EXTRACTION OF TANNIN, GALLIC ACID AND PYROGALLOL FROM AQUEOUS MEDIA WITH WATER-SOLUBLE POLYMERS AND THEIR DETERMINATION IN CONCENTRATES BY THIN-LAYER CHROMATOGRAPHY

For the first time water-soluble homo- and co-polymers based on N-vinylcaprolactam and N-vinylpyrrolidone were applied for the extraction of tannin, gallic acid and pyrogallol from the aqueous-salt solutions. The distribution coefficients and the degree of extraction of phenols were established. Extraction characteristics of phenols depend on their solubility, structure, and the number of functional groups in their molecules that can form hydrogen bonds and π-complexes with polymers. The large distribution coefficients of tannin are due to its high hydrophobicity. It was established that the copolymer of N-vinylpyrrolidone with N-vinylcaprolactam shows higher extraction efficiency than homopolymers. The efficiency of extraction of the studied phenols depends on the pH of aqueous solutions. The maximum degree of extraction of phenols was achieved at pH 3. Conditions of division and determination of phenols in the polymer-aqueous concentrate using the chromatography method in a thin layer were chosen. It has been established that the selective separation of the investigated phenols is achieved using a mobile phase of 1-butanol, acetic acid and chloroform in the ratio (vol.) 4 : 1 : 5. Eluent eliminates the blur spots.  Separation time of analytes is reduced from 60 to 20-30 min in comparison with known chromatographic systems. It was established that the nature of the polymer and its presence in the concentrate does not affect the chromatographic characteristics. The technique of determination of studied substances in aqueous media was developed.Keywords: polyphenols, tannin, gallic acid, pyrogallol, extraction, chromatography, water-soluble polymers, N-vinylpyrrolidone, N-vinylcaprolactam, copolymer(Russian)DOI: http://dx.doi.org/10.15826/analitika.2015.19.3.005 P.T. Sukhanov1, A.N. Il’yin1, E.V. Churilina1, G.V. Shatalov21Voronezh State University of Engineering Technologies, Voronezh, Russian Federation2Voronezh State University, Voronezh, Russian Federatio

EXTRACTION OF TANNIN, GALLIC ACID AND PYROGALLOL FROM AQUEOUS MEDIA WITH WATER-SOLUBLE POLYMERS AND THEIR DETERMINATION IN CONCENTRATES BY THIN-LAYER CHROMATOGRAPHY

For the first time water-soluble homo- and co-polymers based on N-vinylcaprolactam and N-vinylpyrrolidone were applied for the extraction of tannin, gallic acid and pyrogallol from the aqueous-salt solutions. The distribution coefficients and the degree of extraction of phenols were established. Extraction characteristics of phenols depend on their solubility, structure, and the number of functional groups in their molecules that can form hydrogen bonds and π-complexes with polymers. The large distribution coefficients of tannin are due to its high hydrophobicity. It was established that the copolymer of N-vinylpyrrolidone with N-vinylcaprolactam shows higher extraction efficiency than homopolymers. The efficiency of extraction of the studied phenols depends on the pH of aqueous solutions. The maximum degree of extraction of phenols was achieved at pH 3. Conditions of division and determination of phenols in the polymer-aqueous concentrate using the chromatography method in a thin layer were chosen. It has been established that the selective separation of the investigated phenols is achieved using a mobile phase of 1-butanol, acetic acid and chloroform in the ratio (vol.) 4 : 1 : 5. Eluent eliminates the blur spots.  Separation time of analytes is reduced from 60 to 20-30 min in comparison with known chromatographic systems. It was established that the nature of the polymer and its presence in the concentrate does not affect the chromatographic characteristics. The technique of determination of studied substances in aqueous media was developed.Keywords: polyphenols, tannin, gallic acid, pyrogallol, extraction, chromatography, water-soluble polymers, N-vinylpyrrolidone, N-vinylcaprolactam, copolymer(Russian)DOI: http://dx.doi.org/10.15826/analitika.2015.19.3.005 P.T. Sukhanov1, A.N. Il’yin1, E.V. Churilina1, G.V. Shatalov21Voronezh State University of Engineering Technologies, Voronezh, Russian Federation2Voronezh State University, Voronezh, Russian Federatio

Extraction of tannin, gallic acid and pyrogallol from aqueous media with water-soluble polymers and their determination in concentrates by thin-layer chromatography

Для экстракции танина, галловой кислоты и пирогаллола из водно-солевых растворов впервые применены водорастворимые гомо- и сополимеры на основе N-винилкапролактама и N-винилпирролидона. Установлены коэффициенты распределения и степень извлечения фенолов. Экстракционные характеристики фенолов зависят от их растворимости, строения, числа функциональных групп в их молекулах, способных образовывать водородные связи и π-комплексы с полимерами. Большие коэффициенты распределения таннина обусловлены его высокой гидрофобностью. Установлено, что сополимер N-винилпирролидона и N-винилкапролактама проявляет большую экстракционную способность по сравнению с гомополимерами. Эффективность экстракции исследуемых фенолов зависит от рН раствора. Максимальная степень извлечения фенолов достигается при рН = 3. Обоснованы условия разделения и определения фенолов в полимерно-водном концентрате методом хроматографии в тонком слое. Селективное разделение исследуемых фенолов проводили с применением подвижной фазы, состоящей из бутанола-1, уксусной кислоты и хлороформа в соотношении (об.) 4 : 1 : 5. Элюент исключает размывание пятен. По сравнению с известными хроматографическими системами время разделения аналитов уменьшается с 60 до 20-30 минут. Установлено, что природа полимера и его присутствие в концентрате не влияет на хроматографические характеристики. Разработан способ определения исследуемых веществ в водных средах.For the first time water-soluble homo- and co-polymers based on N-vinylcaprolactam and N-vinylpyrrolidone were applied for the extraction of tannin, gallic acid and pyrogallol from the aqueous-salt solutions. The distribution coefficients and the degree of extraction of phenols were established. Extraction characteristics of phenols depend on their solubility, structure, and the number of functional groups in their molecules that can form hydrogen bonds and π-complexes with polymers. The large distribution coefficients of tannin are due to its high hydrophobicity. It was established that the copolymer of N-vinylpyrrolidone with N-vinylcaprolactam shows higher extraction efficiency than homopolymers. The efficiency of extraction of the studied phenols depends on the pH of aqueous solutions. The maximum degree of extraction of phenols was achieved at pH 3. Conditions of division and determination of phenols in the polymer-aqueous concentrate using the chromatography method in a thin layer were chosen. It has been established that the selective separation of the investigated phenols is achieved using a mobile phase of 1-butanol, acetic acid and chloroform in the ratio (vol.) 4 : 1 : 5. Eluent eliminates the blur spots. Separation time of analytes is reduced from 60 to 20-30 min in comparison with known chromatographic systems. It was established that the nature of the polymer and its presence in the concentrate does not affect the chromatographic characteristics. The technique of determination of studied substances in aqueous media was developed

CORRELATION BETWEEN TUNNEL POSITION ACCORDING TO RADIOLOGICAL DATA AFTER ACL RECONSTRUCTION, SURGEON’S TUNNEL ESTIMATION DURING SURGERY AND ANTROPOMETRIC CHARACTERISTICS OF THE PATIENT

Purpose - to assess the correlation between tunnel position according to radiological data after ACL reconstruction and surgeon’s estimation during surgery. Material and methods. The study included 86 patients who underwent primary ACL reconstruction with the same surgeon and surgical technique in European Clinic of Sports Traumatology and Orthopedics between 2013 and 2015. In all cases hamstring autograft was used and patients received coronal and sagittal radiographs on the first day after surgery. Surgical data on tunnel position were obtained directly from the OR as dictated by the performing surgeon and fixed in the special registry. Radiological data were exported to eFilm, Merge Healthcare software for graphical analysis. Results. The study group included 54 male and 32 female patients, mean age 35.2 ±1,13, range from 17 to 56 years. Analysis of surgical data showed the median femoral tunnel angle on coronal plane to be 45° (IQR 45° - 60°), angle which occurred most often was 45°, median tibial tunnel angle on coronal plane appeared to be 30° (IQR 30° -35°), angle which occurred most often was 30°. According to radiological coronal plane data median femoral tunnel angle accounted 32° (IQR 28° -36°), angle which occurred most often was 35°, while median tibial tunnel angle accounted 20° (IQR 17-25°,) angle which occurred most often was 19°. Coronal plane mean tibial plateau width was 90,2±,1,1mm with tibial tunnel center located on the 48.55% from the medial side. Sagittal plane mean tibial plateau depth was 53,8 ± 0,6 mm with tibial tunnel center located on the 43.95% from the ventral side. Median tibial plateau posterior slope on the sagittal plane accounted 8° (IQR 6°-9°). Conclusion. Tunnel placement during arthroscopic ACL reconstruction could hardly be standardized. Anthropometric differences between patients can lead to different bone tunnel positions even if the procedure is performed by the same surgeon and surgical technique