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Radiofarmaceutici bazirani na različitim molekulima obeleženimitrijumom-90, se koriste pri tretmanu neoperativnih vrsta tumora, kao i u radijacionoj sinovektomiji. Veliko interesovanje za korišćenje 90Y u terapeutske svrhe potiče zbog njegovih nuklearnih karakteristika (t1/2=64,1, Eβ,max= 2,3 MeV,bez emisije  zračenja). Dostupnost 90Y sa vrlo niskom radiohemijskom kontaminacijom je od suštinske važnosti u terapeutskoj primeni.Postojanje dugoživućeg pretka 90Sr sa vremenom poluživota od 28,9 godina i kratkoživućeg potomka 90Y nam omogućavaju formiranje generatorskog sistema. Iako postoje nekoliko vrsta generatora, prema literaturnim podacima, elektrohemijski generatori i generatori zasnovani na tečnim membranama imaju najveću perspektivu.Membranska ekstrakcija se takođe naziva i pertrakcija i bazirana je natrofaznom sistemu sa organskom fazom (tečna membrana) koja se nalazi između dve vodene faze i predstavlja alternativnu metodu klasičnoj tečno-tečnoj ekstrakciji. Prema literaturnim podacima, koristi se za razdvajanje širokog opsega rastvorenih supstanci uključujući biološke molekule, metalne jone, organske zagađivače i radionuklide.Elektrohemijska metoda je predložena kao rešenje pri separaciji 86Y od 86Sr i dobijanje 86Y koji služi pri pozitronsko emisionoj tomografiji (PET).Literaturni podaci pokazuju da elektrohemijska separacija predstavlja dobro rešenje jer omogućava veliku efikasnost uz minimalnu kontaminaciju okolnog prostora.Radiofarmaceutici koji se koriste u terapiji su u hemijskom smislukompleksna jedinjenja u kojima se kao centralni joni javljaju radioaktivni izotopi metala sa  ili  raspadom, dok su ligandi organski molekuli koji su sposobni da stvaraju helate. Ovi molekuli pored toga što su helatori za radiometal imaju i ulogu da se vežu za biomolekul. Zbog toga se i nazivaju bifunkcionalni helatori. Najpoznatiji i do sada najviše korišćeni bifunkcionalni helatori u radiohemiji itrijuma su: 1,4,7,10-tetraazociklododekan-1,4,7,10-tetraacetatna kiseli, The subject of this dissertation was biospeciation of Y(III) ion in human blood plasma. To this end characterization of complexation equilibria of Y3+ with DTPA, DOTA and ciprofloxacine and production of yttrium-90 from Sr/Y generator was made.Hydrolysis and complexation of yttrium were investigated using potentiometricmesurenment with glass electrode in 0.15 mol dm-3 NaCl ionic medium, at 310.0 ± 0.5 К. In addition, data of the hydrolysis of yttrium (III) ion and complexation of yttrium (III) ion with DTPA and DOTA were obtained by ESI MS technique. Morphologies of various kinds of yttrium-hydroxide precipitates were examined using a scanning electron microscopy. Precipitates were also analyzed by thermogravimetric analysis (TGA) and infrared spectroscopy using KBr pill technique. Computer modeling May model was used for the determination of yttrium species in human plasma and certain dominant yttrium complexes with small molecules. The second part of the Thesis relate to the separation of90Y from 90Sr with high radiochemical yield and purity, that can be used for labelling organic molecules (DTPA and DOTA) which are used in nuclear medicine.The obtained results can be sumarized as follows: The stability constants of hydrolitic complexes (log β,.q) were: Y(OH)2+ (log β1,-1 = -7.71 ± 0.05), Y(OH)2+ (log β1,-2 = -16.42 ± 0.03), Y(OH)3 (log β1,-3 = -26.01± 0.03),Y2(OH)2 4+(log β2,-2 = -14.23± 0.05), Y3(OH)54+ (log β3,-5 = -34.20 ± 0.07) иY4(OH)66+(log β4,-6 = -37.10 ± 0.08). Hydrolytic species determined by potentiometric method were confirmed by ESIMS method also. Hydrolytic species containing tetramer ions with high charges were: [Y4(OH)4(H2O)2]8+, [Y4(OH)2Cl2]8+ и [Y4(OH)3ClH2O]8+. The hydrolytic precipitation reactions with NaOH or urea as precipitating agents were studied. The obtained precipitates were characterized by the X-ray diffraction, the SEM technique, thermal analysis (TG-DSC) and infrared spectroscopy. Powder X-ray diffraction (XRD) characterization

In this study, tin fluoride colloid (SnF-c) was prepared, labeled with yttrium-90 (90Y), and characterized with respect to its physicochemical properties and biological behavior in an animal model. Particle size of SnF-c, at constant concentration of SnF2, was dependent on pH, concentration of sodium fluoride (NaF), temperature, and time. The particle size of SnF-c decreased with an increase in NaF concentration and a decrease in reaction mixture pH. Radiolabeling yield of 90YSnF-c at higher temperature increased and it was greater than 98% for the preparation at 95 degrees C. The 90YSnF-c demonstrated high in vitro stability both in human serum and human synovial fluid at 37 degrees C up to 7 days. In vivo distribution studies in healthy male Wistar rats of 90YSnF-c (particles LT 1 mu m), following intravenous administration, revealed that the localization takes place preferably in the liver. The 90YSnF-c (particles GT 1 mu m) was well retained in the synovial space for 96 h after intra-articular injection, whereas leakage of 90Y from the joint was 1.96% over this period. Because of high labeling yield and stability, 90YSnF-c might be a promising agent for radiosynovectomy or therapy of liver malignancies. (C) 2012 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:21942203, 2012

Radiopharmaceuticals based on Y-90 are widely used in the treatment of malignant deseases. In order to meet the requirements for their future application, a Sr-90/Y-90 generator was developed and 90Y eluted from this locally produced generator was used for the radiolabelling of the DOTA-conjugated somatostatin analog [DOTA(0),Tyr(3)] octreotate and the preparation of [Y-90-DOTA(0),Tyr(3)] octreotate (Y-90-DOTATATE) for peptide receptore radionuclide therapy. Sr-90/Y-90 generator was based on the electrochemical separation of Y-90 from Sr-90 in a two-cycle electrolysis procedure. Three electrode cells were used to perform both electrolyses. In both cycles, working electrodes were kept on constant potential. The pH of the solution was adjusted to 2.7 of the value before the electrolyses. The radionucliclic purity of the Y-90 solution was analysed by ITLC and extraction paper chromatography. The labelling of peptide (100 mu g DOTATATE) with (YCl3)-Y-90 was performed at 95 degrees C for 30 minutes. Radiochemical purity was determined by HPLC and chromatographic separation, using a solid SepPak C-18 column. Results obtained confirmed the efficiency of our electrochemical separation technique and quality control methods for Y-90. The achieved efficiency of the Sr-90/Y-90 generator above 96% of the theoretical value represents a good basis for the further development of this generator. The labelling of the DOTATATE with Y-90 exhibited a high efficiency, too: there was less than 1% of Y-90(3+) in the Y-90-DOTATATE.

Two rhenium(I) tricarbonyl complexes with the tridentate monoanionic NSO ligands, 4-(benzimidazol-2-yl)-3-thiabutanoic acid (complex 3) and [1-(11-carboxyundecanyl)-4-(benzimidazol-2-yl)]-3-thiabutanoic acid (complex 4) were synthesized and characterized by spectroscopic methods and elemental analysis. X-ray crystallographic analysis of complex 3 revealed a distorted octahedral geometry around rhenium defined by the three facially bound CO groups and the NSO donor atom set of the tridentate ligand. The analogous technetium-99m complexes (complexes 5 and 6) were also prepared quantitatively by reaction of the NSO ligands with the fac-[Tc-99m(H2O)(3)(CO)(3)](+) synthon and their identity was established by chromatographic comparison to their rhenium congeners. Biodistribution in mice of complex 6 bearing the fatty acid chain showed significant heart uptake (6.26 +/- 0.79% ID/g p.i.) at 1 min accompanied, however, with a heart: blood ratio below 1. (C) 2011 Elsevier B. V. All rights reserved.

Two rhenium(l) tricarbonyl complexes, with the monoanionic tridentate NSO type ligand, 4-(imidazolin-2-yl)-3-thiabutanoic acid and 4-(N-ethylimidazolin-2-yl)-3-thiabutanoic acid were synthesized and isolated in pure form. Both complexes were characterized by spectroscopic methods and elemental analysis. The solid-state structure of 4-(imidazolin-2-yl)-3-thiabutanoic acid and of both complexes was established by X-ray crystallography. The geometry about the rhenium is octahedral. The analogous technetium-99m complexes were also prepared quantitatively by the reaction of both ligands with the fac-[(99m)Tc(CO)(3)(H(2)O)(3)](+) synthon and their identity was established by chromatographic comparison to their rhenium congeners. (C) 2009 Elsevier Ltd. All rights reserved.

Introduction: The aim of this study was to find out if Y-90 could form a stabile complex with meso-2,3-dimercaptosuccinic acid (DMSA) and if Y-90-DMSA may have potential for tumor therapy in the palliative treatment of bone metastases. Methods: The preparing of Y-90-DMSA was carried out by varying experimental parameters, such as ligand concentration, pH, time, and temperature of the reaction, in order to maximize the labeling yield. Analysis of the complexes enclosed the radiochemical quality control (instant thin-layer chromatography, paper chromatography, and high-performance liquid chromatography), determination of pharmacokinetical parameters as well as biodistrbution study in health male Wistar rats. In vitro stability of the complexes was tested too. Results: Y-90-DMSA could be prepared in high yields ( GT 95%) under optimized conditions of reaction. Stability studies in saline and human serum in vitro showed no significant release of activity from the ligand over 24 hours and 10 days, respectively. The preliminary biodistribution results in rat at 2 hours indicated that Y-90-DMSA, at both pH levels, was significantly retained into bone. The uptake in the kidneys was lower for Y-90-DMSA at pH 8.0 then at pH 3.0. The retention in other organs was negligible. Conclusions: Y-90 complexes could be made with ease with DMSA. Y-90-DMSA was obtained in good yield and was found to be very stable. A promising biodistribution result of this complex pointed at potential in the palliative treatment of bone metastases.

Objective Tc-99m-p-aminohippuric acid (PAH) is a new radiopharmaceutical rapidly secreted by the kidneys in a manner consistent with tubular secretion. A comparative study of renal scintigraphy and clearance with Tc-99m-PAH, diethylene triamine pentaacetic acid (DTPA) and mercaptoacetyltriglycine (MAG(3)) was performed. Methods (TC)-T-99m-PAH was prepared from a lyophilized kit by addition of sodium pertechnetate in the presence of DTPA. Ten healthy individuals were injected with 110 MBq of Tc-99m-PAH. A dynamic study was repeated with Tc-99m-DTPA and Tc-99m-MAG(3) several days later, after a 1-day interval. Clearance measurements were performed in five individuals. Results The mean values of time-to-peak activity (T-max) and the time from peak to 50% of peak activity (T-1/2) for Tc-99m-PAH (3.6 +/- 0.9 and 6.9 +/- 2.7 min, respectively) and Tc-99m-MAG, (3.5 +/- 0.8 and 6.8 +/- 2.1 respectively) were significantly lower in comparison with those of Tc-99m-DTPA (4.9 +/- 1.7 and 11.7 +/- 1.9 min, respectively). The mean value of Tc-99m-PAH clearance (186.9 +/- 12.2 ml/min) was significantly lower in comparison with MAG(3) clearance (303.9 +/- 19.5 ml/min) and significantly higher than DTPA clearance (85.0 +/- 24.1 ml/min). Conclusion Our preliminary results indicate the potential usefulness of Tc-99m-PAH for routine renal scintigraphy. Owing to its fast kinetics, excretion and high-quality images, it could be a suitable for Tc-99m-DTPA. Tc-99m-PAH clearance values, however, were significantly lower than those of MAG(3), and could not be used for the estimation of renal plasma flow. Nucl Med Commun 30:76-81 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams and Wilkins.

Colloidal particle size is an important characteristic to consider when choosing a radiopharmaceutical for diagnosis and therapeutic purposes in nuclear medicine. Photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM) were used to determine the particle-size distribution of (90)Y- and (99m)Tc-labelled antimony trisulfide (Sb(2)S(3)) and tin colloids (Sn-colloid). (90)Y-Sb(2)S(3) and (99m)Tc-Sb(2)S(3) were found to have a diameter of 28.92 +/- 0.14 and 35.61 +/- 0.11 nm, respectively, by PCS. By TEM, (90)Y-Sb(2)S(3) particles were measured to be 14.33 +/- 0.09 nm. (90)Y-labelled Sn colloid were found to exist with a d(v(max1)) of 805 nm and a d(v(max2)) of 2590 nm, by PCS, whereas (99m)Tc-Sn colloid was shown to have more than 80% of radioactive particles of approximately 910 nm by PCS. For (90)Y-labelled Sb(2)S(3) and Sn colloid, a comparison of TEM and PCS indicates that these techniques found significantly different mean diameters. TEM has an excellent resolution necessary for radiocolloid particle-sizing analysis, and it is a desirable size-measuring technique because it is more reliable than PCS.

The goal of this investigation was to examine the possibilities for yttrium-90-labeling of the 2,3-dicarboxypropane-1,1-diphosphonic acid (DPD), which is currently labeled with technetium-99m and as a Tc-99m-DPD clinically used as bone imaging agent. Analysis of the complex enclosed the radiochemical quality control methods, biodistribution studies, as well as the determination of pharmacokinetic parameters. The biological behavior of complexes Y-90-DPD, Tc-99m-DPD and Y-90-labeled DPD-kit formulation [Y-90-(Sn)-DPD] in animal model was compared. The labeling conditions were standardized to give the maximum yield, which ranged between 93% and 98%. The examined Y-90 complex could be easily prepared, with an outstanding yield and was also found to be very stable for at least 10 h after Y-90-labeling. Protein binding value was 4.6 +/- 0.7% for Y-90-DPD complex and the complex possess a hydrophilic character. The satisfactory results of Y-90- DPD biodistribution in healthy test animals were obtained; the uptake in the bone was 11-13% ID/g after 24 h depending on the pH value during the preparation. With high skeletal uptake, a minimum uptake in soft tissues and rapid blood clearance the Y-90-DPD complex proved to be an excellent candidate for targeting tumor therapy. (C) 2008 Elsevier Ltd. All rights reserved.

The Tc-99m-labelling of the amino acids tyrosine (Tyr) and lysine (Lys), fundamental building blocks of proteins and peptides, as well as biological properties of the labelled compounds are investigated. Three different approaches for the labelling with Tc-99m have been investigated: direct reduction with stannous tin in the presence of the amino acids, the preformed chelate approach through polydentate chelates DTPA and GH, and the organometallic approach using [Tc-99m(CO)(3)(H2O)(3)](+) precursor. The direct labelling approach was not successful and the yield was poor. In the presence of DTPA and GH, the labelling efficiency was between 43.6 and 97.8%, depending on the amino acid and the polydentate chelate. The use of [Tc-99m(CO)(3)(H2O)(3)](+) precursor point at the formation of Tc-99m(l) co-ordinated complexes with high yield. In this approach, pH and heating influenced the yields. The results of organ distribution study for [Tc-99m(Tyr)(H2O)(CO)(3)] and [Tc-99m(Lys)(H2O)(CO)(3)] show accumulation in liver, kidneys and intestine., Copyright (C) 2007 John Wiley and Sons, Ltd.

The biological behavior of fullerene derivatives shows their considerable potential for medical application. Polyhidroxilated, water soluble fullerenol C-60(OH)(22). used in these studies, was synthesized by procedure complete substitution of bromine atoms from polybromine derivatives C60Br24 in alkaline media. In order to investigate the pharmacological behaviour and metabolism of the fullerenol, quickly and conveniently, we present the way and possibilities for its labelling with Tc-99m (T-1/2=6.02h, E-n=141keV), which bind to the outside, leaving the cage intact. Two different labelling approaches with technetium-99m were performed: direct labelling by tin (II) chloride method and labelling with Tc-99m(I) using [Tc-99m(CO)(3)(H2O)(3)](+) precursor. The radiochemical studies results have shown that content of free (TcO4-)-Tc-99m in the samples was depend on fullerenol-stannous chloride ratio and increased if ratio was higher. HPLC quality control results of Tc-99m(CO)(3)-[C-60(OH)(22)] have shown that the labelling yield, in alkaly media, was 95.35%. Protein binding to HA was species-dependent process. The biological behaviour of labelled fullerenol were different in dependence of labelling method and the time of sacrificed of animals. From recent investigations it can be concluded that oxidation state in technetium coordination complexes has a great impact on in vitro and in vivo behaviour of the these complexes.

Resorcinol-formaldehyde (RF) cryogels were synthesized by sol-gel polycondensation of resorcinol with formaldehyde and freeze-drying carried out with t-butanol. Carbon cryogels were obtained by pyrolyzing RF cryogels in an inert atmosphere. Characterization by nitrogen adsorption showed that carbon cryogels were micro- and mesoporous materials with high surface areas (500 m(2)/g LT S-BET LT 700 m(2)/g). Cyclic voltammetry experiments at various scan rates (2 to 200 mV s(-1)) were carried out to study the electrical double-layer charging of carbon cryogel electrodes in 0.5 mol dm(-3) HClO4 solution. It has been demonstrated that the total specific capacitance can further be divided into mesoporous and microporous specific capacitance by analyzing the linear dependence of the specific capacitance (C) on the reciprocal of the square root of the potential scan rate (nu(-1/2)), as well as linear dependence of the reciprocal specific charge (1/C) on the square root of the potential scan rate (nu(1/2)).

Resorcinol-formaldehyde (RF) cryogels were synthesized by the sol-gel polycondensation of resorcinol (R) with formaldehyde (F) and freeze-drying was carried out with t-butanol. Carbon cryogels were obtained by pyrolyzing RF cryogels in an inert atmosphere. Characterization by nitrogen adsorption showed that the carbon cryogels were micro and mesoporous materials with high specific surface areas (S-BET approximate to 550 m(2)/g). Cyclic voltammetry experiments at various scan rates (2 to 200 mV s(-1)) were performed to study the electrical double-layer charging of carbon cryogel electrodes in 0.5 mol dm(-3) HClO4 solution. It has been demonstrated that it is possible to sub-divide the total specific capacitance into the mesoporous and the microporous specific capacitance by analyzing the linear dependence of the charge (q) on the reciprocal of the square root of the potential scan rate (v(-1/2)), and the linear dependence of the reciprocal charge (l/q) on the square root of the potential scan rate (v(-1/2)). The specific capacitance was found to be constant over a wide range of sample weight (12.5 to 50.0 mug) and a very promising specific capacitance value of 150 F/g, was found for this material operating in an acidic 0.5 mol dm(-3) HClO4 solution at room temperature.

The complex equilibrium in tin (II)-p-aminohippuric acid (PAH) solutions in perchlorate medium was investigated. The interaction between Sn (II)-ion and PAH was studied with the purpose to establish whether PAH could form complex with, Sn (II)-ion during the labeling with technetium-99m. HPLC, spectrophotometric and pH-metric methods were used. Dissociation constants of PAH, thermodynamic parameters of PAH dissociation, as well as stability constant of tin (II)-PAH were determined. The values of thermodynamic dissociation constants of PAH were 4.25, 4.19 and 4.15 at 295, 302 and 310 K respectively. The calculated thermodynamic values DeltaGdegrees, DeltaHdegrees and DeltaSdegrees, were -24.01 KJ mol(-1), -12.44 KJ mol(-1) and 39.22 Jmol(-1) K-1 at 295 K respectively. Sn (II)-ion exhibits only a weak interaction with PAH in the pH range 2.0 divided by 3.7, e.g. in the Sn-PAH solution a weak complex with high degree of dissociation was obtained. The treatment of spectral data referring to Sn-PAH solutions indicates the formation of a mononuclear complex [SnPAH](+). Mathematical analysis of experimental data indicated that the best fit of the potentiometric data was achieved by assuming the formation of a mixed hydrolytic complex [Sn(OH)PAH]. The calculated value of the stability constant was: log beta(1,-1.1) = 0.95 +/- 0.11 at 298 K.

A new procedure for the aggregation of human albumin and Tc-99m-labelling of the prepared macroaggregated albumin are presented. Simple methods for quantifying of all the radiochemical impurities existing in Tc-99m-MAA were tested. Thus, 85% methanol was used as the mobile phase in paper and ITL chromatography with Whatman N-o 1 and ITLC-SA strips. A system of two solvents (acetone and 1 M NaCl or 0.9% NaCl) was used for 3 MM paper, ITLC-SA and ITLC-SG strips and silica gel plates as the stationary phase. Low-voltage paper electrophoresis with Whatman 3 MM paper sheets soaked in barbiturate buffer and the gel chromatography column method (Sephadex G-25) were also applied. Filtration through syringe filters, proposed by European and Yugoslav Pharmacopoeia, was performed for comparison. The application of the mentioned tests lead to consistent results for the labelling efficiency ( GT 98.5%) and percent radiochemical impurities of Tc-99m-MAA. Determination of the particles number in a counter chamber and their size distribution under a light microscope with a calibrated ocular scale gave the result of 300000-350000 particles per 1 mg of HA. This confirmed that the human albumin macroaggregates prepared by our new procedure is remarkably improved and convenient for routine diagnostic purposes.

Tc-99m-Hipp as a modified Tc-99m-DTpA, and Tc-99m-PAH as a new renal agent are developed. Each veal of lyophilised kit contain hippuric (Hipp) or p-aminohippuric acid (PAH), diethyltriaminepentaacetic acid as calciumtrisodium salt (CaNa(3)DTPA) and stannouschloride (SnCl2. xH(2)O), in molar ratio Hipp/PAH:DTPA = 4:1. They are high radiochemical purity radiopharmaceuticals, with hydrophilic character and low percentage of protein binding. The ITL chromatography and HPLC analyses of these labeled compounds have shown almost identical results as Tc-99m-DTPA, but their biological behavior in rats confirm certain differences. Tc-99m-Hipp is a renal agent clearing by the glomerular system, with better pharmacokinetical parameters than Tc-99m-DTPA: t(1/2(alpha)) = 4.1 min, t(1/2(beta)) = 198.6 min, K-d = 1.2.10(-2)min(-1) and a twofold value for blood clearance (Cl=2.07 ml/min). Tc-99m-PAH is a quite different renal agent, rapidly secreted by kidney as a tubular secretion agent. Its pharmacokinetical parameters: t(1/2(alpha)) = 2.5 min, t(1/2(beta)) = 41.7 min and K-cl = 5.1.10(-4) min(-1) are almost equal to those of Tc-99m-MAG(3), but the blood clearance of Cl = 5.22 ml/min is even higher than that of IOH clearance.

A modified Tc-99m(Sn)-pyrophosphate (PyP) kit for the application in nuclear cardiology (radioventriculography, angiocardiography, scintigraphy of blood pool) was developed. Each vial contains 12 mg PyP (Na4P2O7), 4 mg SnCl2. 2H(2)O, 2.5 mg gentisic acid and IO mg NaCl. The reconstitution is performed by dissolving the lyophilized kit in 3 mi 0.9% NaCl. In comparison with the standard pyrophosphate kit for bone scanning and detection of miocardial infarction, it contains an increased amount of Sn(Il) so that the molar ratio ligand/reductant is lowered from 25 to 2.5. The radiochemical analyses showed that the radiochemical purity of the labeled kit is high ( GT 90%) during three hours after addition of Tc-99m-activity. The shelf-life of the inactive freeze-dried preparation is up to four months providing that it is kept in vacuum and at appropriate temperature (2-8 degrees C). The biodistribution studies revealed increased accumulation in blood and low uptake by liver and kidneys. It was concluded that the modified kit performs stable and reproducible properties.

The complexation between tin(II) ion and glycine was studied in 0.15 mol/dm(3) NaCl medium at 310 K using potentiometric glass electrode titrations. In the pH range 1.1-4.5 and concentration range of the tin(II) between 0.2 and 5.0 mmol/dm(3), with variable glycine-to-tin molar ratio up to 10:1, the experimental data were explained by the formation of the following complexes and their overall stability constants: log(beta +/- sigma): Sn(HGly)(+), (12.78 +/- 0.08); Sn(Gly)(+), (10.02 +/- 0.07); Sn(OH)Gly, (7.34 +/- 0.03), as well as the pure hydrolytic complex Sn-4(OH)(6)(2+), whose stability constant was determined in separate experiments and found to be -4.30 +/- 0.08, under the same experimental conditions as for complexation study. The precipitate formed in tin(II)-glycine system at pH ca. 5.0 was characterized by chemical and TG analysis, I. R. spectra, X-ray powder diffraction, and electron scanning microscopy measurements. It has been shown that the precipitate has the composition Sn(OH)Gly and crystallizes in a tetragonal system with unit cell dimensions a = b = 1.584 nm, c = 0.597 nm. The mechanism of the complex formation in solution is discussed.