Understanding the role of water in the aggregation of poly(N,N-dimethylaminoethyl methacrylate) in aqueous solution using temperature-dependent near-infrared spectroscopy

2019 ◽  
Vol 21 (10) ◽  
pp. 5780-5789 ◽  
Author(s):  
Li Wang ◽  
Xuewei Zhu ◽  
Wensheng Cai ◽  
Xueguang Shao
Keyword(s):  
Phase Transition ◽  
Aqueous Solution ◽  
Infrared Spectroscopy ◽  
Hydrogen Bonds ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Temperature Dependent ◽  
Dimethylaminoethyl Methacrylate

Water with two hydrogen bonds plays an important role in the phase transition of LCST polymers.

Understanding the function of water during the gelation of globular proteins by temperature-dependent near infrared spectroscopy

2018 ◽  
Vol 20 (30) ◽  
pp. 20132-20140 ◽  
Author(s):  
Li Ma ◽  
Xiaoyu Cui ◽  
Wensheng Cai ◽  
Xueguang Shao
Keyword(s):  
Infrared Spectroscopy ◽  
Hydrogen Bonds ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Globular Proteins ◽  
Temperature Dependent

Water with two hydrogen bonds plays an important role in the gelation of globular proteins.

Understanding the role of water in the aggregation of proteins and polymers in aqueous solution using near-infrared spectroscopy

NIR news ◽  
2020 ◽  
Vol 31 (5-6) ◽  
pp. 21-24
Author(s):  
Yan Sun ◽  
Li Ma ◽  
Li Wang ◽  
Xuewei Zhu ◽  
Wensheng Cai ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Polymer Chains ◽  
Solution Temperature ◽  
High Concentration ◽  
Dimethylaminoethyl Methacrylate ◽  
Direct Formation ◽  
Different Temperatures

Water plays an important role in chemical and biological processes. For understanding the role of water in the aggregation of proteins and polymers, the variation of water structures in the process of aggregation was studied by near-infrared spectroscopy. The near-infrared spectra of the aqueous R2/wt and poly( N, N-dimethylaminoethyl methacrylate) solutions of different concentrations were measured at different temperatures. The spectral changes of the solutes and water with temperature were analyzed with the help of chemometric methods. In the aggregation of R2/wt, the water species with one hydrogen bond around the NH groups dissociate to initiate the change of the hydrogen bonding network of the hydration water, and then, the water molecules with two hydrogen bonds (S2) near the hydrophobic side chains release from the R2/wt, resulting in the formation of the ordered amyloid fibers. In the aggregation process of low concentration poly( N, N-dimethylaminoethyl methacrylate) solutions, the chains of the polymer tend to form a loose hydrophobic structure below 36°C and then aggregate into a micelle at a lower critical solution temperature of around 39°C. S2 acts as a bridge to connect the polymer chains in the loose hydrophobic structure, and the dissociation of the S2 bridge at high temperature is the reason for the formation of the micelle. For high concentration solution, however, the spectral information of S2 was not found in the aggregation, suggesting a direct formation of the micelle from the dehydrated chains.

scholarly journals New Directions in Exercise Prescription: Is There a Role for Brain-Derived Parameters Obtained by Functional Near-Infrared Spectroscopy?

2020 ◽  
Vol 10 (6) ◽  
pp. 342 ◽  
Author(s):  
Fabian Herold ◽  
Thomas Gronwald ◽  
Felix Scholkmann ◽  
Hamoon Zohdi ◽  
Dominik Wyser ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Physical Exercise ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Exercise Prescription ◽  
Brain Activity ◽  
Brain Health ◽  
Functional Near Infrared Spectroscopy ◽  
Internal Load

In the literature, it is well established that regular physical exercise is a powerful strategy to promote brain health and to improve cognitive performance. However, exact knowledge about which exercise prescription would be optimal in the setting of exercise–cognition science is lacking. While there is a strong theoretical rationale for using indicators of internal load (e.g., heart rate) in exercise prescription, the most suitable parameters have yet to be determined. In this perspective article, we discuss the role of brain-derived parameters (e.g., brain activity) as valuable indicators of internal load which can be beneficial for individualizing the exercise prescription in exercise–cognition research. Therefore, we focus on the application of functional near-infrared spectroscopy (fNIRS), since this neuroimaging modality provides specific advantages, making it well suited for monitoring cortical hemodynamics as a proxy of brain activity during physical exercise.

Sign in / Sign up

Export Citation Format

Share Document