Effect of pH variation on cross-linking of water-soluble and acid-soluble chitosan with sodium tripolyphosphate and gallium-67

2021 ◽  
Vol 15 ◽  
Author(s):  
Narjes Damavandi Kamali ◽  
Alireza Alishahi ◽  
Marzieh Heidarieh ◽  
Saeed Rajabifar ◽  
Hojat Mirsadeghi ◽  
...  
Keyword(s):  
Incubation Time ◽  
Room Temperature ◽  
Sodium Tripolyphosphate ◽  
Radiochemical Yield ◽  
Water Soluble ◽  
Ph Variation ◽  
Food And Feed ◽  
Water Treatments ◽  
Layer Chromatography ◽  
Gallium 67

Background: Chitosan is a cationic biopolymer obtained from deacetylating chitin, a naturally compoundpresent in crustacean shell, fungi and exoskeleton of insects. Chitosan has various applications including drug and gene delivery systems, wound dressing and as scaffolds for tissue engineering, agriculture, textile, food and feed nanotechnology, waste water treatments. chitosan-TPP particle figure out as the most important and stable nanoparticle for chitosan application in various fields. Objective: At this study chitosan was chemically modified by sodium tripolyphosphate (TPP). Afterward, TPP-chitosan was radiolabeled with gallium-67 radionuclide. The effect of several factors on labeling yield such as chitosan solubility, acidity and concentration of TPP-chitosansolution, incubation time with gallium-67 were investigated. Methods: To prepare [67Ga] gallium-chitosan complex, chitosan (0.5 ml) was dissolved in 2.2 mCi of [67Ga] gallium chloride solution. The obtained solution was stirred for 5 min and then was kept for 30 min at room temperature. Radiochemical purity and radiolabeling yield was measured via radiochromatography that it was performed by using a radio thin-layer chromatography (TLC) scanner instrument. To investigate the effect of chitosan kind and concentration on the labeling yield, two kinds of chitosan (acid-soluble chitosan and water-soluble chitosan) with two different concentrations (1% and 0.5%) at different pH were used. In addition, labeling efficiency and stability of the 67Ga-TPP-chitosan complex (acidic/water soluble chitosan) at both concentrations (0.5 and 1%) at room temperature was assessed for 30, 45 and 60 min. Results: The incubation time has not significant effect on labeling yield. The acidic soluble chitosan, which has highest radiolabeling yield at pH=9.3-10.4, water soluble chitosan showed the highest radiolabeling yields at pH > 5. Also, the prepared complex was stable in the final solution at room temperature and can even be used 24 hours after preparation for further application. Conclusion: Taken together, the TPP modified water soluble chitosan at concentration 0.5 % depicted the highest radiochemical yield (>95 %) at the optimized condition (pH= 6.2–7.6). Therefore, TPP modified water soluble chitosan can be an effective carrier for therapeutic radionuclides for tumor treatment.

Tyrosine-Selective Bioconjugation with Iminoxyl Radicals

2020 ◽  
Author(s):  
Katsuya Maruyama ◽  
Takashi Ishiyama ◽  
Yohei Seki ◽  
Kounosuke Oisaki ◽  
Motomu Kanai
Keyword(s):  
Reaction Time ◽  
Steric Hindrance ◽  
Room Temperature ◽  
Water Soluble ◽  
Light Irradiation ◽  
Sodium Ascorbate ◽  
Iminoxyl Radical ◽  
Short Reaction Time ◽  
Modified Peptides ◽  
The Stability

A novel Tyr-selective protein bioconjugation using the water-soluble persistent iminoxyl radical is described. The conjugation proceeded with high Tyr-selectivity and short reaction time under biocompatible conditions (room temperature in buffered media under air). The stability of the conjugates was tunable depending on the steric hindrance of iminoxyl. The presence of sodium ascorbate and/or light irradiation promoted traceless deconjugation, restoring the native Tyr structure. The method is applied to the synthesis of a protein-dye conjugate and further derivatization to azobenzene-modified peptides.

Water-Soluble Imine Ligand/Palladium-Catalyzed Suzuki Reaction at Room Temperature

2010 ◽  
Vol 31 (10) ◽  
pp. 1277-1280
Author(s):  
Chun LIU ◽  
Qijian NI ◽  
Pingping HU ◽  
Hao YUAN ◽  
Zilin JIN
Keyword(s):  
Room Temperature ◽  
Suzuki Reaction ◽  
Water Soluble ◽  
Palladium Catalyzed

Dynamics of Anthracene Excimer Formation within a Water-Soluble Nanocavity at Room Temperature

2021 ◽  
Vol 143 (4) ◽  
pp. 2025-2036
Author(s):  
Aritra Das ◽  
Ashwini Danao ◽  
Shubhojit Banerjee ◽  
A. Mohan Raj ◽  
Gaurav Sharma ◽  
...  
Keyword(s):  
Room Temperature ◽  
Water Soluble ◽  
Excimer Formation

scholarly journals A Novel Photosynthesis of Carboxymethyl Starch-Stabilized Silver Nanoparticles

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
M. A. El-Sheikh
Keyword(s):  
Silver Nanoparticles ◽  
Room Temperature ◽  
Colloidal Solution ◽  
Synthesis Method ◽  
Silver Ions ◽  
Water Soluble ◽  
Synthesis Process ◽  
Carboxymethyl Starch ◽  
Round Shape ◽  
First Time

The water soluble photoinitiator (PI) 4-(trimethyl ammonium methyl) benzophenone chloride is used for the first time in the synthesis of silver nanoparticles (AgNPs). A new green synthesis method involves using PI/UV system, carboxymethyl starch (CMS), silver nitrate, and water. A mechanism of the reduction of silver ions to AgNPs by PI/UV system as well as by the newly born aldehydic groups was proposed. The synthesis process was assessed by UV-vis spectra and TEM of AgNPs colloidal solution. The highest absorbance was obtained using CMS, PI and AgNO3concentrations of 10 g/L, 1 g/L, and 1 g/L, respectively; 40°C; 60 min; pH 7; and a material : liquor ratio 1 : 20. AgNPs so-obtained were stable in aqueous solution over a period of three weeks at room temperature (~25°C) and have round shape morphology. The sizes of synthesized AgNPs were in the range of 1–21 nm and the highest counts % of these particles were for particles of 6–10 and 1–3 nm, respectively.

One-Pot Synthesis of Water Soluble, Extremely Small-Sized Superparamagnetic Magnetite Nanoparticles

2012 ◽  
Vol 531 ◽  
pp. 219-222
Author(s):  
Li Hua Shen ◽  
Ting Shang ◽  
Jun Zhou ◽  
Dong Wang ◽  
Yu Han ◽  
...  
Keyword(s):  
Magnetite Nanoparticles ◽  
Room Temperature ◽  
Colloidal Stability ◽  
Aqueous Media ◽  
Mri Contrast Agents ◽  
Water Soluble ◽  
Potential Candidate ◽  
One Pot ◽  
Mri Contrast

Extremely small-sized superparamagnetic magnetite nanoparticles of 3Cit). The resulting Cit-coated magnetite nanoparticles exhibited long-term colloidal stability in aqueous media without any surface modification. Regarding the magnetic properties, the nanoparticles were superparamagnetic at room temperature, and might be the potential candidate for MRI contrast agents.

P–130 The effect of time of ejaculation and time of processing of semen on fertilization and ongoing pregnancy in IVF/ICSI treatments

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
A Badal ◽  
G Pilgram ◽  
D Diaz de Pool ◽  
L Van der Westerlaken
Keyword(s):  
Incubation Time ◽  
Room Temperature ◽  
Semen Quality ◽  
Sperm Quality ◽  
Gradient Centrifugation ◽  
Handling Time ◽  
Fertility Treatment ◽  
Ongoing Pregnancy ◽  
Ongoing Pregnancy Rate ◽  
Oocyte Vitrification

Abstract Study question Does time between ejaculation and processing, and time between processing and insemination/injection affect fertilization rate (FR) and ongoing pregnancy rate (OPR) in IVF/ICSI treatments? Summary answer Increasing time between processing and insemination significantly decreased the OPR after IVF. FRs after IVF/ICSI and OPR after ICSI were not affected by different time-intervals. What is known already The choice for IVF or ICSI depends on semen quality, however, this doesn’t affect the outcome of IVF/ICSI treatments (Mariappen et al 2018). After ejaculation, the percentage of motile spermatozoa decreases progressively at a rate of about 10%/hour (Makler 1979). According to the ESHRE-guideline, semen should be processed within 1 hour after ejaculation. In our laboratory, a validation was performed that confirmed a decrease in sperm motility after ejaculation. During incubation at 37 °C after processing, the sample remained stable in incubation medium (unpublished data). Therefore, we analyzed the effect of handling time and incubation time with regard to IVF/ICSI outcomes. Study design, size, duration This retrospective data analysis examines the effect of time between ejaculation and processing using density-gradient centrifugation (handling time) and time between processing and insemination (IVF)/injection (ICSI) (incubation time) on the FR and OPR, irrespective of the initial semen quality. A total of 1488 oocyte pickups (844 IVF, 644 ICSI) were included from 1060 patients undergoing fertility treatment between 2017 and 2019. Oocyte pickups without oocytes, with oocyte vitrification, or with donor oocytes were excluded. Participants/materials, setting, methods Anonymized data were obtained from the laboratory database ProMISe. Handling time and incubation time of the semen incubated at 37 °C and 5% CO2 were analyzed in relation to the occurrence of TFF (Total Fertilization Failure), FR and OPR. Linear and logistic regression was performed in SPSS version 25. In case of significant association, the data were adjusted for potential confounders, such as woman’s age, semen quality before and after preparation, and number of oocytes. Main results and the role of chance This study shows that increasing the incubation time of the semen significantly reduced the OPR per ET in IVF treatments (from 30,8% within 3,5 hours to 24,1% after 6 hours) even after adjusting for the potential confouders. However, the OPR in ICSI treatments was not significantly affected by the incubation time (rather, there was an opposite trend). Also, the handling time of the semen did not significant effect the FR per OPU and the OPR per ET in IVF/ICSI treatments. The overall percentage of TFF was 3,5% and did not differ significantly between the IVF and ICSI treatments. Both handling time and incubation time did not have a significant effect on the occurrence of TFF. An explanation for the decrease in OPR in IVF treatments may be that increasing the incubation time at 37 °C reduces the sperm quality as the capacitation reaction takes place too early, energy levels are reduced, DNA damage increases, or vacuoles arise in the sperm heads (Thijssen et al 2014, Jackson et al 2010, Peer et al 2007). Incubation at room temperature and reduction of the insemination time may improve OPR. Limitations, reasons for caution Retrospective study limitations (bias), no data on DNA fragmentation, incubation of semen only at 37 °C after preparation. Wider implications of the findings: Although it is recommended to produce semen at the IVF-department, our results show that an exception can be made, when production of a semen sample in a clinical setting is stressful, with no negative effect on the outcome. Furthermore, incubation-time at room temperature may have a positive effect on OPR. Trial registration number Not applicable

A modified bioassay for heat-stable Escherichia coli enterotoxin

1977 ◽  
Vol 23 (3) ◽  
pp. 331-336 ◽  
Author(s):  
S. Stavric ◽  
D. Jeffrey
Keyword(s):  
Escherichia Coli ◽  
Body Weight ◽  
Incubation Time ◽  
Evans Blue ◽  
Room Temperature ◽  
Blue Dye ◽  
Evans Blue Dye ◽  
Heat Stable ◽  
Stomach Distention ◽  
Time Required

Infant mice were injected orally with preparations containing Escherichia coli heat-stable enterotoxin (ST) and Evans blue dye, and incubated at 22 °C. With enterotoxin-positive samples, the stomach was distended and contained essentially all of the dye. With enterotoxin-negative samples, the stomach remained normal in size and the dye passed freely into the intestines. The time required to obtain the maximum ratio of gut weight to body weight varied from 30 to 90 min and was dependent upon the concentration of enterotoxin. Heat-labile enterotoxin (LT) had no effect during this period.Based on these findings, the mouse incubation time was reduced from 4 h to 90 min, and the heating of test samples was retained only for confirmation of ST. The location of the dye and stomach distention served as an indicator of positive responses to ST. Incubation of the mice at room temperature (22 °C) was found satisfactory.

scholarly journals 145 Effects of titrated levels of water soluble zinc amino acid complex on growth performance of nursery pigs

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 82-83
Author(s):  
Pornpim Aparachita ◽  
Scott Carter ◽  
Afton Sawyer ◽  
Jared Harshman ◽  
Zach Rambo ◽  
...  
Keyword(s):  
Amino Acid ◽  
Growth Performance ◽  
Block Design ◽  
Water Soluble ◽  
Acid Complex ◽  
Zinc Intake ◽  
Nursery Pigs ◽  
Amino Acid Complex ◽  
Water Treatments ◽  
Soluble Zinc

Abstract Previously, we reported that supplementing a water soluble zinc via drinking water (0 to 80 mg/L) to nursery pigs improved ADG and G:F. To evaluate the efficacy of higher titrated levels of this water soluble zinc amino acid complex (ProPath®Zn LQ, Zinpro Corporation, Eden Prairie, MN) on growth performance, 280 crossbred pigs (5.5 kg BW; 19 d of age) were randomly allotted to four water treatments (7 pens/treatment; 10 pigs/pen). The water treatments were 0, 40, 80 and 160 mg Zn/L of water. Pigs were fed in 4 dietary phases with complex, nutrient-dense, corn-soybean meal-based diets: Phase 1 and 2 (2,500 and 1,750 mg Zn as ZnO/kg; d 1–7 and 7–14, respectively) and Phase 3 and 4 (200 mg Cu as CuSO4/kg; d 14–23 and 23–42, respectively). Pigs and feeders were weighed weekly to determine ADG, ADFI, and G:F. Water meters were used to record and calculate water disappearance and zinc intake. Data were analyzed as a randomized complete block design. Orthogonal polynomial contrasts were used to determine linear and curvilinear effects. Water and total zinc intake increased linearly (P < 0.001) with increasing water zinc concentration. From d 0–14 when high dietary zinc was fed, there were no differences (P > 0.10) in ADG, ADFI, or G:F. However, from d 14–42 when basal levels of zinc were fed, quadratic improvements in ADG (0.545, 0.561, 0.578, 0.546 kg; P < 0.05) and G:F (0.686, 0.706, 0.723, 0.702; P < 0.01) were observed with increasing zinc via water. Similarly for d 0–42, ADG (0.435, 0.440, 0.454; 0.434 kg; P = 0.07), G:F (0.726, 0.740, 0.763, 0.749; P = 0.05) and average ending wt (23.73, 23.97, 24.55, 23.70 kg; P = 0.07) improved quadratically with increasing zinc. In conclusion, supplementing ProPath®Zn LQ via water resulted in improvements in ADG and G:F for nursery pigs.

Sign in / Sign up

Export Citation Format

Share Document