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Author(s):  
Hey-Ran Choi ◽  
Hong-Seuk Yang ◽  
Jae-Moon Choi ◽  
Chungon Park ◽  
Junyong In ◽  
...  

Background: Sugammadex is a specific antagonist of aminosteroidal neuromuscular blocking agents with 1:1 binding to guest molecules. Sugammadex can also bind to other drugs having a steroid component in its chemical structure. In this in vivo experiment, we investigated the differences in the recovery of rocuronium-induced neuromuscular blockade using sugammadex pre-exposed with two different concentrations of hydrocortisone.Methods: The sciatic nerves and tibialis anterior muscles of 30 adult Sprague–Dawley rats were prepared for the experiment. The sciatic nerves were stimulated using a train-of-four (TOF) pattern with indirect supramaximal stimulation at 20 s intervals. After 15 min of stabilization, a 250 μg loading dose and 125 μg booster doses of rocuronium were serially administered until > 95% depression of the first twitch tension of TOF stimulation (T1) was confirmed. The study drugs were prepared by mixing sugamadex with the same volume of three different stock solutions (0.9% normal saline, 10 mg/ml hydrocortisone, and 100 mg/ml hydrocortisone). The recovery of rats from neuromuscular blockade was monitored by assessing T1 and the TOF ratio (TOFR) simultaneously until T1 was recovered to > 95% and TOFR to > 0.9.Results: In the group injected with sugammadex premixed with a high concentration of hydrocortisone, statistically significant intergroup differences were observed in the recovery progression of T1 and TOFR (P < 0.050).Conclusions: When sugammadex was pre-exposed to a high dose of hydrocortisone only, recovery from neuromuscular blockade was delayed. Delayed recovery from neuromuscular blockade is not always plausible when sugammadex is pre-exposed to steroidal drugs.


2022 ◽  
Vol 11 (1) ◽  
pp. 11-22 ◽  
Author(s):  
Kanaka Parvathi Kannaiah ◽  
Abimanyu Sugumaran

Analyzing a drug over its overlapped spectra utilizes sophisticated instruments and more toxic solvents, which has a deleterious effect on environmental safety. There is an alarming need to develop a simple, novel, and cost-effective method for determining combined substances that are non-toxic to the environment. So, the study aimed to develop four simple, fast and eco-friendly spectrophotometric techniques for quantifying clotrimazole and tinidazole in bulk and ointment dosage form. Stock solutions produced at concentrations of 7 to 13 and 17.5 to 32.5 µg/mL of clotrimazole and tinidazole in 10% v/v ethanol and scanned in the UV-visible range 200-450 nm, and used for all methods. The methods were validated according to the International Council for Harmonization guidelines and found to be within limits. Additionally, the outliers were tested by using the Grubbers test and found within limits. Finally, green evaluation studies show that the method is more environmentally friendly, as confirmed by four assessment tools.


2021 ◽  
pp. 110037
Author(s):  
Carolina Giammei ◽  
Nedra Jouini ◽  
Marie R. Brandt ◽  
Stefanie Frey ◽  
Thomas L. Mindt ◽  
...  

Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1458
Author(s):  
Sebastián Rocha ◽  
Teresita Marzialetti ◽  
Matías Kopp ◽  
Mara Cea

5-hydroxymethylfurfural (HMF) stands out among the chemical products derived from biomass as a building block in the chemical industry. The conventional production of HMF is usually carried out from fructose, glucose, or other monosaccharides as feedstock, but sugar beet molasses, a by-product of the sugar industry containing sucrose (45–55%), is promising. This exploratory study used three aqueous stock solutions and one biphasic system as the sources of sucrose. The dehydration of sucrose to 5-hydroxymethylfurfural was assisted by microwave heating and subcritical water conditions. The maximum yield of HMF was 27.8 mol % for the aqueous solution of synthetic sucrose at 80 min of treatment. Although HMF yield was 7.1 mol % in the aqueous sugar beet molasses solution, it increased 2-fold after clarification (15.1 mol %) and 1.6-fold in the biphasic system (11.4 mol %). These are favorable outcomes since this is an exploratory investigation. The pseudo-first-order model fitted experimental data from the conversion of the sucrose from the stock solutions, and kinetic parameters were estimated and compared. The estimated reaction rate constant showed that inversion of sucrose is faster than fructose dehydration to HMF, but the latter reaction was the rate-determining step only for the biphasic system. The maximum partition coefficient value was four between 40 min and 60 min of reaction, calculated at room temperature. These predictions help investigators to estimate conversions and selectivity when pilot plants need to be simulated.


2021 ◽  
Vol 21 (2) ◽  
Author(s):  
M.P. Kavitha ◽  
P. Rajangam ◽  
M.Uma Maheswari

Field experiments were conducted to evaluate the bio efficacy and phyto toxicity of Indaziflam 500 SC in acid lime at Central Block, Horticultural College and Research Institute, Periyakulam during kharif and rabi seasons of the years 2017 and 2018. Experiments were carried out in Randomized Block Design with ten treatments and replicated thrice. Indaziflam 500 SC was sprayed as pre emergence as well as combination with post emergence herbicides in acid lime before the onset of South West Monsoon and North East Monsoon at kharif and rabi seasons respectively. Indaziflam 500 SC either alone or in combination with post emergence herbicide was completely dissolved while making stock solutions. There were no phyto toxicity symptoms on acid lime at higher doses of pre emergence application and combination with post emergence application of Indaziflam 500 SC. Pre emergence application of Indaziflam 500 SC @ 62.5 g a.i./ha recorded significantly lower no. of weed density on 30, 60, 90 and 120 DAA during both the seasons. Increased weed density was observed in untreated control at all stages of crop growth during both the seasons. Pre emergence application of Indaziflam 500 SC @ 62.5 g a.i./ha recorded significantly lower weed DMP at 90 DAA during both the seasons of the study followed by pre emergence application of Indaziflam 500 SC @ 50 g a.i./ha and resulted in higher weed control efficiency at all stages of observation. Significantly higher acid lime fruit yield of 12.45 and 13.85 t/ha was recorded with hand weeding during kharif and rabi respectively due to weed free condition maintained during entire growth stage of the crop and it was followed by pre emergence application of Indaziflam 500 SC @ 62.5 g a.i./ha.


Author(s):  
Sagar Pamu ◽  
Sazal Patyar ◽  
Lakshmi Thakkalapally

Background: Different bio-analytic methods have been developed for determining drug concentration in plasma, but methods for sitagliptin determination are still very rare. In this study, RP-HPLC based method has been developed for assessing sitagliptin concentration in plasma. Aim: To develop and validate RP-HPLC based analytical method for estimating sitagliptin in human plasma for pharmacokinetic applications. Methods: In the present study, the mobile phase composed of acetonitrile: 0.5% triethanolamine (20:80) with pH 6.5 has been utilized. Samples of plasma containing sitagliptin and internal standard (IS)-rosiglitazone were extracted with dichloromethane:diethyl ether (4:6; v/v) at pH 7.4. The rate of flow was 1 ml/min. The retention time was about 5,232 and 6,903 minutes respectively for sitagliptin and rosiglitazone. Results: At concentrations of 100-3200 ng/ml in plasma, calibration curves of sitagliptin were linear. The inter- and intra-day precision and accuracy ranged in between 93.56-98.56% and 1.09-4.55% respectively. For specificity, the study findings showed no co-eluting peaks occurring with IS drug (rosiglitazone) and confirmed that no percentage of interferences at analyte (sitagliptin) retention in presence of rosiglitazone. The sitagliptin recovery was 96.442%. Chromatographic separations were performed on HI Qsil C-18 HS column (250mm x 4.6mm x 5μm). The stability of stock solutions of sitagliptin and IS at room temperature was 98.06% and 100.79% respectively while under refrigerated conditions stability was 98.19% and 96.59% respectively. Freeze-thaw stability for sitagliptin was performed with low & high QC and shown as 98.26% for and 97.45% respectively. The limits of detection and quantification were 8.592 ng/ml and 28.641 ng/ml respectively. Conclusion: A simple, sensitive and accurate method was developed for bio analytical estimation of sitagliptin in human plasma using liquid-liquid extraction technique. The validation results of linearity, accuracy, precision, stability, selectivity, ruggedness, LOD and LOQ were good under acceptable limit and can be applied for pharmacokinetic studies.


2021 ◽  
Author(s):  
Kasim Roba Jilo

Abstract Background Ethiopia is one of the plant species-rich countries in the world and the center of origin of many medicinal plants. Studying antimicrobial activities of pollen is vivacious to investigate plant resources for medicinal values and the study was conducted to evaluate antimicrobial properties of bee pollen against mentioned bacteria. Methods Completely Randomized Design was used for laboratory work. After adjusting turbidity, consistent growth of bacterial culture was made using a sterilized cotton swab. 20 grams of bee pollen was added to 200 ml of distilled water as well as ethanol and finally, the extract was filtered by Whatman filter by paper, dried and weighted and stock solutions were made as follows,3.6 gm. was added to 12 ml of distilled water to prepare stock solutions as follows 3.6:12 = 0.3 x \({10}^{6}\) = 3 x \({10}^{5}\) ppm stock solution and antimicrobial activities of pollen were tested against mentioned bacteria. Data were imported to R software version 3.44. Multilevel analysis was used to see the interaction between bacteria species and each concentration of pollen and Anova was used to see the significance of these concentrations on bacteria species. A p-value of < 0.05 was considered statistically significant. Results Results indicated that bacteria were more inhibited at 72 hours than 48 and 24 hours and the results showed an ethanolic extract of bee pollen had antimicrobial activities against both Gram-negative and Gram-positive bacteria mentioned above. Time has significant effects on tested bacteria (p = 0.000) and treatments have significant effects on tested organisms (p = 0.000). The ethanolic extract inhibited the growth of more Gram-negative bacteria: Escherichia coli and Shigella boydii. Bacillus subtilis was mostly inhibited by aqueous extract of bee pollen than others. Conclusions Ethanolic extract of pollen had antibacterial activities against all tested bacterial strains even though it is concentration and time-based. The ethanolic extract inhibited more Gram-negative bacteria relatively while aqueous extract inhibited more Gram-positive relatively. Negative controls (sterilized water) didn’t show any antimicrobial properties, while positive control (Chloramphenicol) had antimicrobial activities. Further isolation and characterization of bioactive compounds from pollen are useful to develop a novel botanical formulation for further applications from the pollen of medicinal plants.


Author(s):  
Kedar Tejashree R. ◽  
A.R. Dashetwar ◽  
D.P. Kardile ◽  
A.P. Jadhav ◽  
V.C. Bhagat ◽  
...  

A new, simple, accurate, precise and reproducible UV-Spectrophotometric method is being developed for the simultaneous estimation of Metformin Hydrochloride and Voglibose in tablet dosage form. The stock solutions were prepared in methanol. The λmax for Metformin Hydrochloride and Voglibose were found to be248 nm and 287nm respectively. The Metformin Hydrochloride and Voglibose obeyed Beer’s law in concentration range of 8-16µg/ml and 4-20µg/ml respectively. Results of analysis of absorbance ratio method were analysed and validated for various parameters according to ICH guidelines for accuracy, precision, linearity, robustness, LOD and LOQ. The proposed method is highly sensitive, precise and accurate, therefore can be used for intended purpose.


2021 ◽  
Author(s):  
Kevin Aumiller ◽  
Eric Stevens ◽  
Robert Scheffler ◽  
Zehra Tuzun Guvener ◽  
Emily Tung ◽  
...  

Lactobacilli and acetobacters are commercially important bacteria that often form communities in natural fermentations, including food preparations, spoilage, and in the digestive tract of Drosophila melanogaster fruit flies. Communities of these bacteria are widespread and prolific, despite numerous strain-specific auxotrophies, suggesting they have evolved nutrient interdependencies that regulate their growths. The use of a chemically-defined medium (CDM) supporting the growth of both groups of bacteria would greatly facilitate identification of the precise metabolic interactions between these two groups of bacteria. While numerous such media have been developed that support specific strains of lactobacilli and acetobacters, there has not been a medium formulated to support both genera. We developed such a medium, based on a previous Lactobacillus CDM, by modifying the nutrient abundances to improve growth of both groups of bacteria. We further simplified the medium by substituting casamino acids for individual amino acids and the standard Wolfe's vitamins and mineral stocks for individual vitamins and minerals, resulting in a reduction from 40 to 8 stock solutions. The new CDM and variations of it support robust growth of lactobacilli and acetobacters. We provide the composition and an example of its use to measure nutritional interactions.


Author(s):  
Andrew Biedermann ◽  
Isabella Gengaro ◽  
Sergio Rodriguez ◽  
Kerry Love ◽  
John Love

Developing media to sustain cell growth and production is an essential and ongoing activity in bioprocess development. Modifications to media can often address host or product-specific challenges, such as low productivity or poor product quality. For other applications, systematic design of new media can facilitate the adoption of new industrially relevant alternative hosts. Despite manifold existing methods, common approaches for optimization often remain time and labor intensive. We present here a novel approach to conventional media blending that leverages stable, simple, concentrated stock solutions to enable rapid improvement of measurable phenotypes of interest. We applied this modular methodology to generate high-performing media for two phenotypes of interest: biomass accumulation and heterologous protein production, using high-throughput, milliliter-scale batch fermentations of Pichia pastoris as a model system. In addition to these examples, we also created a flexible open-source package for modular blending automation on a low-cost liquid handling system to facilitate wide use of this method. Our modular blending method enables rapid, flexible media development, requiring minimal labor investment and prior knowledge of the host organism, and should enable developing improved media for other hosts and phenotypes of interest.


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