences ◽  
Normal Cervical Epithelium ◽  
The Relationship ◽  
Chronic Cervicitis

There are more supports for the view that human papillomavirus (HPV) infection might be an etiological factor in the development of cervical cancer when the association of persistent condylomata is considered. Biopsies from 318 cases with squamous cell carcinoma of uterine cervix, 48 with cervical and vulvar condylomata, 14 with cervical intraepithelial neoplasia (CIN), 34 with chronic cervicitis and 24 normal cervical epithelium were collected from 5 geographic regions of China with different cervical cancer mortalities. All specimens were prepared for Dot blot, Southern blot and in situ DNA-DNA hybridizations by using HPV-11, 16, 18 DNA labelled with 32P and 3H as probes to detect viral homologous sequences in samples. Among them, 32 cases with cervical cancer, 27 with condyloma and 10 normal cervical epitheliums were randomly chosen for comparative EM observation. The results showed that: 1), 192 out of 318 (60.4%) cases of cervical cancer were positive for HPV-16 DNA probe (Table I)

3 (2) Factorial Design Assisted Crushed Puffed Rice-HPMC-Chitosan based Hydrodynamically Balanced System of Metoprolol Succinate

2020 ◽  
Vol 10 (3) ◽  
pp. 237-249
Author(s):  
Shashank Soni ◽  
Veerma Ram ◽  
Anurag Verma
Keyword(s):  
Drug Release ◽  
Factorial Design ◽  
Hydroxypropyl Methylcellulose ◽  
Batch Size ◽  
Metoprolol Succinate ◽  
Zero Order Kinetics ◽  
Two Factors ◽  
Puffed Rice ◽  
Model Drug

Introduction: Hydrodynamically balanced system (HBS) possesses prolonged and continuous delivery of the drug to the gastrointestinal tract which improves the rate and extent of medications that have a narrow absorption window. The objective of this work was to develop a Hydrodynamically Balanced System (HBS) of Metoprolol Succinate (MS) as a model drug for sustained stomach specific delivery. Materials and Methods: Experimental batches were designed according to 3(2) Taguchi factorial design. A total of 9 batches were prepared for batch size 100 capsules each. Formulations were prepared by physically blending MS with polymers followed by encapsulation into hard gelatin capsule shell of size 0. Polymers used were Low Molecular Weight Chitosan (LMWCH), Crushed Puffed Rice (CPR), and Hydroxypropyl Methylcellulose K15 M (HPMC K15M). Two factors used were buoyancy time (Y1) and time taken for 60% drug release (T60%; Y2). Results: The drug excipient interaction studies were performed by the thermal analysis method which depicts that no drug excipient interaction occurs. In vitro buoyancy studies and drug release studies revealed the efficacy of HBS to remain gastro retentive for a prolonged period and concurrently sustained the release of MS in highly acidic medium. All formulations followed zero-order kinetics. Conclusion: Developed HBS of MS with hydrogel-forming polymers could be an ideal delivery system for sustained stomach specific delivery and would be useful for the cardiac patients where the prolonged therapeutic action is required.

scholarly journals Novel hydrogen chemisorption properties of amorphous ceramic compounds consisting of p-block elements: exploring Lewis acid-base Al–N pair site formed in-situ within polymer-derived silicon-aluminum-nitrogen-based system

2021 ◽  
Author(s):  
Shotaro Tada ◽  
Norifumi Asakuma ◽  
Shiori Ando ◽  
Toru Asaka ◽  
Yusuke Daiko ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Active Site ◽  
Hydrogen Chemisorption ◽  
Acid Base ◽  
Polymer Derived Ceramics ◽  
System P ◽  
Ceramic Compounds ◽  
The Relationship

This paper reports on the relationship between the H2 chemisorption properties and reversible structural reorientation of the possible active site around Al formed in-situ within polymer-derived ceramics (PDCs) based on...

scholarly journals Comparison of the Concentration of Risk Elements in Alluvial Soils Determined by pXRF In Situ, in the Laboratory, and by ICP-OES

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 938
Author(s):  
Ladislav Menšík ◽  
Lukáš Hlisnikovský ◽  
Pavel Nerušil ◽  
Eva Kunzová
Keyword(s):  
Precision Agriculture ◽  
Alluvial Soil ◽  
Coefficient Of Determination ◽  
Fast Method ◽  
Agricultural Practice ◽  
Regression Equations ◽  
Icp Oes ◽  
Risk Elements ◽  
The Relationship

The aim of the study was to compare the concentrations of risk elements (As, Cu, Mn, Ni, Pb, Zn) in alluvial soil, which were measured by a portable X-ray fluorescence analyser (pXRF) in situ (FIELD) and in the laboratory (LABORATORY). Subsequently, regression equations were developed for individual elements through the method of construction of the regression model, which compare the results of pXRF with classical laboratory analysis (ICP-OES). The accuracy of the measurement, expressed by the coefficient of determination (R2), was as follows in the case of FIELD–ICP-OES: Pb (0.96), Zn (0.92), As (0.72), Mn (0.63), Cu (0.31) and Ni (0.01). In the case of LABORATORY–ICP-OES, the coefficients had values: Pb (0.99), Zn (0.98), Cu and Mn (0.89), As (0.88), Ni (0.81). A higher dependence of the relationship was recorded between LABORATORY–ICP-OES than between FIELD–ICP-OES. An excellent relationship was recorded for the elements Pb and Zn, both for FIELD and LABORATORY (R2 higher than 0.90). The elements Cu, Mn and As have a worse tightness in the relationship; however, the results of the model have shown its applicability for common use, e.g., in agricultural practice or in monitoring the quality of the environment. Based on our results, we can say that pXRF instruments can provide highly accurate results for the concentration of risk elements in the soil in real time for some elements and meet the principle of precision agriculture: an efficient, accurate and fast method of analysis.

scholarly journals The Influence of Temperature and Viscosity of Polyethylene Glycol on the Rate of Microwave-Induced In Situ Amorphization of Celecoxib

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 110
Author(s):  
Nele-Johanna Hempel ◽  
Tra Dao ◽  
Matthias M. Knopp ◽  
Ragna Berthelsen ◽  
Korbinian Löbmann
Keyword(s):  
Polyethylene Glycol ◽  
Microwave Radiation ◽  
Magnesium Stearate ◽  
Einstein Equations ◽  
Dissolution Process ◽  
Target Temperature ◽  
Peg 4000 ◽  
Lower Viscosity ◽  
Model Drug

Microwaved-induced in situ amorphization of a drug in a polymer has been suggested to follow a dissolution process, with the drug dissolving into the mobile polymer at temperatures above the glass transition temperature (Tg) of the polymer. Thus, based on the Noyes–Whitney and the Stoke–Einstein equations, the temperature and the viscosity are expected to directly impact the rate and degree of drug amorphization. By investigating two different viscosity grades of polyethylene glycol (PEG), i.e., PEG 3000 and PEG 4000, and controlling the temperature of the microwave oven, it was possible to study the influence of both, temperature and viscosity, on the in situ amorphization of the model drug celecoxib (CCX) during exposure to microwave radiation. In this study, compacts containing 30 wt% CCX, 69 wt% PEG 3000 or PEG 4000 and 1 wt% lubricant (magnesium stearate) were exposed to microwave radiation at (i) a target temperature, or (ii) a target viscosity. It was found that at the target temperature, compacts containing PEG 3000 displayed a faster rate of amorphization as compared to compacts containing PEG 4000, due to the lower viscosity of PEG 3000 compared to PEG 4000. Furthermore, at the target viscosity, which was achieved by setting different temperatures for compacts containing PEG 3000 and PEG 4000, respectively, the compacts containing PEG 3000 displayed a slower rate of amorphization, due to a lower target temperature, than compacts containing PEG 4000. In conclusion, with lower viscosity of the polymer, at temperatures above its Tg, and with higher temperatures, both increasing the diffusion coefficient of the drug into the polymer, the rate of amorphization was increased allowing a faster in situ amorphization during exposure to microwave radiation. Hereby, the theory that the microwave-induced in situ amorphization process can be described as a dissolution process of the drug into the polymer, at temperatures above the Tg, is further strengthened.

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