Preparation of hydrophilic Indigo Naturalis based on polyethylene glycol( PEG) surface film-forming method and evaluation / 中国中药杂志

Polyethylene glycol (PEG) surface film-forming method was used to prepare hydrophilic Indigo Naturalis decoction pieces with stable effect.The preparation process of modified Indigo Naturalis was optimized and its microscopic properties,hydrophilicity,antipyretic efficacy,and safety were systematically evaluated.With equilibrium contact angle as assessment index,the influence of modifier type,modifier dosage,dispersant dosage,and co-grinding time on water solubility of Indigo Naturalis was investigated by single factor test.The results showed that the optimal preparation process was as follows.The 6%PEG6000 is dissolved in 10%anhydrous ethanol solution by sonification and then the mixture is ground with Indigo Naturalis for 2 min.The resultant product is dried on a square tray in an oven at 60℃to remove ethanol and thereby the PEG-modified hydrophilic Indigo Naturalis decoction pieces are yielded.The morphological observation under scanning electron microscope (SEM) indicated that the modified Indigo Naturalis had smoother surface than Indigo Naturalis,and energy spectrometer measurement showed that the nitrogen (N),calcium(Ca),oxygen (O),and silicon (Si) on the surface of modified Indigo Naturalis powder were less than those of Indigo Naturalis powder.Modified Indigo Naturalis had the equilibrium contact angle 18.96°smaller,polar component 22.222 m J·m~(-2)more,and nonpolar component 7.277 m J·m~(-2)smaller than the Indigo Naturalis powder.Multiple light scattering technique was employed to evaluate the dispersion in water and the result demonstrated that the transmittance of Indigo Naturalis and modified Indigo Naturalis was about85%and 75%,respectively,suggesting the higher dispersity of modified Indigo Naturalis.The suspension rate of modified Indigo Naturalis in water was determined by reflux treatment.The result showed that 57%of Indigo Naturalis was not wetted after refluxing for1 h,while the modified Indigo Naturalis was all wetted and dispersed into water.The dissolution of indigo and indirubin of modified Indigo Naturalis increased and the process was more stable.Then,rats were randomized into the blank group,model group,acetaminophen group,Indigo Naturalis group,and hydrophilic Indigo Naturalis group.The temperature changes of rats were observed after administration and the concentration of IL-1βand TNF-αin serum and IL-1βand PGE_2in hypothalamus was measured.The results indicated that the temperature of Indigo Naturalis group and hydrophilic Indigo Naturalis group dropped and the IL-1βlevel of the hydrophilic Indigo Naturalis group decreased (P<0.05) as compared with those in the model group.Thus,both Indigo Naturalis and hydrophilic Indigo Naturalis had antipyretic effect,particularly the hydrophilic Indigo Naturalis.The acute toxicity test of hydrophilic Indigo Naturalis verified that it had no toxicity to rats.In this study,the hydrophilic Indigo Naturalis decoction pieces were prepared with the PEG surface film-forming method,and the antipyretic efficacy and safety were evaluated,which expanded the technological means of powder modification for Chinese medicine and provided a method for clinical use of Chinese medicine.

Investigating key influencing factors of low wettability of Indigo Naturalis based on component “knockout method” combined with surface property analysis / 中草药

Objective: To explore the key factors affecting the low wettability of Indigo Naturalis by using “knockout” method combined with surface element analysis, so as to provide scientific basis for regulating and changing the wettability of Indigo Naturalis. Methods: Using N,N-dimethylformamide as solvent, six Indigo Naturalis powders were prepared by ultrasonic extraction for 0-5 times, 30 min for each time, filtration and drying process. The contents of indigo and indirubin in six kinds of Indigo Naturalis were determined by HPLC. The contact angle, surface free energy and its components, particle size, surface morphology, surface element analysis and infrared spectroscopy were determined. The relationship between the content of organic matter and wettability of Indigo Naturalis was discussed by correlation analysis. Results: With the increase of extraction times, the content of indigo decreased from 3.320% to 0.112%, the content of indirubin decreased from 0.120% to 0.006%, the contact angle in pure water decreased from 53.56 degrees to 34.84 degrees, the polar component of surface free energy increased from 24.880 to 38.701 mJ/m2, the non-polar component changed little, and the total surface free energy increased from 46.523 to 62.240 mJ/m2. Scanning electron microscopy (SEM) showed that the particulate matter on the surface of Indigo Naturalis was gradually disappeared, and the surface became smooth; Mapping scanning by energy spectrometer showed that N element was gradually decreased, Ca and Si element were increased slightly; Particle size distribution and infrared spectrum changed little; Correlation analysis showed that the content of indigo, indigo and indirubin was positively correlated with the contact angle, and the higher the content, the worse the wettability. Conclusion: The contact angle, polar component of surface free energy and total surface free energy of Indigo Natural was significantly increased after knockout, and the wettability was increased. Organic substances adhering to the surface of Indigo Naturalis were the key factors leading to its low wettability. To improve the hydrophilicity of Indigo Naturalis by powder surface modification technology, it is necessary to focus on organic substances.

Fabrication of hydrophilic medical catheter with hydrogel grafting and the in vivo evaluation of its histo-compatibility / 生物医学工程学杂志

The biocompatible hydrogel was fabricated under suitable conditions with natural dextran and polyethylene glycol (PEG) as the reaction materials. The oligomer (Dex-AI) was firstly synthesized with dextran and allylisocyanate (AI). This Dex-AI was then reacted with poly (ethyleneglycoldiacrylate) (PEGDA) under the mass ratio of 4∶6 to get hydrogel (DP) with the maximum water absorption of 810%. This hydrogel was grafted onto the surface of medical catheter via diphenyl ketone treatment under ultraviolet (UV) initiator. The surface contact angle became lower from (97 ± 6.1)° to (25 ± 4.2)° after the catheter surface was grafted with hydrogel DP, which suggests that the catheter possesses super hydrophilicity with hydrogel grafting. The evaluation after they were implanted into ICR rats subcutaneously verified that this catheter had less serious inflammation and possessed better histocompatibility comparing with the untreated medical catheter. Therefore, it could be concluded that hydrogel grafting is a good technology for patients to reduce inflammation due to catheter implantation, esp. for the case of retention in body for a relative long time.

Study on the Effect of Hydrophilic/Hydrophobic Nano-silica with Different Adding Amount on the Stability of Glycyrrhetinic Acid Lipo-emulsion / 中国药房

OBJECTIVE:To study the effect of hydrophilic/hydrophobic nano-silica with different adding amount on the stabili-ty of lipo-emulsion. METHODS:Glycyrrhetinic acid lipo-emulsion 4 mL was taken,respectively adding into 0.5%,1.0%,1.5%(m/m,the same below) hydrophilic nSiO2,and 0.4%,0.75,1.0% hydrophobic nSiO2,incubating 2 h in 30 ℃ water;the same batch of Glycyrrhetinic acid lipo-emulsion was treated as blank control. The forms were observed under electron microscopy after treatment,absorbance value was determined,the stability parameter (KE) was calculated according to the absorbance value,then the adding amount of nSiO2 was optimized,3 batches of preparations was prepared,and the verification test was conducted. RE-SULTS:The spherical structure was Glycyrrhetinic acid lipo-emulsion in the electron microscopy,the substance wrapping its sur-face white ring (fully wrapped) or semi-circular structure (not fully wrapped) was nSiO2. KE of hydrophilic nSiO2 were 4.66%, 5.01% and -2.08%,and KE of hydrophobic nSiO2 were 3.02%,4.51% and 7.24%. The optimized adding amount of hydrophilic nSiO2 was 0.2%,0.3% and 0.4%,hydrophobic nSiO2 was 0.1%,0.2% and 0.3%;KE were 6.19%,3.05%,7.84%,8.42%, 2.41%,2.93%,respectively. The optimal adding amount was 0.3% hydrophilic nSiO2 and 0.2% hydrophobic nSiO2;the 3 batches of preparation showed the optimum stability in its own adding amount. CONCLUSIONS:Both hydrophilic and hydrophobic nSiO2 can improve the stability of Glycyrrhetinic acid lipo-emulsion,and preferably 0.3%,0.2%.

Optimization of modifiers and process for changing superficial hydrophilicity of Indigo Naturalis / 中草药

Objective: To discuss the interaction between modifier and Indigo Naturalis by selecting the modifier that enhancing the superficial hydrophilicity of I. naturalis, then the best powder modification technique was selected to prepare the hydrophilic decoction pieces of I. naturalis, which can suit for decoction. Methods: In this paper, the contact angle was used to select the modifier, thermal stability was studied by different drying temperatures; Mechanism and thermal stability were studied according to the microstructure of alcohols, I. naturalis, and indirrubin preliminarily. Best technique was chosen by single factor experiment and uniform design. Results: Alcohols could enhance the superficial hydrophilicity of I. naturalis comparing to the normal one, the acts of -OH and -CH3 were different, and generally, the modifying effect of longer carbochain and polyhydroxy-alcohol was better. The best modifier was ethanol, the optimum modifying technique was 19% ethanol and grinding for 23 min. Conclusion: Above all, alcohols can enhance the superficial hydrophilicity of I. naturalis, the use of ethanol as modifier and the modifying process are reliable and suitable, and hydrophilic decoction pieces of I. naturalis can be prepared successfully.

Prospective randomized clinical trial of hydrophilic tapered implant placement at maxillary posterior area: 6 weeks and 12 weeks loading

PURPOSE: Early loading of implant can be determined by excellent primary stability and characteristic of implant surface. The implant system with recently improved surface can have load application 4-6 weeks after installing in maxilla and mandible. This study evaluated the effect of healing period to the stability of hydrophilic tapered-type implant at maxillary posterior area. MATERIALS AND METHODS: This study included 30 patients treated by hydrophilic tapered-type implants (total 41 implants at maxilla) and classified by two groups depending on healing period. Group 1 (11 patients, 15 implants) was a control group and the healing period was 12 weeks, and Group 2 (19 patients, 26 implants) was test group and the healing period was 6 weeks. Immediately after implant placement, at the first impression taking, implant stability was measured using Osstell Mentor. The patients also took periapical radiographs after restoration delivery, 12 months after restoration and final followup period. The marginal bone loss around the implants was measured using the periapical radiographs. RESULTS: All implants were survived and success rate was 97.56%. The marginal bone loss was less than 1mm after 1 year postoperatively except the one implant. The stabilities of the implants were not correlated with age, healing period until loading, insertion torque (IT), the diameter of fixture and the location of implant. Only the quality of bone in group 2 (6 week) was correlated with the stability of implant. CONCLUSION: Healing period of 6 weeks can make the similar clinical prognosis of implants to that of healing period of 12 weeks if bone quality is carefully considered in case of early loading.

Preparation and properties of polydopamine coating on the surface of C/C composites / 军事医学

Objective Carbon/carbon ( C/C) composites are a potential material for bone repair .To improve the hydrophilicity and biological activity of C/C composites , polydopamine coating was prepared on the surface of C /C composites.Methods By changing the coating time and coating environment ( oxygen or air atmosphere ), a series of polydopamine coating samples were prepared . The water contact angle test , scanning electron microscope , energy dispersive spectrometer , atomic force microscope and protein adsorption test were used to characterize the properties of different samples.Then, the data were analyzed to optimize preparation conditions .Results When the concentration of dopamine was 2.0 g/L,and the coating time was 30 min (oxygen atmosphere) +11.5 h (air atmosphere), the water contact angle was decreased from 64.0°(blank sample) to 25.9°, suggesting that the hydrophilicity was improved greatly . The results of the scanning electron microscope , energy dispersive spectrometer and atomic force microscope showed that the coating was uniform and dense .The amount of protein adsorption per sample was 0.2817 mg.Conclusion The polydopamine coating on the C/C composites improves its hydrophilicity and biological activity , which indicates that the polydopamine coated C/C composites will be a new potential material for bone tissue repair .

Rupture distance of liquid bridge based on Surface Evolver simulation / 医用生物力学

Objective To study the variation of rupture distance of liquid bridge with different liquid volume, spherical radius and solid-liquid contact angle. Methods The process of stretching and rupture of liquid bridge between a sphere and a plane was simulated by Surface Evolver program. The rupture distance of liquid bridge which depended on the liquid volume, radius of sphere and wetting property of surface was calculated from the simulation. Results The theoretical formula of rupture distance which was related to the liquid volume, spherical radius and contact angle was derived based on the formula given by Lian and Willett, et al. The simulation result was in agreement with the theoretical result when the solid surface was hydrophilic (error <4.3%); when the solid surface was hydrophobic, the error between the simulation and theoretical results showed to be greater with the hydrophobicity enhanced. Conclusions The quasi-static process of stretching and rupture of liquid bridge can be well simulated by Surface Evolver program and the rupture distance can be given accurately from the simulation result. The error between the simulation and theoretical results in rupture distance on the hydrophobic surface appeared significantly increasing, because the formula given by Lian and Willett, et al was derived from data based on the hydrophilic surface.

Effect of etched microgrooves on hydrophilicity of titanium and osteoblast responses: A pilot study

PURPOSE: The aim of this pilot study was to investigate the effect of etched microgrooves on the hydrophilicity of Ti and osteoblast responses. MATERIAL AND METHODS: Microgrooves were applied on Ti to have 15 and 60 micrometer width, and 3.5 and 10 micrometer depth by photolithography, respectively. Further acid etching was applied to create Ti surfaces with etched microgrooves. Both smooth- and acid-etched Ti were used as the controls. The hydrophilicity of Ti was analyzed by determining contact angles. Cell proliferation and osteogenic activity of MC3T3 mouse preosteoblasts were analyzed by bromodeoxyuridine assay and alkaline phosphatase (ALP) activity test, respectively. One-way ANOVA, Pearson's correlation analysis and multiple regression analysis were used for statistics. RESULTS: Etched microgrooves significantly increased the hydrophilicity of Ti compared to the smooth Ti. 60 micrometer-wide etched microgrooves significantly enhanced cell proliferation, whereas the osteogenic activity showed statistically non-significant differences between groups. Result of the osteogenic activity significantly correlated with those of hydrophilicity and cell proliferation. Hydrophilicity was determined to be an influential factor on osteogenic activity. CONCLUSION: This study indicates that increase in hydrophilicity of Ti caused by etched microgrooves acts as an influential factor on osteogenic activity. However, statistically non-significant increase in the ALP activity suggests further investigation.

Effect of relative humidities on microstructural, barrier and mechanical properties of Yam starch-monoglyceride films

The effect of monoglyceride on microstructural, barrier and mechanical properties of casted yam starch films were investigated in different relative humidities (RH) and compared with glycerol-starch films. A single screw extruder was used to produce the starch - monoglyceride complex before film production and this process was effective to inhibit the phase separation in films. The addition of the hydrophobic compound reduced hydrophobicity, transparency and water vapor permeability of films. This later value for starch-glycerol film (1.7 x 10-10 g Pa-1 s-1 m-1) was higher than starch (1.2 x 10-10 g Pa-1 s-1 m-1) and monoglyceride-starch films (1.0 x 10-10 g Pa-1 s-1 m-1). Films containing glycerol had higher relative crystallinity (B and V H) with a slight increase at higher RH values, while for monoglyceride films, the crystallinity was constant. Monoglyceride-starch films presented poor mechanical properties when compared to glycerol- starch ones but they presented a stable behavior under different relative humidities.

Estudou-se o efeito da adição de monoglicerídeo nas propriedades microestruturais, mecânicas e de barreira de filmes de amido de inhame, em diferentes umidades relativas (UR), comparando-as com as de filmes de amido- glicerol. Uma extrusora mono-rosca foi usado para produzir o complexo amido-monoglicerídeo, antes de produzir o filme, e o processo foi efetivo para inibir a separação de fases que geralmente ocorre nesse tipo de filmes. A adição de monoglicerídeo, que é um composto hidrofóbico, reduziu a hidrofilicidade, a transparência e a permeabilidade ao vapor de água dos filmes. O valor desta, para os filmes de amido-glicerol (1,7 x 10-10 g Pa-1 s-1 m-1) foi maior que para os de amido (1,2 x 10-10 g Pa-1 s-1 m-1) e para os de amido-monoglicerídeo (1,0 x 10-10 g Pa-1 s-1 m-1). Os filmes com glicerol tiveram maior cristalinidade relativa (B e V H), com um ligeiro aumento em altas UR, enquanto que nos filmes com monoglicerídeo a cristalinidade foi constante. Os filmes de amido-monoglicerídeo apresentaram piores propriedades mecânicas que os filmes de amido-glicerol, mas foram mais estáveis sob diferentes umidades relativas.

Hydrophilicity and antigenicity of proteins—A case study of myoglobin and hemoglobin.

Hydrophilicity index is used to locate antigenic determinants on two related groups of proteins—myoglobin and hemoglobin. The data on 41 species (including 34 mammals) of myoglobin show that average hydrophilicity for the complete myoglobin molecules as well as the average hydrophilicity for all hydrophilic regions put together seem to remain constant; the variation in the size and location of the antigenic determinants in these species is very small indicating that the antigenic sites are not shifted during evolution. In the case of both the proteins there is a good agreement between the antigenic sites picked up by using hydrophilicity index and the experimentally determined antigenic sites. The data on 56 species of hemoglobin α-chains and 44 species of hemoglobin β-chains showed that although there are few sites on hemoglobin which have remained invariant during evolution, there is a significant variation in other sites in terms of either a splitting of a site, or a drastic change in the hydrophilicity values and/or a length of the site. Comparison of the hydrophilicity data on these two groups of proteins suggests that hemoglobins which perform a variety of functions as compared to myoglobins are evolving faster than myoglobins supporting the contention of earlier workers.