scholarly journals The influence factors of mean particle size and positive quality control of bacterial filtration efficiency system

2021 ◽  
Author(s):  
Yayi Yi

Summary Background The Coronavirus Disease 2019 (COVID-19) has swept the whole world with high mortality. Since aerosol transmission is the main route of transmission, wearing a mask serves as a crucial preventive measure. An important parameter to evaluate the performance of a mask is the bacteria filtration efficiency (BFE). Aerosol mean particle size (MPS) and positive quality control value are two key indexes of BFE system. Aim To study the major influence factors of the mean particle size of bacterial aerosols and positive quality control value of BFE system. Method and Results In this study, we investigated the influence of Anderson sampler, spray flow, medium thickness, and peristaltic pump flow on the MPS of bacterial aerosols and positive quality control value of BFE system, respectively. The results show that the machining accuracy of Anderson sampler has great influence on aerosol MPS and positive quality control value. With the increase of aerosol spray flow rate, the positive quality control value will increase gradually, but the effect on aerosol MPS is not a simple linear relationship. As the agar medium thickness increased, the positive quality control value and aerosol MPS increased gradually. With the increase of peristaltic pump flow, the positive quality control value increased gradually, while the aerosol MPS was basically in a downward trend. When the peristatic pump flow rate was 0.1mL/min, the spray flow rate was 7.2L/min, the agar plate thickness was 27mL, and the Anderson sampler of Beijing Mingjie was used for the experiment, the aerosol MPS and positive quality control value were both within the acceptable range and were the optimal parameters. Conclusions This study provides guidance for the manufacturers of the BFE system and improves the protective performance of masks, which is important for the human health, especially during the occurrence of viral pandemics such as "COVID-19".

Author(s):  
Kalleshvar P. Jatte ◽  
R. D. Chakole ◽  
M. S. Charde

RP-HPLC method was developed for the estimation of Lisinopril and Hydrochlorothiazide in tablet dosage form with the help of Quality by Design (QbD) approaches. In this method concentration of each drug was obtained by using the absorptivity values calculated for drug wavelength 226.0 nm and solving the equation. The RP-HPLC method was performed C18-(100mm x 4.6 mm,)2.5 μm particle size in gradient mode, and the sample was analysed using methanol 45.0 ml and 55.0 ml (pH 3.3 0.05% OPA with TEA) as a mobile phase at a flow rate of 0.8 ml/min and detection at nm. By the retention time for Lisinopril and Hydrochlorothiazide found 3.39 and 4.59 min respectively. Validation related the method is specific, rapid, accurate, precise, reliable, and reproducible. Calibration plots by both HPLC were linear over the 5-25 and 12.5-62.5 μg/ml for Lisinopril and Hydrochlorothiazide respectively, and recoveries from tablet dosage form were between 99.02 and 100.00 %. The method can be used for routine of the quality control in pharmaceuticals. The degradation profiling of Lisinopril and Hydrochlorothiazide were also carried out.


1986 ◽  
Vol 64 (6) ◽  
pp. 1331-1336 ◽  
Author(s):  
Hugh R. MacCrimmon ◽  
Barra L. Gots

Effects of various loadings of a test gravel incubation substrate (32- to >4-mm pebble) with a single sediment mix (<0.25- to 4-mm sand) were examined in vertical flow incubators at a constant temperature (9.9 °C) and flow rate (200 mL min−1). Mean survival (75%) from ova burial to juvenile emergence was not influenced significantly by different sediment loadings. However, time to first and median emergence, duration of emergence, stage of development at emergence, and within-substrate behaviour were each correlated positively with mean particle size (r ≥ 0.72) and negatively with sediment loading rates (r ≥ −0.68).


2018 ◽  
Vol 14 (1) ◽  
pp. 31-60 ◽  
Author(s):  
M. Y. Guida ◽  
F. E. Laghchioua ◽  
A. Hannioui

This article deals with fast pyrolysis of brown algae, such as Bifurcaria Bifurcata at the range of temperature 300–800 °C in a stainless steel tubular reactor. After a literature review on algae and its importance in renewable sector, a case study was done on pyrolysis of brown algae especially, Bifurcaria Bifurcata. The aim was to experimentally investigate how the temperature, the particle size, the nitrogen flow rate (N2) and the heating rate affect bio-oil, bio-char and gaseous products. These parameters were varied in the ranges of 5–50 °C/min, below 0.2–1 mm and 20–200 mL. min–1, respectively. The maximum bio-oil yield of 41.3wt% was obtained at a pyrolysis temperature of 600 °C, particle size between 0.2–0.5 mm, nitrogen flow rate (N2) of 100 mL. min–1 and heating rate of 5 °C/min. Liquid product obtained under the most suitable and optimal condition was characterized by elemental analysis, 1H-NMR, FT-IR and GC-MS. The analysis of bio-oil showed that bio-oil from Bifurcaria Bifurcata could be a potential source of renewable fuel production and value added chemicals.


Author(s):  
Nisha Patel ◽  
Hitesh A Patel

In this study, we sought to improve the dissolution characteristics of a poorly water-soluble BCS class IV drug canaglifozin, by preparing nanosuspension using media milling method. A Plackett–Burman screening design was employed to screen the significant formulation and process variables. A total of 12 experiment were generated by design expert trial version 12 for screening 5 independent variables namely the amount of stabilizer in mg (X1), stirring time in hr (X2), amt of Zirconium oxide beads in gm (X3), amount of drug in mg (X4) and stirring speed in rpm (X5) while mean particle size in nm (Y1) and drug release in 10 min. were selected as the response variables. All the regression models yielded a good fit with high determination coefficient and F value. The Pareto chart depicted that all the independent variables except the amount of canaglifozin had a significant effect (p<0.001) on the response variables. The mathematical model for mean particle size generated from the regression analysis was given by mean particle size = +636.48889 -1.28267 amt of stabilizer(X1) -4.20417 stirring time (X2) -7.58333 amt of ZrO2 beads(X3) -0.105556 amt of drug(X4) -0.245167 stirring speed(X5) (R2=0.9484, F ratio=22.07, p<0.001). Prepared canaglifozin nanosuspension exemplified a significant improvement (p<0.05) in the release as compared to pure canaglifozin and marketed tablet with the optimum formulation releasing almost 80% drug within first 10min. Optimized nanosuspension showed spherical shape with surface oriented stabilizer molecules and a mean particle diameter of 120.5 nm. There was no change in crystalline nature after formulation and it was found to be chemically stable with high drug content.


2020 ◽  
Vol 71 (1) ◽  
pp. 1-12
Author(s):  
Salman H. Abbas ◽  
Younis M. Younis ◽  
Mohammed K. Hussain ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor ◽  
...  

The biosorption performance of both batch and liquid-solid fluidized bed operations of dead fungal biomass type (Agaricusbisporus ) for removal of methylene blue from aqueous solution was investigated. In batch system, the adsorption capacity and removal efficiency of dead fungal biomass were evaluated. In fluidized bed system, the experiments were conducted to study the effects of important parameters such as particle size (701-1400�m), initial dye concentration(10-100 mg/L), bed depth (5-15 cm) and solution flow rate (5-20 ml/min) on breakthrough curves. In batch method, the experimental data was modeled using several models (Langmuir,Freundlich, Temkin and Dubinin-Radushkviechmodels) to study equilibrium isotherms, the experimental data followed Langmuir model and the results showed that the maximum adsorption capacity obtained was (28.90, 24.15, 21.23 mg/g) at mean particle size (0.786, 0.935, 1.280 mm) respectively. In Fluidized-bed method, the results show that the total ion uptake and the overall capacity will be decreased with increasing flow rate and increased with increasing initial concentrations, bed depth and decreasing particle size.


2020 ◽  
Vol 17 (1) ◽  
pp. 172-183
Author(s):  
Nandanwadkar Shrikrishna Madhukar Hema ◽  
Mastiholimath Vinayak Shivamurthy ◽  
Pulija Karunakar

Introduction: Capsaicin (8-methy-N-vanillyl-6-nonenamide), a potential analgesic derived from Capsicum annuum (Chili peppers), widely used from ancient times for its pharmacological activities such as anti-inflammatory, anti-oxidant and analgesic and provides relief from migraine and diabetes. But for obvious reasons, capsaicin cannot be administered directly. The present work was designed with a focus to comply with mandatory requirement in various pharmacopeias to know the actual content of API present in final formulations. The formulation (TS3) consisting of 3% lipid, with 4:6 ratio of the polymer and solvent, was found to be the optimized formulation, which gave the best evaluation with regard to the particle size (97.03±2.68) nm, polydispersity index (0.20±0.00), higher zeta potential (61.28±2.06) mv, morphological studies and highest drug entrapment efficiency (68.34±4.24)%. The prepared transferosome formulation was subjected to characterization by validated HP-TLC method consisting of N-Hexane: Tert- Iso-butyl-methyl ether in ratio (5:15) v/v. Linearity was performed in the range of 50-1500 ng/spot with LOD/LOQ 50 ng and 150 ng, with regression analysis (R) of 99.91%. Recovery analysis was performed at 3 different levels at 80, 100 and 120 with an average recovery of 106.97%, respectively. Till now, no analytical method has been reported, associated with the characterization of pharmaceutical nano-forms (Capsaicin), like transferosomes. Thus, the maiden validated HP-TLC method for concurrent analysis of capsaicin as API in nano-transferosome may be employed in process quality control of formulations containing the said API. Background: The irritability and adverse effects post application, leading to inflammation and neural pain at the site of administration of newly Capsaicin API and its chemical entities and marketed formulations are usually related to poor permeability, leading to drug complex reactions in the development phases or therapeutic failure along with the quantification of the same in blood plasma. However, advancement in drug formulations with the use of polymer: alcohol ratio and modernized analytical techniques for the quantification of Pharmaceutical APIs seems to be emerging and promising for overcoming pain and related inflammatory complications by formulating the APIs in Transferosome formulation with Validated HP-TLC technique being used as an effective economic and precise tool for quantitative analysis of APIs in their respective nano-forms. Objective: The study proposes a novel standardized method development and validation of pharmaceutical nanoforms with Capsaicin as API. Method: Capsaicin Transferosomes were formulated using Ultra probe sonication by utilizing different proportions of phospholipid 90G dissolved in a mixture of ethanol and propylene glycol. The formulation was subjected to Dynamic Light Scattering (DLS) technique for nano-particle analysis followed by characterization with respect to particle size, polydispersity index, zeta potential and entrapment efficiency. The morphological study of vesicles was determined using SEM and TEM. A Validated HP-TLC method for the identification and determination of Capsaicin in transferosomes formulation was performed as per the ICH guidelines. Results: The formulation gave the best evaluation for particle size (97.03±2.68) nm, polydispersity index (0.20±0.00), higher zeta potential (61.28±2.06) mv, morphological studies (SEM & TEM) and highest drug entrapment efficiency (68.34±4.24)%. DSC thermograms and FTIR spectral patterns confirmed no physical interaction by polymers with API. The prepared formulation was then characterized using HP-TLC method. The best resolution was found in NHexane: Tert-Isobutyl methyl ether in a ratio of 5:15 v/v. The Rf was found to be 0.3±0.03. Linearity was performed in a range of 50-1500 ng/spot, with regression analysis (R) of 99.91% Further, recovery analysis was done at 3 different levels as 80, 100 and 120 with an average recovery of 106.97%. The LOD/LOQ was found to be 50 and 150 ng, respectively. Precision was carried out in which % RSD was found to be precise and accurate. Conclusion: The outcomes of the present study suggested that the proposed novel formulation analyzed by Validated planar chromatographic technique (HP-TLC) for Capsaicin quantification in nanoforms may be employed as a routine quality control method for the said API in various other formulations.


2005 ◽  
Vol 155 (1) ◽  
pp. 85-91 ◽  
Author(s):  
N. Etxebarria ◽  
G. Arana ◽  
R. Antolín ◽  
E. Diez ◽  
G. Borge ◽  
...  

Author(s):  
Zuhaili Idham ◽  
Ahmad Syahmi Zaini ◽  
Nicky Rahmana Putra ◽  
Nurfarhain Mohamed Rusli ◽  
Noor Sabariah Mahat ◽  
...  

2021 ◽  
Vol 7 (2) ◽  
pp. 41
Author(s):  
Farzaneh Farivar ◽  
Pei Lay Yap ◽  
Ramesh Udayashankar Karunagaran ◽  
Dusan Losic

Thermogravimetric analysis (TGA) has been recognized as a simple and reliable analytical tool for characterization of industrially manufactured graphene powders. Thermal properties of graphene are dependent on many parameters such as particle size, number of layers, defects and presence of oxygen groups to improve the reliability of this method for quality control of graphene materials, therefore it is important to explore the influence of these parameters. This paper presents a comprehensive TGA study to determine the influence of different particle size of the three key materials including graphene, graphene oxide and graphite on their thermal parameters such as carbon decomposition range and its temperature of maximum mass change rate (Tmax). Results showed that Tmax values derived from the TGA-DTG carbon combustion peaks of these materials increasing from GO (558–616 °C), to graphene (659–713 °C) and followed by graphite (841–949 °C) The Tmax values derived from their respective DTG carbon combustion peaks increased as their particle size increased (28.6–120.2 µm for GO, 7.6–73.4 for graphene and 24.2–148.8 µm for graphite). The linear relationship between the Tmax values and the particle size of graphene and their key impurities (graphite and GO) confirmed in this study endows the use of TGA technique with more confidence to evaluate bulk graphene-related materials (GRMs) at low-cost, rapid, reliable and simple diagnostic tool for improved quality control of industrially manufactured GRMs including detection of “fake” graphene.


Sign in / Sign up

Export Citation Format

Share Document