Centrifugation Time Research Articles

Ultrasound assisted deep eutectic solvent based liquid phase microextraction for the preconcentration and spectrophotometric determination of amaranth (E123) in water and food samples

A novel and easy environmental deep eutectic solvent based liquid phase microextraction method has been developed for the separation-preconcentration and spectrophotometric determination of amaranth. The deep eutectic solvent system is composed of tetrabutyl ammonium bromide (TBABr) and decanoic acid (DA). 300 µL of emulsifying agent tetrahydrofuran (THF) and 600 µL of deep eutectic solvent (DES) were employed. Quantitative recoveries were obtained at pH 5.0, sonication and centrifugation times of two minutes, and a model solution volume of 20 mL. The amaranth concentration was measured in a micro-cuvette spectrophotometer at 520 nm. The limit of detection (LOD), limit of quantification (LOQ), and preconcentration factor (PF) were 23 µg/L, 76 µg/L, and 33.3, respectively. The presented microextraction method has been validated by analyzing food and water samples by the method of standard addition.

Difference in temporal and spatial distribution pattern of cyanobacteria between the sediment and water column in Lake Chaohu

The evaluation about the relative distribution of cyanobacterial biomass between the sediment and water column would be indispensable to understand if benthic cyanobacteria are important to cyanobacterial biomass in the water column. A separation method for the rapid quantification of benthic cyanobacteria in Lake Chaohu was developed by density-gradient centrifugation. A 24 full factorial design and response surface methodology was employed to optimize the extraction protocol. Under the optimal operating parameters including 29% Percoll solution, 30 min centrifugation time, 7200 r/min centrifugation speed, and a 1:10 ratio between the volume of sediment and Percoll solution, the recovery rate of cyanobacteria in sediment was 96.73%. Temporal and spatial variations in cyanobacterial biomass in water and sediment were investigated monthly throughout a whole year. In general, cyanobacterial biomass per square centimeter in the water column showed high spatial-temporal changes, tending to increase in February and reaching a peak in April at some sites due to the growth of Dolichospermum. The second peak arrived in July and September and was caused by the rapid growth of Microcystis. Concurrently, cyanobacteria biomass per unit area in sediment showed a clear temporal change pattern, increasing from October and reaching a peak level in February at all the sampling sites. The average ratio of cyanobacterial biomass in water to that in sediment was lowest in January at 1.48 and increased to the highest level in July at 318.61. Although Microcystis and Dolichospermum were dominant species in the water column, only Microcystis was observed in the Percoll solution extraction from sediment. Microscopic observation revealed that a very small fraction of Microcystis cells could survive in sediment, and most of the cells decomposed when the water temperature increased after June. Therefore, the contribution of the recruitment of cyanobacteria could be negligible in Lake Chaohu.

FINE-TUNING SPEED AND TIME OF CENTRIFUGATION FOR SPERM WASH PROCESS IN MALE FACTOR

The objective of this study is to determine whether speed and/or time of centrifugation for sperm wash process effects on the motility of harvested sperm and total motile sperm count. DESIGN: Among donated frozen sperm for quality control purpose, male factor sperm was used in this study. According to WHO 5th edition, sperm wash for diluted semen sample should be centrifuged at 300-500g for 5-10 minutes. Six experimental condition was set as Ex1: 500g for 10 min, Ex2: 400g for 10 min, Ex3: 300g for 10 min, Ex4: 500g for 5 min, Ex5: 400g for 5 min, Ex6: 300g for 5 min. Each experiments were repeatedly performed five times using same centrifuge (Eppendorf 5702). Donated frozen sperm were thawed for 20 min at 37°C. Equal volume of pre-warmed sperm wash was added into thawed sperm and six aliquots were prepared for experiment. Average sperm motility was 17% (range: 9% to 30%) and average progressive motility was 12% (range: 6% to 20%). We analyzed the difference of motility of harvested sperm after single centrifugation and Ex1 was used as control group. The ANOVA and t-test were used. A p value <0.05 was considered significant. After six different condition of centrifugation, manual sperm count for motility was performed by one andrologist to reduce personal bias. Comparing to Ex1, sperm motility in Ex3 and Ex6 was significantly higher than that of other groups (p=0.028 and p=0.013, respectively). Progressive motility in Ex3 and Ex6 was also significantly higher than other groups (p=0.012 and p=0.0003). There is no significant difference of sperm motility between Ex3 and Ex6. Between 300g and 500g for 5 min to 10 min range, 300g for 5 min was sufficient for sperm wash with keeping good sperm motility. After six different condition of centrifugation, manual sperm count for motility was performed by one andrologist to reduce personal bias. Comparing to Ex1, sperm motility in Ex3 and Ex6 was significantly higher than that of other groups (p=0.028 and p=0.013, respectively). Progressive motility in Ex3 and Ex6 was also significantly higher than other groups (p=0.012 and p=0.0003). There is no significant difference of sperm motility between Ex3 and Ex6. Between 300g and 500g for 5 min to 10 min range, 300g for 5 min was sufficient for sperm wash with keeping good sperm motility.

A dispersive liquid–liquid microextraction method based on solidification of floating organic droplet for determination of antiviral agents in environmental water using HPLC/UV

In this work, mixed solvents have been tried for liquid microextraction of four antivirals (sofosbuvir, daclatasvir, velpatasvir, and ledipasvir) with the aid of HPLC/UV as an analytical method. The results showed that liquid microextraction using mixed dodecanol/chloroform was better than using either chloroform or 1-dodecanol alone. The maximum enrichment was achieved using a mixture of dodecanol and chloroform (70:30, v/v). Other critical variables that could affect the extraction efficiency were optimized, including the extractant volume, pH of the diluent, dispersion technique, vortex, and centrifugation time. The optimum extraction was attained using 30 µL of the mixed solvent and the pH of aqueous sample was adjusted to 8. The mixture was vortexed for 1.5 min at 1000 RPM and centrifuged for 1 min at 4000 RPM. Using these optimum conditions, the method was linear over the range of 0.01–5.0 µg/mL with limits of detection of 0.006, 0.003, 0.003, and 0.012 µg/mL for sofosbuvir, daclatasvir, velpatasvir, and ledipasvir, respectively. The method was applied to river water analysis with acceptable % recoveries in the range of 98.18–101.96 %, while the values of %RSD were in the range of 0.69 – 1.87. This work shows the high potential of using mixed solvents as extractants in liquid phase microextraction, compared with conventional methods that employ a single extractant.

Visible near Infrared Spectroscopic Evidence of the Purification and Dispersion of Single-Walled Carbon Nanotubes

The application of dispersible single-walled carbon nanotubes in water is required in many fields, such as mechanics, thermology, electricity, etc. In this paper, single-walled carbon nanotube samples were dispersed in sodium deoxycholate aqueous solution with the assistance of ultrasonic crushing. The effects of centrifugal time, concentration and centrifugal velocity on dispersion were investigated. After centrifugal separation, the dispersible single-walled carbon nanotubes solution in water was obtained. The dispersion behavior of single-walled carbon nanotubes in sodium deoxycholate aqueous solution was further investigated by Uv-visible near infrared spectrum and electrochemical cyclic voltammetry curve. At the same time, characterization results of Uv-visible near infrared spectrum shew that the purity of single-walled carbon nanotubes was improved. The cyclic voltammetry curves of single-walled carbon nanotubes after purification and dispersion were tested by electrochemical method, and the electron transfer behavior of single-walled carbon nanotubes after purification and dispersion was investigated.

Sperm Quality and Deoxyribonucleic Acid Fragmentation after 5 and 10 min Centrifugation with Swim-Up Processing Technique: A Prospective Cohort Study

AIM: This study aimed to assess the difference in sperm concentration, total motility, progressive motility, and deoxyribonucleic acid (DNA) fragmentation index (DFI) before and after processing with 5 and 10 min swim-up (SU). METHODS: Fifty patients who met the study inclusion criteria from June 2020 to October 2020 were subjected to routine semen and sperm DNA fragmentation analysis. Each of the samples was then divided into three tubes, one as control and the others were processed using the SU method with 5 and 10 min centrifugation time, respectively. After being processed, the samples were subjected again to routine semen and sperm DNA fragmentation analysis. The results were being compared among three groups. RESULTS: The sperm concentration after 5 and 10 min SU (27.78–39.79 and 35.36–51.09, respectively; p &lt; 0.05) was significantly higher compared to fresh semen (24.85–32.33). The total motility before and after 5 and 10 min SU were 43.78–51.08, 97.66–98.20, and 97.86–98.20, respectively. The progressive motility after 5 and 10 min SU (0–41 and 0–54, respectively) was significantly higher than fresh semen (0–24; p &lt; 0.05). The DFI was significantly better after 5 min SU (3.82–6.98) compared to fresh semen and after 10 min SU (13.48–19.04 and 1–25, respectively; p &lt; 0.05). CONCLUSION: Prolonged centrifugation time may yield a higher number of sperm concentration and motility, but it may also lead to a higher DFI. Hence, a shorter centrifugation time should be used for a better semen quality intended for assisted reproductive technologies.

Determination of fluoroquinolones illegally added in traditional prostate medicines by ultrasonic-assisted dispersive liquid liquid micro-extraction based on deep eutectic solvent combined with quantitative 19F nuclear magnetic resonance method

We optimized the combination of deep eutectic solvent (DES)-based ultrasonic-assisted dispersive liquid-liquid microextraction method and 19F qNMR for quantitation of 5 kinds of fluoroquinolone antibiotics illegally added to drugs for prostatitis treatments (Ciprofloxacin, Levofloxacin, Sparfloxacin, Gatifloxacin, Enrofloxacin). In this study, methyltrioctylammonium bromide and n-capric acid were mixed at a 2:1 M ratio to prepare hydrophobic DES. The newly prepared DES was used as the extract. Fluoroquinolone antibiotics were extracted from saturated ammonium sulfate solution and detected by 19F qNMR. In this study, the effects of extraction conditions such as DES volume, salt dosage, ultrasonic time, centrifugal time, and vortex time on extraction efficiency were systematically investigated. Under the optimal conditions, good linearity (correlation coefficient r: 0.9993–0.9998) was obtained with a detection limit of 0.1 μg mL−1. The extraction reproducibility (RSD) of intra-day and inter-day were below 5.01 and 5.98%, respectively. This study showed feasibility of detection of fluoroquinolone antibiotics illegally added in traditional medicines for prostatitis treatments by DES-based ultrasonic-assisted dispersion-liquid microextraction combined with 19F qNMR method.

COMPARISON OF DIFFERENT METHODS OF CENTRIFUGATION FOR OPTIMUM PREPARATION OF PLATELET RICH PLASMA (PRP)&amp; FRAMING A CUSTOMIZED PRP PROTOCOL-AN INNOVATIVE APPROACH

Introduction:The rationale behind the therapeutic potential of the high concentration of platelets in PRP (Platelet Rich Plasma) for intervention procedures of soft tissue injuries is often challenged by the ability of the centrifugation methods followed in extracting the high quality PRP with prompt contented quantity too.This study aims to unravel the basic science of PRP preparation involved in centrifugation protocols, spin methods, speed and time duration of centrifugation to obtain consistent therapeutic platelets yield. Materials and Methods:30 participants were subjected to intervention procedures using PRP. For therapeutic purpose 3 centrifugation protocol types are followed. Ø Protocol 1-Conventional Old protocol Ø Protocol 2-Customised New protocol Ø Protocol 3-Spin Reversal of the routine -hard spin followed by soft spin The Platelets and WBC concentration and composition in the final autologous PRP sample harvested as a result of double centrifugation method are compared for quantity and efficiency. Results:The maximum PCF-3.21 times above baseline and PRR -64.21% are through new customized spin proving its efficiency. As determined by one-way ANOVA, there is statistically significant difference between the PROTOCOL groups (1,2,3) for the variables PRP platelet count, PRP Leucocytes, PCF, PRR. A Tukey post hoc test revealed that there is statistically significant value for Protocol 2 and Protocol 3 compared to the Protocol 1 for PRP platelet count, PCF and PRR whereas for PRP Leucocytes, there was a statistically significant difference between the Protocol 2 and Protocol 3 which again implicates the necessity of spin reversal in yielding better quantity of leucocytes. Conclusion:To produce PRP samples with consistent and reproducible compositionsof platelets and leucocytes with better quality control standard through a detailed, precise and stepwise description of the manufacturing protocol has been explained in our study. Our perspective is in standardizing a safe, simple protocol that can be followed to obtain an optimal consistent platelet yield without the use of commercial kits, which has been proved statistically too.

Enhanced Optical and Thermal Performance of QD White LEDs Using a Centrifugation Packaging Structure

In this study, we propose a centrifugation packaging (CP) structure to enhance the optical and thermal dissipation performance of LEDs, using SBA-15 particles to facilitate the sedimentation and dispersion of QDs. The results indicate that the EL spectra of the LEDs remains almost unchanged after the centrifugation time of 60 min and a CP structure can be obtained. The radiation power and luminous flux of LEDs with a CP structure improve by 9.1% and 10.4%, respectively, compared with the uniform distribution (UD) structure. The surface temperature of LED devices with the CP structure is reduced to 34.4 °C from 41.8 °C at a current of 100 mA. Furthermore, the simulation results show that the maximum temperature in the CP structure is 22.4% lower than that in the UD structure at a current of 500 mA. Thus, this study can provide a new perspective for designing settlement structures of QD-LEDs to enhance their optical and thermal performance.

Scale-up of green synthesis and characterization of silver nanoparticles using ethanol extract of Plantago major L. leaf and its antibacterial potential

Green synthesis of silver nanoparticles (Ag NPs) utilizing plant extracts has been widely optimized these days because of its eco-friendly, simple, and cost-effective manner. This present study was performed to evaluate the scale-up trial on synthesis parameter and centrifugation duration of Plantago major L. leaf ethanolic extract in the green synthesis of Ag NPs. Leaf extract concentration of 0.25%, 70 °C of temperature, 60 min of synthesis time, and 30 min of centrifugation time were concluded as the optimized scale-up condition of green synthesis. The scale-up trial resulted in spherical silver nanoparticles with an average size 12.2±5.11 nm, proven from various spectroscopic (UV–Vis, EDS, FTIR), microscopic observations (SEM, FE-TEM), and other observations (SAED, DLS, XRD). The synthesized Ag NPs also exhibit promising antibacterial activity against several tested bacteria at 20 μg mL−1 of dosage. This study offers nine times higher yield of the synthesized Ag NPs (107.2±6.82 mg) at about the same making time of smaller scale of green synthesis. Sufficient nanoparticles will provide flexibility to carry out its characterization in an efficient manner and further bioactivity test and/or formulation experiments, such as in cosmetics, medical ointments, and other pharmaceutical products.

In-syringe ionic liquid-dispersive liquid-liquid microextraction coupled with HPLC for the determination of trans,trans-muconic acid in human urine sample.

trans,trans-Muconic acid has been widely used as a biomarker in biological monitoring of benzene-exposed workers during routine occupational health services. In the present study, a novel microextraction technique, in-syringe ionic liquid-dispersive liquid-liquid microextraction, was implemented for preconcentration of trans,trans-muconic acid followed by analytical determination by high-performance liquid chromatography with ultraviolet detection. Moreover, the important variables affecting the performance of applied microextraction technique including needle diameter, volume of the spiked sample, volume of the ionic liquid, salt addition, rotation speed of centrifugation, centrifuge time, and ultrasonic time were optimized by experimental design. A good linear relationship was observed at the range of 0.032-10μg/mL between the peak area and the concentration levels (R2 =0.9997). The limit of detection and extraction recovery for trans,trans-muconic acid were 0.011μg/mL and>96.2%, respectively. This method provided easy and rapid analysis of low amounts of trans,trans-muconic acid in human urine with simple equipment.

Synthesis and characterisation of MCM-41@SiO2-NH-pydc as a new nano mesoporous sorbent: application for the simultaneous preconcentration of cationic dyes previous spectrophotometric determination, using taguchi experimental design

ABSTRACT In this study, a new nano mesoporous MCM-41@SiO2-NH-pydc was successfully synthesised and was used as a new and low-cost adsorbent for the simultaneous influential clean-up, preconcentration and determination of crystal violet (CV) and auramine O (AO) dyes. The as-synthesised sorbent was characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDX), thermogravimetric (TGA) and derivative thermogravimetric (DTG) and Brunauer–Emmett–Teller (BET) techniques. The extraction performance was evaluated by dispersive solid phase micro extraction (DSPME) of CV and AO from real samples. The analysis was carried out by UV-Vis spectrophotometric. The analytical results confirmed that theMCM-41@SiO2-NH-pyd could be an appropriate candidate as asorbent forDSPME. The maximum recoveries (95.95% and 92.95% for CV and AO, respectively) was obtained at 0.015 g MCM-41@SiO2-NH-pydc sorbent, pH = 8.0, 500 μL DMF as eluent solvent, 20 and 10 min extraction and centrifuge time, respectively, and 50 second desorption time. After the optimum conditions, the limit of detection (LOD), quantification (LOQ) and linear range were obtained, 0.0010, 0.0033 and 0.008–0.6 mg L−1 for CV and 0.0056, 0.0187 and 0.03–1.5 mg L−1for AO, respectively. The relative standard deviations (RSD) for five analyses were 4.2% for CV and 4.6% for AO. In comprising with the previous reported methods, the developed method provided a relatively in expensive, time-saving and environmentally friendly advantages. The developed analytical method can be applied for the determination of CV and AO with sufficient sensitivity as well as acceptable reproducibility.

Physical decoloration in the concentration process of natural rubber

AbstractNatural rubber (NR) latex contains many components, especially non‐rubber components, which can affect the color of products made from it. There is a growing demand in NR products which are lightly colored or color filled. One way to reduce the yellow color of NR is to remove non‐rubber components, for example, lipids and proteins, from NR. This study focused on several NR latex decoloration techniques, including controlling centrifugation speed and time as well as percentage of total solid content (% TSC) of field latex. It was found that the best condition to reduce yellow color was centrifugation of the field latex containing less than 35% TSC at 12,000 rpm for 30 min. In addition, decoloration of NR latex was very effective by washing the centrifuged latex at least twice. Other factors, such as storage time and drying conditions, promoted coloration of NR due to the oxidation of the non‐rubbers.

Study of Cucurbit[7]uril nanocoating on epitaxial graphene to design a versatile sensing platform

Present study aimed to develop nanocoating of cucurbit[7]uril (CB[7]) on surfaces of silicon and epitaxial graphene using drop casting and spin coating techniques. Here, we report a systematic study for the influence of sonication, probe sonication, and centrifugation time on the dispersion of CB[7] in aqueous solutions for the preparation of high-quality CB[7] nanocoating. Spin speed, spin time, and spin acceleration have been optimised to attain uniform films with minimum rms. Atomic force microscopy is used to study morphology, rms, and height of CB[7] nanocoating under different parameters. The presence of CB[7] on the nanocoating and its binding nature was determined by Infrared absorption and X-ray photoelectron spectroscopy. The present method of CB[7] nanocoating preparation is easy, versatile, scalable, and does not need the addition of electrolyte additives. Prepared CB[7] films are high-quality, uniform, and could be used as a novel sensing platform to tether required functional groups.

Influencing factors for preparation of platelet-rich plasma in horses

There is no consensus in the literature as to the best platelet-rich plasma (PRP) acquisition method or the ideal platelet concentration to stimulate tissue repair. Besides that, most studies do not provide a clear and replicable description of the methods used, which makes standardization and result comparison difficult. Thus, this study aimed to accurately describe the method and evaluate factors influencing PRP preparation in equines. In this regard, two protocols were used, P1 and P2, based on two centrifugation methods, which differed in blood volume, speed and time, and platelet pipetting and resuspension. In conclusion, factors such as centrifugation strength and time are essential to obtain PRP with adequate platelet count. However, other factors such as tube type and plasma pipetting and resuspension methods directly interfere with the replicability of the technique, and hence influencing PRP applicability.

Medicines with active pharmaceutical ingredient diosmin: plaining of sample preparation

BACKGROUND: Most drugs in the form of tablets contain diosmin in the micronized flavonoid fraction. This is the reason for the low level recovery by means of solid-liquid extraction.&#x0D; AIM: to determine optimal conditions for sample preparation of some drugs with active pharmaceutical ingredient diosmin with the use of mathematical experiment planning (Box-Behnken design).&#x0D; MATERIALS AND METHODS: The study subjects were tablets Detralex 1000 mg, Venarus 900 mg, Detravenol 1000 mg, Flebaven 1000 mg, Phlebopha 600 mg, Phlebodia 600 mg. Estimation of diosmin recovery by the method of solid-liquid extraction was made according to the algorithm of full factorial design with three level factors (Box-Behnken design).&#x0D; RESULTS: The effect of some factors determining the extraction of diosmin from tablets Detralex 1000 mg, Venarus 900 mg, Detravenol 1000 mg, Flebaven 1000 mg, Phlebopha 600 mg, Phlebodia 600 mg was estimated. Mathematical (regression) models of solid-liquid extraction of diosmin for each drug were developed. The most significant factor determining the diosmin recovery from drugs (tablet formulation) is the sodium hydroxide concentration. Other factors (acetonitrile concentration, extraction time, centrifugation time, addition of ammonium sulfate) fail to exert significant effect. The optimal value of sodium hydroxide concentration is 0.02 mol/l. Diosmin recovery doesnt increase after the increase of the sodium hydroxide concentration above 0.02 mol/l.

An easy and green amine-based microextraction strategy combined UV–Vis spectrophotometric detection for mercury in natural water samples

An amine-based microextraction method was established for preconcentration of mercury by forming a 1-(2-pyridylazo)-2-naphthol (PAN) chelate complex. The Hg (II)-PAN hydrophobic complex was extracted into the N,N-dimethyl-n-octylamine phase at pH 9.5, after the pre-concentration of Hg (II), the absorption spectrum was taken with UV–Vis spectrophotometer at 555.0 nm. The effects of important analytical parameters such as pH, PAN amount, N,N-dimethyl-n-octylamine volume, sample volume and matrix effects for quantitative recovery were investigated and optimized. 0.05% (w/v) PAN volume, N,N-dimethyl-n-octylamine volume, vortex time and centrifugation time were optimized as 0.4 mL, 0.1 mL, 1 min and 15 min, respectively. The validity of the developed liquid phase micro-extraction method was checked by standard addition-recovery experiments. The presented microextraction method was successfully applied for mercury determination in natural water samples. The mercury concentration in natural water samples ranged from 0.20 to 1.42 µg mL-1. The limit of detection (LOD), limit of quantification (LOQ) and preconcentration factor (PF) were found as 0.035 μg L−1, 0.12 μg L−1 and 26.67, respectively.

Evaluation of the Barricor Tube in 28 Routine Chemical Tests and Its Impact on Turnaround Time in an Outpatient Clinic.

BackgroundWe recently introduced the Barricor (BD, Franklin Lakes, NJ, USA) plasma separation tube, which uses a mechanical separator instead of a gel. We evaluated the effects of using the Barricor tube in a stat (statin) laboratory on the results and turnaround time (TAT) of routine chemical tests. We verified the impact of Barricor tube on reducing TAT and providing results similar to those obtained using serum separator tubes (SSTs).MethodsWe collected venous blood samples from 166 outpatients in Barricor tubes and SSTs and measured 28 routine analytes using an AU5800 instrument (Beckman Coulter, Brea, CA, USA). TAT indexes were compared before and after using Barricor tube.ResultsMean percent differences were <5%, except for alanine aminotransferase , total CO2, high-density lipoprotein, phosphate, total protein, and direct bilirubin. The median TAT decreased from 45 to 38 minutes, and the rate of a TAT >60 minutes decreased from 7.84% to 2.66%, which was approximately one-third of that for SST. The reduction in TAT was attributable to a decrease in centrifugation time. Incomplete clotting and repeated centrifugation, which occurred frequently when using SST, also decreased after using the Barricor tubes.ConclusionsThe Barricor tube is an alternative to SST for routine chemical tests in institutions aiming to reduce TAT, with clinically allowable differences in test results.

The Lucerne Protocol for the Production of Autologous Serum Eyedrops.

There are a variety of protocols for manufacturing autologous serum (AS) eye drops. The Lucerne protocol for the production of AS eye drops uses a slightly reduced gravitational (g)-force and time for the centrifugation process (2500 × g for 10 minutes), compared to previously published optimised protocols, to obtain high levels of epitheliotropic growth factors (3000 × g for 15 minutes). The goal of this study was to compare the concentrations of growth factors, albumin and lysozyme in autologous serum eye drops manufactured with these protocols. Blood from 5 healthy volunteers was placed in plastic tubes without an anticoagulant. Tubes from each donor were left in a vertical position for 2 hours at room temperature to facilitate coagulation, followed by centrifugation at either 2500 × g for 10 minutes or at 3000 × g for 15minutes at room temperature. The serum levels of beta nerve growth factor (β-NGF), transforming growth factor β1 (TGF-β1), epidermal growth factor (EGF), hepatocyte growth factor (HGF), platelet-derived growth factor BB (PDGF-BB) and vascular endothelial growth factor A (VEGF-A) were measured in triplicate with a multi-analyte Simple Plex platform. The Simple Plex cartridge allows each sample to be run in triplicate for each analyte and prevents any interaction between the antibody components for each biomarker. The serum level of albumin was measured by turbidimetric immunoassay Tina-quant and of lysozyme by single radial immunodiffusion assay. For all analytes, the reduced g-force and centrifugation time did not result in a significant difference in serum levels. The Lucerne protocol for the production of autologous serum eye drops with reduced g-force and a shorter centrifugation time does not affect the concentrations of the main epitheliotropic growth factors, albumin and lysozyme, in AS eye drops.

Preparation of Silymarin–quercetin Loaded Nanoparticles by Spontaneous Emulsification Solvent Diffusion Method Using D-alpha-tocopheryl Poly (Ethylene Glycol) 1000 Succinate

Silymarin, a flavonolignan, derived from Silybum marianum, family Asteraceae has long been used as a hepatoprotective remedy. Silymarin has cytoprotective activities due to its antioxidant property and free radical scavenging activity. The pharmacokinetic studies of past three decades revealed that silymarin has poor absorption, rapid metabolism especially by Phase II metabolism and ultimately poor oral bioavailability. Quercetin, a flavonoid present in edible vegetables and fruits, It is a potent antioxidant and shows a wide range of biological functions. Quercetin improves blood levels and efficacy of number of drugs since it is P-Glycoprotein inhibitor and also inhibits drug metabolizing enzymes. Both silymarin and quercetin were, poorly soluble in the water shows low bioavailability. The advanced type of formulation like polymeric nanoparticles (PNPs) can be successfully utilised for bioavailability enhancement and targeting the Silymarin-quercetin to hepatocytes. A controlled release PNPs of silymarin-quercetin were prepared by spontaneous emulsification solvent diffusion (SESD) method using Poly Lactic-co-Glycolic Acid (PLGA) as biodegradable polymer, D-alpha-tocopheryl poly (ethylene glycol) 1000 succinate (TPGS) used as a solubilizer, as an emulsifier. TPGS as an emulsifier and further as a matrix material blended with PLGA was used to enhance the encapsulation efficiency and improve the drug release profile of nanoparticles. Different formulations with various drug: polymer ratios and volume and concentration of surfactant, centrifugation time were evaluated. The effect of formulation parameters such as drug/polymer ratio, volume and surfactant content were evaluated. The surface morphology and size of the nanoparticles were studied by scanning electron microscopy (SEM) Transmission electron microscopy (TEM). Drug encapsulation efficiency and in vitro drug release profiles of nanoparticles were determined using UV spectrophotometry. The nanoparticles prepared with combination of both the drugs in this study were spherical with size range of 100–200 nm. It was shown that TPGS was a good emulsifier for producing nanoparticles of hydrophobic drugs and improving the encapsulation efficiency and drug loading and drug release profile of nanoparticles. Although the amount of the TPGS used had a significant effect on the nanoparticle size and morphology, the drug loading and release profile of nanoparticles