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Bonilla DA, Kreider RB, Stout JR, Forero DA, Kerksick CM, Roberts MD, Rawson ES. Metabolic Basis of Creatine in Health and Disease: A Bioinformatics-Assisted Review. Nutrients 2021; 13:nu13041238. [PMID: 33918657 PMCID: PMC8070484 DOI: 10.3390/nu13041238] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/01/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023] Open
Abstract
Creatine (Cr) is a ubiquitous molecule that is synthesized mainly in the liver, kidneys, and pancreas. Most of the Cr pool is found in tissues with high-energy demands. Cr enters target cells through a specific symporter called Na+/Cl−-dependent Cr transporter (CRT). Once within cells, creatine kinase (CK) catalyzes the reversible transphosphorylation reaction between [Mg2+:ATP4−]2− and Cr to produce phosphocreatine (PCr) and [Mg2+:ADP3−]−. We aimed to perform a comprehensive and bioinformatics-assisted review of the most recent research findings regarding Cr metabolism. Specifically, several public databases, repositories, and bioinformatics tools were utilized for this endeavor. Topics of biological complexity ranging from structural biology to cellular dynamics were addressed herein. In this sense, we sought to address certain pre-specified questions including: (i) What happens when creatine is transported into cells? (ii) How is the CK/PCr system involved in cellular bioenergetics? (iii) How is the CK/PCr system compartmentalized throughout the cell? (iv) What is the role of creatine amongst different tissues? and (v) What is the basis of creatine transport? Under the cellular allostasis paradigm, the CK/PCr system is physiologically essential for life (cell survival, growth, proliferation, differentiation, and migration/motility) by providing an evolutionary advantage for rapid, local, and temporal support of energy- and mechanical-dependent processes. Thus, we suggest the CK/PCr system acts as a dynamic biosensor based on chemo-mechanical energy transduction, which might explain why dysregulation in Cr metabolism contributes to a wide range of diseases besides the mitigating effect that Cr supplementation may have in some of these disease states.
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Affiliation(s)
- Diego A. Bonilla
- Research Division, Dynamical Business & Science Society–DBSS International SAS, Bogotá 110861, Colombia
- Research Group in Biochemistry and Molecular Biology, Universidad Distrital Francisco José de Caldas, Bogotá 110311, Colombia
- Research Group in Physical Activity, Sports and Health Sciences (GICAFS), Universidad de Córdoba, Montería 230002, Colombia
- kDNA Genomics, Joxe Mari Korta Research Center, University of the Basque Country UPV/EHU, 20018 Donostia-San Sebastián, Spain
- Correspondence: ; Tel.: +57-320-335-2050
| | - Richard B. Kreider
- Exercise & Sport Nutrition Laboratory, Human Clinical Research Facility, Texas A&M University, College Station, TX 77843, USA;
| | - Jeffrey R. Stout
- Physiology of Work and Exercise Response (POWER) Laboratory, Institute of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL 32816, USA;
| | - Diego A. Forero
- Professional Program in Sport Training, School of Health and Sport Sciences, Fundación Universitaria del Área Andina, Bogotá 111221, Colombia;
| | - Chad M. Kerksick
- Exercise and Performance Nutrition Laboratory, School of Health Sciences, Lindenwood University, Saint Charles, MO 63301, USA;
| | - Michael D. Roberts
- School of Kinesiology, Auburn University, Auburn, AL 36849, USA;
- Edward via College of Osteopathic Medicine, Auburn, AL 36849, USA
| | - Eric S. Rawson
- Department of Health, Nutrition and Exercise Science, Messiah University, Mechanicsburg, PA 17055, USA;
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van der Poel AFB, Braun U, Hendriks WH, Bosch G. Stability of creatine monohydrate and guanidinoacetic acid during manufacture (retorting and extrusion) and storage of dog foods. J Anim Physiol Anim Nutr (Berl) 2019; 103:1242-1250. [PMID: 31074123 PMCID: PMC6852548 DOI: 10.1111/jpn.13103] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 12/10/2018] [Accepted: 03/26/2019] [Indexed: 12/23/2022]
Abstract
The stability of creatine monohydrate (CrMH), crystallised guanidinoacetic acid (GAA-C) and granulated GAA (GAA-G) in a moist retorted and a dry extruded dog food formulation during production and storage was investigated. Commercial food mixtures were supplemented with CrMH, GAA-C or GAA-G. Uniformity after mixing and retorting or extrusion was determined based on replicate samples (moist n = 8, dry n = 10). Storage stability was evaluated at 25°C/60% relative humidity for 15 months and 40°C/75% for 6 months. Foods with CrMH were analysed for creatine (Cr) and creatinine (Crn), whereas GAA-C and GAA-G foods were analysed for GAA concentrations. Coefficients of variation (CV) for uniformity of the additives after mixing of moist and dry pet food formulations were below 15%, and the CV was lower in processed mixtures. Recoveries after retorting and extrusion were higher for GAA-G (79 and 99%) and GAA-C (89 and 86%) compared to CrMH (36 and 85%) foods. In moist CrMH food, Cr concentrations re-increased by 54% whilst Crn concentrations decreased by 39% after storage at 25°C for 15 months. With total molar Cr + Crn remaining stable throughout storage, Crn and Cr appeared to effectively interconvert. Storage of the extruded CrMH food at 25°C for 15 months resulted in a 63% decrease in Cr and a 39% increase in Crn concentration. The decrease in Cr concentration was larger at 6 months storage at 40°C compared to 15 months storage at 25°C. Both GAA-C and GAA-G moist and dry foods were stable during storage (<10% decrease). This study showed that GAA is highly stable during production and storage of moist and dry canine foods whilst CrMH is relatively unstable, particularly during storage. The latter makes it difficult to establish a guaranteed Cr content in finished moist retorted and dry extruded foods with CrMH.
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Affiliation(s)
- Antonius F B van der Poel
- Animal Nutrition group, Department of Animal Sciences, Wageningen University & Research, Wageningen, The Netherlands
| | | | - Wouter H Hendriks
- Animal Nutrition group, Department of Animal Sciences, Wageningen University & Research, Wageningen, The Netherlands.,Department of Farm Animal Health, Utrecht University, Utrecht, The Netherlands
| | - Guido Bosch
- Animal Nutrition group, Department of Animal Sciences, Wageningen University & Research, Wageningen, The Netherlands
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Vraneš M, Ostojić S, Tot A, Papović S, Gadžurić S. Experimental and computational study of guanidinoacetic acid self-aggregation in aqueous solution. Food Chem 2017; 237:53-57. [PMID: 28764030 DOI: 10.1016/j.foodchem.2017.05.088] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 04/21/2017] [Accepted: 05/17/2017] [Indexed: 10/19/2022]
Abstract
In this work for the first time the physicochemical and thermal properties of guanidinoacetic acid (GAA) and its aqueous solutions have been performed to test for its viability as a potential dietary supplement. Thermal stability, viscosity, solubility and experimental density are determined. From measured densities the volumetric properties were estimated and discussed in the scope of GAA self-aggregation in aqueous solutions using experimental and computational results. Based on thermal stability and solubility measurements, it is found that GAA is more thermally stable but less soluble comparing to creatine due to a self-aggregation process that occurs at GAA concentrations higher than 0.013mol·dm-3. Existence of self-aggregation influences the macroscopic properties of aqueous GAA solutions, but also its bioavailability.
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Affiliation(s)
- Milan Vraneš
- Faculty of Science, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia.
| | - Sergej Ostojić
- Faculty of Sport and Physical Education, University of Novi Sad, Lovćenska 16, 21000 Novi Sad, Serbia.
| | - Aleksandar Tot
- Faculty of Science, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia.
| | - Snežana Papović
- Faculty of Science, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia.
| | - Slobodan Gadžurić
- Faculty of Science, Department of Chemistry, Biochemistry and Environmental Protection, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia.
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Gangopadhyay D, Sharma P, Singh RK. Temperature dependent Raman and DFT study of creatine. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 150:9-14. [PMID: 26010702 DOI: 10.1016/j.saa.2015.05.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Revised: 04/22/2015] [Accepted: 05/04/2015] [Indexed: 06/04/2023]
Abstract
Temperature dependent Raman spectra of creatine powder have been recorded in the temperature range 420-100K at regular intervals and different clusters of creatine have been optimized using density functional theory (DFT) in order to determine the effect of temperature on the hydrogen bonded network in the crystal structure of creatine. Vibrational assignments of all the 48 normal modes of the zwitterionic form of creatine have been done in terms of potential energy distribution obtained from DFT calculations. Precise analysis gives information about thermal motion and intermolecular interactions with respect to temperature in the crystal lattice. Formation of higher hydrogen bonded aggregates on cooling can be visualized from the spectra through clear signature of phase transition between 200K and 180K.
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Affiliation(s)
| | - Poornima Sharma
- Department of Physics, Banaras Hindu University, Varanasi 221005, India
| | - Ranjan K Singh
- Department of Physics, Banaras Hindu University, Varanasi 221005, India.
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Braun DE, Orlova M, Griesser U. Creatine: Polymorphs Predicted and Found. CRYSTAL GROWTH & DESIGN 2014; 14:4895-4900. [PMID: 26722225 PMCID: PMC4693963 DOI: 10.1021/cg501159c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Hydrate and anhydrate crystal structure prediction (CSP) of creatine (CTN), a heavily used, badly water soluble, zwitterionic compound, has enabled the finding and characterization of its anhydrate polymorphs, including the thermodynamic room temperature form. Crystal structures of the novel forms were determined by combining laboratory powder X-ray diffraction data and ab initio generated structures. The computational method not only revealed all experimental forms but predicted the correct stability order, which was experimentally confirmed by measurements of the heat of hydration.
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Affiliation(s)
- Doris E. Braun
- Institute of Pharmacy and Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria
- Tel: +43(0)512 507 58653; E-mail:
| | - Maria Orlova
- Institute of Pharmacy and Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria
| | - Ulrich
J. Griesser
- Institute of Pharmacy and Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria
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Arlin JB, Bhardwaj RM, Johnston A, Miller GJ, Bardin J, MacDougall F, Fernandes P, Shankland K, David WIF, Florence AJ. Structure and stability of two polymorphs of creatine and its monohydrate. CrystEngComm 2014. [DOI: 10.1039/c4ce00508b] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gao J, Hu Y, Li S, Zhang Y, Chen X. Tautomeric equilibrium of creatinine and creatininium cation in aqueous solutions explored by Raman spectroscopy and density functional theory calculations. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2012.11.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Gufford BT, Sriraghavan K, Miller NJ, Miller DW, Gu X, Vennerstrom JL, Robinson DH. Physicochemical characterization of creatine N-methylguanidinium salts. J Diet Suppl 2012; 7:240-52. [PMID: 22432515 DOI: 10.3109/19390211.2010.491507] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Creatine is widely used as a dietary supplement for body builders to enhance athletic performance. As the monohydrate, its low solubility in water and high dose lead to water retention and gastrointestinal discomfort. Hence, alternative creatine derivatives with enhanced water solubility and potential therapeutic advantages have been synthesized. As a zwitterionic compound, creatine can form salts at the N-methyl guanidinium or carboxylic acid functional groups. In this study, we determined the aqueous solubilities and partition coefficients of six N-methyl guanidinium salts of creatine compared to those of creatine monohydrate; two of these were new salts, namely, creatine mesylate and creatine hydrogen maleate. The aqueous solubilities of the salts were significantly more than that of creatine monohydrate with the hydrochloride and mesylate being 38 and 30 times more soluble, respectively. The partition coefficients of the creatine salts were very low indicating their relatively high polarity. Permeabilities of creatine pyruvate, citrate, and hydrochloride in Caco-2 monolayers were compared to that of creatine monohydrate. Aside from the creatine citrate salt form that had reduced permeability, there were no significant differences in permeability characteristics in Caco-2 monolayers. Typical of an amphoteric compound, creatine is least soluble in the pH region near the isoelectric point.
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Affiliation(s)
- Brandon T Gufford
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, Nebraska, USA
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Jäger R, Purpura M, Shao A, Inoue T, Kreider RB. Analysis of the efficacy, safety, and regulatory status of novel forms of creatine. Amino Acids 2011; 40:1369-83. [PMID: 21424716 PMCID: PMC3080578 DOI: 10.1007/s00726-011-0874-6] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Accepted: 11/30/2010] [Indexed: 11/28/2022]
Abstract
Creatine has become one of the most popular dietary supplements in the sports nutrition market. The form of creatine that has been most extensively studied and commonly used in dietary supplements is creatine monohydrate (CM). Studies have consistently indicated that CM supplementation increases muscle creatine and phosphocreatine concentrations by approximately 15–40%, enhances anaerobic exercise capacity, and increases training volume leading to greater gains in strength, power, and muscle mass. A number of potential therapeutic benefits have also been suggested in various clinical populations. Studies have indicated that CM is not degraded during normal digestion and that nearly 99% of orally ingested CM is either taken up by muscle or excreted in urine. Further, no medically significant side effects have been reported in literature. Nevertheless, supplement manufacturers have continually introduced newer forms of creatine into the marketplace. These newer forms have been purported to have better physical and chemical properties, bioavailability, efficacy, and/or safety profiles than CM. However, there is little to no evidence that any of the newer forms of creatine are more effective and/or safer than CM whether ingested alone and/or in combination with other nutrients. In addition, whereas the safety, efficacy, and regulatory status of CM is clearly defined in almost all global markets; the safety, efficacy, and regulatory status of other forms of creatine present in today’s marketplace as a dietary or food supplement is less clear.
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Affiliation(s)
- Ralf Jäger
- Increnovo LLC, 2138 E Lafayette Pl., Milwaukee, WI 53202, USA
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Singh S, Dash AK. Chapter 1 creatine monohydrate. PROFILES OF DRUG SUBSTANCES, EXCIPIENTS, AND RELATED METHODOLOGY 2009; 34:1-35. [PMID: 22469171 DOI: 10.1016/s1871-5125(09)34001-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Sakata Y, Shiraishi S, Otsuka M. Effect of pulverization of the bulk powder on the hydration of creatine anhydrate tablets and their pharmaceutical properties. Colloids Surf B Biointerfaces 2005; 46:92-100. [PMID: 16274970 DOI: 10.1016/j.colsurfb.2005.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2005] [Revised: 09/08/2005] [Accepted: 10/04/2005] [Indexed: 11/25/2022]
Abstract
The hydration behavior and expansion properties of untreated and pulverized creatine anhydrate (CRA) tablets were studied under 60 and 75%RH at 25 degrees C by using differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD). The tablet hardness of untreated and pulverized CRA tablets was significantly decreased after hydration. There was a linear relationship between the degree of hydration and the tablet hardness of untreated CRA tablets compressed at 1000 kg/cm2. In contrast, the relationship between the degree of hydration and the tablet hardness of pulverized CRA tablets was nonlinear. These results suggest that the reduction in hardness of pulverized CRA tablets does not depend solely on the hydration level of crystal water. PXRD analysis indicated that the diffraction pattern of the pulverized CRA powder was similar to that of the untreated CRA powder. However, the diffraction intensity of the pulverized CRA powder was slightly lower than that of the untreated CRA powder at high angle. The micropore radius of both untreated and pulverized CRA tablets was significantly increased after hydration, but analysis of the relationship between micropore radius and fractional hydration of crystal water showed that untreated CRA tablets were more affected than pulverized CRA tablets. Therefore, the reduction in tablet hardness depends not only on the hydration behavior but also on the crystal orientation of the CRA powder.
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Affiliation(s)
- Yukoh Sakata
- Healthcare Research Institute, Wakunaga Pharmaceutical Co., Ltd., 1624 Shimokotachi, Kodacho, Takatagun, Hiroshima 739-1195, Japan.
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Sakata Y, Shiraishi S, Otsuka M. Effect of pulverization on hydration kinetic behaviors of creatine anhydrate powders. Colloids Surf B Biointerfaces 2004; 39:187-93. [PMID: 15555902 DOI: 10.1016/j.colsurfb.2004.07.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2004] [Accepted: 07/28/2004] [Indexed: 11/26/2022]
Abstract
The crystal orientation of creatine monohydrate varies significantly with tableting performance and pulverizing mechanism. Furthermore, the X-ray diffraction patterns of anhydrous forms of untreated creatine monohydrate and of pulverized creatine monohydrate exhibit different crystal orientations. However, hygroscopic forms of unpulverized creatine anhydrate and pulverized creatine anhydrate was exhibit the same diffraction peak pattern. The hygroscopicity of unpulverized and pulverized creatine anhydrate has been investigated by hydration kinetic methods using isothermal differential scanning calorimetry data. Testing of the hygroscopicity of unpulverized and pulverized creatine anhydrate at various levels of relative humidity (RH) at 25 degrees C revealed that the anhydrate was stable at less than 33% RH, but was transformed into the monohydrate at more than 52% RH. Hydration data of unpulverized and pulverized creatine anhydrate at 60% and 75% RH were calculated to determine hydration kinetics using various solid-state kinetic models. The hydration type of unpulverized and pulverized creatine anhydrate powder follows the zero-order mechanism (Polany-Winger equation) R1. The transition rate constant of pulverized creatine anhydrate, calculated from the slope of the straight line, was about 1.34-1.36 times higher than that of unpulverized creatine anhydrate.
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Affiliation(s)
- Yukoh Sakata
- Healthcare Research Institute, Wakunaga Pharmaceutical Co. Ltd., 1624 Shimokotachi, Kodacho, Takatagun, Hiroshima 739-1195, Japan.
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Marini A, Berbenni V, Bruni G, Cofrancesco P, Margheritis C, Orlandi A, Villa M. Hydration, stability, and phase transformations of a new antitumor drug. J Pharm Sci 2004; 93:2222-31. [PMID: 15295783 DOI: 10.1002/jps.20128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We studied hydration equilibria and phase transformations in a cytotoxic drug (BBR3576). The original sample is a hydrated compound that undergoes a structural phase transition when it looses about half of its structural water. Such a structural transition is completely reversible: the partially dehydrated form is stable up to 130 degrees C (or up to 140 degrees C for several minutes) and reverts to the original form upon rehydration. Completely different phase relationships are observed if an original sample is fully dehydrated: when all water has been released, a metastable anhydrous phase forms, which undergoes an irreversible exothermic conversion to a stable phase. Upon rehydration at room temperature of such an anhydrous phase, a new hydrated form is obtained, which is definitely different from the original one.
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Affiliation(s)
- A Marini
- C.S.G.I., Dipartimento di Chimica Fisica dell'Università degli Studi di Pavia, Via Taramelli 16, 27100 Pavia, Italy.
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Persky AM, Hochhaus G, Brazeau GA. Validation of a simple liquid chromatography assay for creatine suitable for pharmacokinetic applications, determination of plasma protein binding and verification of percent labeled claim of various creatine products. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 794:157-65. [PMID: 12888208 DOI: 10.1016/s1570-0232(03)00452-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Creatine has been quantified in various tissues by a range of methodologies. This paper reports on the development and validation of a simplified HPLC assay to determine plasma creatine, plasma protein binding of creatine, creatine in microdialysate and creatine in over-the-counter products. An isocratic, reversed-phase (C(18)) HPLC assay, using potassium phosphate monobasic (pH 4) as a mobile phase, was validated in human plasma and microdialysis perfusion fluid (normal saline). The lower limit of quantification for the assay was 1 mg l(-1) in saline and 5 mg l(-1) in plasma. The RSD was below 6% and accuracy was below 12% in both matrices. Protein binding in human plasma was found to be negligible (<10%). Over-the-counter creatine monohydrate products tested contained 100% creatine monohydrate. This assay was found to be suitable for pharmacokinetic studies and the assessment of plasma creatine and skeletal muscle microdialysate.
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Affiliation(s)
- Adam M Persky
- Department of Pharmaceutics, University of Florida, College of Pharmacy, Gainesville, FL 32610, USA.
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Ganguly S, Jayappa S, Dash AK. Evaluation of the stability of creatine in solution prepared from effervescent creatine formulations. AAPS PharmSciTech 2003; 4:E25. [PMID: 12916907 PMCID: PMC2750587 DOI: 10.1208/pt040225] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The objectives of this study were to determine the cause of the crystallization in a large volume creatine supplement solution made from effervescent powders containing di-creatine citrate, and to characterize these crystals using thermal analyses and x-ray diffractometry. Creatine effervescent powders were dissolved in deionized water (pH 6.2) and stored both at room temperature (RT) (25 degrees C) and refrigerated condition (4 degrees C) over a period of 45 days. Creatine concentration was determined using high-performance liquid chromatography (HPLC). Intrinsic dissolution and saturated solubility of creatine, creatine monohydrate, and di-creatine citrate in water were determined and compared. Crystal growth was detected only in the refrigerated samples on the seventh day of storage. Differential Scanning Calorimetry (DSC) and x-ray diffraction (XRD) studies revealed that the crystals formed were of creatine monohydrate. Ninety percent creatine degradation was observed within 45 days for RT samples. However, at refrigerated condition this degradation was 80% within the same time period. The pH of the RT samples also increased from 3.6 to 4.5 during storage. No such increase was observed in the case of refrigerated samples. The intrinsic dissolution rate constants of the compounds decreased in the following order: di-creatine citrate > creatine > creatine monohydrate. In conclusion, di-creatine citrate used in effervescent formulation dissociates to creatine in aqueous solution and eventually crystallizes out as creatine monohydrate. Significant decrease in solubility and effect of pH contribute to this crystallization process.
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Affiliation(s)
- Sudipta Ganguly
- Department of Pharmacy Sciences, School of Pharmacy and Heath Professions, Creighton University Medical Center, 2500 California Plaza, 68178 Omaha, NE
| | - Sheela Jayappa
- Department of Pharmacy Sciences, School of Pharmacy and Heath Professions, Creighton University Medical Center, 2500 California Plaza, 68178 Omaha, NE
| | - Alekha K. Dash
- Department of Pharmacy Sciences, School of Pharmacy and Heath Professions, Creighton University Medical Center, 2500 California Plaza, 68178 Omaha, NE
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