Polimery w medycynie最新文献

{"title":"[Applications of synthetic and semisynthetic polymers (Kollidon K25, Kollidon K90 and Hydroksyethylocellulose) as carriers of ketoprofen in solid oral prolonged release dosage forms. The impact of selected non-ionic surfactants (Tween 80 and Rofam 70) on the release kinetics].","authors":"W. Linka, M. Kołodziejczyk, Monika Monika Kamińska","doi":"10.17219/pim/109360","DOIUrl":"https://doi.org/10.17219/pim/109360","url":null,"abstract":"BACKGROUND Hydrophilic matrices used as oral forms of sustained release drugs are a suitable application medium for short-acting nonsteroidal anti-inflammatory drugs (NSAID) - ketoprofen. A properly selected hydrophilic matrix in oral preparations may significantly increase efficacy and application safety of ketoprofen. OBJECTIVES The aim of the research was to analyze the usefulness of polymers (synthetic Kollidon K25 and K90, semi-synthetic hydroxyethylcellulose) and calcium hydrogen phosphate dihydrate (as an inorganic filler) in manufacturing solid oral matrix forms of ketoprofen and to study of the effect of non-ionic surfactants (Tween 80, Rofam 70) on release kinetics. MATERIAL AND METHODS Ketoprofen, HEC, Kollidon K25, and K90, calcium hydrogen phosphate, magnesium stearate. Incorporation. Studies on the tablet mass. Direct tableting. Studies on the pharmacopoeial parameters and pharmaceutical availability. Approximation of the results. RESULTS The results of the granulometric studies on tablet mass were in accordance with pharmacopoeial standards. The results of morphological and biopharmaceutical studies of the obtained matrices (tablets) were consistent with the pharmacopoeial standards for formulations with HEC, K25 and K90. The release results most closely related to row 0 kinetics were obtained for the matrix containing HEC and K25. Tween 80 added to 0.1N HCl accelerated the release of ketoprofen, while Rofam 70 decelerated it. Tween 80 and Rofam 70 added to the pH 7.4 buffer accelerated the release of ketoprofen. CONCLUSIONS The presented model system of preformulation studies showed the usefulness of HEC and Kolidon K25 in the technology of hydrophilic matrices with ketoprofen. Surfactants added to the medium do not affect the release rate of ketoprofen.","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"22 1","pages":"5-18"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91208799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between compression pressure, mechanical strenghth and release properties of tablets.","authors":"O. Adeleye","doi":"10.17219/pim/111888","DOIUrl":"https://doi.org/10.17219/pim/111888","url":null,"abstract":"Tablets are a complex drug delivery system consisting of the active pharmaceutical ingredients and excipients. Tablet production involves a series of unit operations in which drugs and excipients are subjected to mechanical stresses, such as compression pressure, thus imposing changes in the properties of these materials. Variations in the compression pressure and other processing parameters may affect the mechanical strength and release properties of the final tablet. It is generally expected that an increase in compression pressure should lead to an increase in mechanical strength and a decrease in release properties of tablets, but this may not be true in some practical situation, since tablet production is the result of complex interaction between many factors involving the drug, excipient, the formulation, and processing variables. The degree and extent of interaction of these variables are not absolutely dependent on one factor. The aim of this review is to study the interaction between compression pressure, mechanical strength and release properties of immediate and controlled release tablets. The effect of compression pressure on tablets is complemented by such factors as the material properties of the drug and excipient, the formulation and processing factors, which in turn affects mechanical strength and release properties.","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"39 1","pages":"27-33"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86424417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of levodropropizine and hydroxypropyl-β-cyclodextrin association on the physicochemical characteristics of levodropropizine loaded in hydroxypropyl-β-cyclodextrin microcontainers: Formulation and in vitro characterization.","authors":"A. Yousaf, Alina Qadeer, S. Raza, T. Chohan, Y. Shahzad, F. Din, I. Khan, T. Hussain, M. Alvi, T. Mahmood","doi":"10.17219/pim/111887","DOIUrl":"https://doi.org/10.17219/pim/111887","url":null,"abstract":"BACKGROUND Poorly water-soluble drugs do not dissolve well in aqueous-based gastrointestinal fluid; therefore, they are not well absorbed. Thus, employing a suitable solubility enhancing technique is necessary for such a drug. Drug/HP‑β‑CD complexation is a promising way to improve solubility and dissolution of a poorly water-soluble drug. Levodropropizine was used as a model drug in this study. OBJECTIVES The purpose of this research was to enhance the aqueous solubility and dissolution rate of levodropropizine by employing the inclusion complexation technique. MATERIAL AND METHODS A microparticle formulation was prepared from levodropropizine and hydroxypropyl-β-cyclodextrin (HP‑β‑CD) in a 1:1 molar ratio through the spray-drying technique. The host-guest relationship between levodropropizine and HP‑β‑CD was also investigated using the molecular docking computational methodology. The aqueous solubility and dissolution rate of levodropropizine in formulations were assessed and compared with those of the drug alone. X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were applied for the solid-state characterization of the prepared samples. RESULTS According to the research outcomes, the levodropropizine/HP‑β‑CD formulation had enhanced the aqueous solubility (351.12 ±13.26 vs 92.76 ±5.00 mg/mL) and dissolution rate (97.83 ±3.36 vs 3.12 ±1.76% in 10 min) of levodropropizine, compared to the plain drug powder. The levodropropizine/ HP‑β‑CD formulation had converted the crystalline drug into its amorphous counterpart. Furthermore, no covalent interaction was found to exist between levodropropizine and HP‑β‑CD. The spray-dried particles were discrete. Each particle had a shriveled appearance. CONCLUSIONS The levodropropizine/HP‑β‑CD formulation is, therefore, recommended for the more effective administration of levodropropizine through the oral route.","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"75 1","pages":"35-43"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83842081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of sodium starch glycolate, croscarmellose sodium and crospovidone on disintegration and dissolution of stevia-loaded tablets.","authors":"A. Yousaf, Faiza Naheed, Y. Shahzad, T. Hussain, T. Mahmood","doi":"10.17219/pim/111516","DOIUrl":"https://doi.org/10.17219/pim/111516","url":null,"abstract":"BACKGROUND Sugar substitutes are used by diabetic, obese and calorie-conscious people. As artificial sweeteners are harmful to the body, natural sweeteners are more suitable. Sugar substitutes are available on the market in tablet forms, which are added to hot or cold drinks. Rapid disintegration and dissolution of sugar substitute-loaded tablet is desired. However, the tablets should be hard enough to maintain their integrity during mechanical shocks. OBJECTIVES The objective of this research was to develop rapidly disintegrating and dissolving stevia-loaded tablets with appropriate wetting, hardness and friability. MATERIAL AND METHODS Several tablets were prepared using different superdisintegrants using the direct compression method. Flowability tests of the powder blends were performed before compression; these test took into account such physical parameters as bulk density, tapped density, angle of repose, compressibility index, and Hausner's ratio. Evaluation of the compressed cores was accomplished with weight variation, hardness, thickness, friability, disintegration time, wetting time, and dissolution. RESULTS The disintegration time and wetting time of the tablets were in the following order: sodium starch glycolate > croscarmellose sodium > crospovidone containing tablets. A powder blend consisting of stevia extract, crospovidone, lactose, and magnesium stearate at the optimized ratio of 15/2.5/32/0.5 (w/w/w/w) showed the best flow, rapid disintegration (38 ±0.894 s), wetting (30 ±1 s), and dissolution (~ 95% in 1 min). Moreover, this formulation showed more rapid wetting (30 ±1 s vs 91 ±1.9 s), disintegration (38 ±0.894 s vs 143 ±1.276 s) and dissolution (~ 95% vs 60% in 1 min) than a commercial product. CONCLUSIONS The tablet consisting of stevia, crospovidone, lactose, and magnesium stearate at the weight ratio of 15/2.5/32/0.5 showed excellent results with regards to dissolution and disintegration; accordingly, this formulation could be a potential sugar substitute for diabetic, obese and/or calorie-conscious individuals.","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"93 1","pages":"19-26"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89084146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The preparation and physicochemical characterization of eprosartan mesylate-laden polymeric ternary solid dispersions for enhanced solubility and dissolution rate of the drug.","authors":"Abid Mehmood Yousaf,&nbsp;Sundas Zulfiqar,&nbsp;Yasser Shahzad,&nbsp;Talib Hussain,&nbsp;Tariq Mahmood,&nbsp;Muhammad Jamshaid","doi":"10.17219/pim/102976","DOIUrl":"https://doi.org/10.17219/pim/102976","url":null,"abstract":"<p><strong>Background: </strong>Eprosartan mesylate is a poorly water-soluble drug. It does not dissolve well in the aqueous gastrointestinal fluid, which means it is not absorbed well via the oral route, because a drug can cross cell membranes when it is dissolved in the gastrointestinal fluid.</p><p><strong>Objectives: </strong>The purpose of this research was to enhance the aqueous solubility and dissolution rate of eprosartan mesylate using the solid dispersion technique. Enhancing the solubility and dissolution leads to better absorption via the oral route.</p><p><strong>Material and methods: </strong>A number of eprosartan mesylate-laden polymeric solid dispersions were prepared with hydroxypropyl methylcellulose (HPMC) and polysorbate 80 by means of the solvent evaporation technique. The impact of the weight ratios of the constituents on the solubility and dissolution rate was studied in comparison with the plain drug. The formulation presenting the optimal solubility and dissolution underwent the solid-state characterization using X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR).</p><p><strong>Results: </strong>Both polysorbate 80 and HPMC positively affected the solubility and dissolution of eprosartan mesylate.</p><p><strong>Conclusions: </strong>In particular, a ternary solid dispersion consisting of eprosartan mesylate, HPMC and polysorbate 80 at a weight ratio of 1:4.2:0.3 showed the highest solubility (36.39 ± 3.95 mg/mL) and dissolution (86.19 ±4.09% in 10 min). Moreover, the drug was present in the amorphous form in the solid dispersion with no covalent drug-excipient interactions.</p>","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"48 2","pages":"69-75"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37093465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of media components and agricultural by-products on γ-polyglutamic acid production by Bacillus toyonensis As8.","authors":"Olubusola A Odeniyi,&nbsp;David S Avoseh","doi":"10.17219/pim/105555","DOIUrl":"https://doi.org/10.17219/pim/105555","url":null,"abstract":"<p><strong>Background: </strong>Poly-γ‑glutamic acid (γ‑PGA) provides an environmentally friendly alternative to plastic materials which have widely polluted the environment.</p><p><strong>Objectives: </strong>The microbial production of γ‑PGA, an amino acid biopolymer with glutamic acid subunits, was investigated using renewable agricultural residues in an attempt to find cheaper substitutes for conventional synthetic media components.</p><p><strong>Material and methods: </strong>Bacteria which produce γ‑PGA were isolated through depolymerizing Coix lacryma-jobi, a cellulosic grass, and the effects of various carbon and nitrogen sources, temperature, inoculant load, incubation period, and pH on γ‑PGA yield were determined after submerged fermentation. Bacterial growth was measured turbidimetrically at 550 nm. The γ‑PGA produced was characterized using Fourier transform infrared (FT-IR) spectroscopy and the polymer shape was determined using scanning electron microscopy (SEM).</p><p><strong>Results: </strong>The best γ‑PGA producer was molecularly identified as Bacillus toyonensis As8. The conditions which produced the highest γ‑PGA yield were glucose, ammonium sulfate, 25°C, a pH of 5.5, and an incubation period of 48 h. This bacterium yielded the most γ‑PGA (26.45 g/L) on cassava peels, while other agro-wastes (corn cob, sorghum leaves, Coix noir leaves, and rice bran) also supported bacterial growth with lower γ‑PGA yields than conventional carbon sources. The wrinkled γ‑PGA had absorbance peaks of hydroxyl, amide, carbonyl, and amine groups comparable with the ranges of those found in commercial γ‑PGA.</p><p><strong>Conclusions: </strong>The use of agricultural by-products as fermentation substrates increased γ‑PGA yield and may therefore be used as substitute components in γ‑PGA production.</p>","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"48 2","pages":"91-97"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37191629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the influence of cellulose derivatives on physical and analytical attributes of a drug product belonging to BCS class II.","authors":"Magdalena Domosławska,&nbsp;Renata Pawlak-Morka,&nbsp;Łukasz Dobrzyński,&nbsp;Monika Herda","doi":"10.17219/pim/104462","DOIUrl":"https://doi.org/10.17219/pim/104462","url":null,"abstract":"<p><strong>Background: </strong>Cellulose microcrystalline (MCC), hydroxypropyl methylcellulose (HPMC) and croscarmellose sodium are cellulose derivatives which are widely used in pharmaceutical technology. Although they are inert pharmaceutical ingredients, they can influence the release profile of an active substance from the dosage form depending on their distribution, type and quantity used in the formulation.</p><p><strong>Objectives: </strong>The aim of the present investigation was to examine the effect of chosen cellulose derivatives on the physical and analytical attributes of a drug product containing an active substance of Biopharmaceutics Classification System (BCS) class II.</p><p><strong>Material and methods: </strong>The tablets were prepared using the wet granulation technology. The batches differed in the amount and grade of HPMC, the type of MCC and the distribution of croscarmellose sodium. The granule properties as well as physical (tablet hardness, disintegration time, friability) and analytical (dissolution profile in different media) attributes of the tablets were examined.</p><p><strong>Results: </strong>The flow characteristics were satisfying in the case of all prepared batches. However, the differences in flow properties were visible, especially in the cases where MCC of coarser particles was replaced with MCC of finer particles. The type of MCC used in the product formula also had a significant influence on the drug product dissolution profile. The batches in which MCC of finer particles was used had substantially better results, regardless of HPMC viscosity type and the distribution of croscarmellose sodium between the inner and outer phase. What is more, the differences in the results between batches of different MCC types were especially visible in dissolution conditions, i.e., 0.1N hydrochloric acid (HCl).</p><p><strong>Conclusions: </strong>By choosing the right type, quantity and distribution of cellulose derivatives, it was possible to obtain the optimal formula of the drug product similar to in-vitro conditions to the reference drug. Out of all the tested excipients, the type of cellulose microcrystalline was found to have the most critical influence on both physical and analytical properties of the pharmaceutical formulation.</p>","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"48 2","pages":"83-90"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37263486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The polymorphism of statins and its effect on their physicochemical properties.","authors":"Marta Karaźniewicz-Łada,&nbsp;Karina Bąba,&nbsp;Filip Dolatowski,&nbsp;Alicja Dobrowolska,&nbsp;Marlena Rakicka","doi":"10.17219/pim/102978","DOIUrl":"https://doi.org/10.17219/pim/102978","url":null,"abstract":"<p><p>Polymorphism of pharmaceutical substances has a significant impact on their physicochemical properties, durability, bioavailability and consequently on their pharmacological activity. Solid dosage forms may exist in both crystalline and amorphous forms. Amorphous varieties are characterized by higher solubility and dissolution rates, while crystalline forms show greater purity and storage stability. The choice between the crystalline or amorphous form of a drug is extremely important to ensure effective and safe pharmacotherapy. Statins - the most commonly used group of drugs in the treatment of lipid disorders - are an example of drugs that occur in many crystalline and amorphous forms. Statins belong to class II in the biopharmaceutical classification system (BCS), which means that they are poorly soluble, but permeate biological membranes well. The bioavailability of statins shows considerable variation, which is associated with the first-pass effect in the liver and the accumulation of the drug in the hepatocytes. The improvement of bioavailability after oral administration of poorly soluble medicinal substances remains one of the most challenging aspects of the drug development process. A specific polymorphic form is obtained by applying appropriate conditions during the process of its preparation under industrial conditions, including the use of a suitable solvent, a specific temperature or rate of crystallization. The article provides a comprehensive update on the current knowledge of the influence of polymorphic form on statin solubility and bioavailability. Research is still being carried out to obtain new polymorphic varieties of statins that are characterized by better physicochemical and pharmacokinetic parameters.</p>","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"48 2","pages":"77-82"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37094876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formulation and solid state characterization of carboxylic acid-based co-crystals of tinidazole: An approach to enhance solubility.","authors":"Jyotsana R Madan,&nbsp;Rishikesh H Dagade,&nbsp;Rajendra Awasthi,&nbsp;Kamal Dua","doi":"10.17219/pim/105609","DOIUrl":"https://doi.org/10.17219/pim/105609","url":null,"abstract":"<p><strong>Background: </strong>Tinidazole (TNZ) is an anti-parasite drug used in the treatment of a variety of amebic and parasitic infections. It has low solubility in aqueous media and is categorized under Class II of the Biopharmaceutical Classification System.</p><p><strong>Objectives: </strong>The aim of this research was to study the potential for enhancing the solubility of TNZ using carboxylic acid co-crystals.</p><p><strong>Material and methods: </strong>The solubility of TNZ was determined individually using 6 carboxylic acids for forming co-crystals at a 1:1 stoichiometric ratio. Three carboxylic acids - namely tartaric acid (TA), oxalic acid (OA) and glutaric acid (GA) - resulted in the formation of co-crystals with enhanced solubility. An equilibrium solubility study of TNZ co-crystals at 1:1.5 and 1:2 stoichiometric ratios was also carried out. The co-crystals which developed were evaluated using X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC) to study the drug-co-crystal former interactions.</p><p><strong>Results: </strong>The solubility of TNZ in distilled water was found to be 0.014 mg/mL. The highest enhancement ratio was obtained with TNZ and TA at a ratio of 1:1. Differential scanning calorimetry thermograms suggested that the drug and carboxylic acids had undergone interactions such as hydrogen bonding. The XRD and DSC results confirmed the formation of co-crystals.</p><p><strong>Conclusions: </strong>It was concluded that the results of enhanced solubility of TNZ using co-crystals is a clear indication of the potential for co-crystals to be used in the future for other poorly water-soluble drugs, considering that co-crystals are a safe and cost-effective approach.</p>","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"48 2","pages":"99-104"},"PeriodicalIF":0.0,"publicationDate":"2018-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37192965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Study of the structure of contact lenses using PALS, MIR and Raman spectroscopy in the regard of safety of persons exposed to ionizing radiation].","authors":"Mariusz Budaj,&nbsp;Andrzej Michalski,&nbsp;Bogdan Miśkowiak,&nbsp;Katarzyna Filipecka,&nbsp;Sylwia Mandecka","doi":"10.17219/pim/96287","DOIUrl":"https://doi.org/10.17219/pim/96287","url":null,"abstract":"<p><p>Among patients and health professionals who are exposed to ionizing radiation during diagnostic and therapeutic procedures, refractive errors are common and soft contact lenses are widely used to correct them. Changes in the inner structure of contact lens may influence the safety of its usage through modification of its water content or oxygen accessibility to cornea. Therefore, analysis of impact of external factors, therein ionizing radiation used in medicine, on contact lenses parameters is necessary, particularly to compare the presence of free volume gaps in the structure of the polymer soft contact lenses. Possible change in dimensions or quantity of free volume gaps in the structure of the material caused by the exposure to ionizing radiation may have negative influence on oxygen permeability. To prevent such process, different means could be used, i.a., positron annihilation lifetime spectroscopy (PALS), Raman spectroscopy and mid-infrared spectroscopy (MIR). Use of contact lenses which reduce transport of oxygen to cornea increases the risk of corneal hypoxia - one of the possible complications of using contact lenses. Research on effects of different types of ionizing radiation (X-ray, gamma, beta) on materials used in production of contact lenses is vital because of the connection of this issue with the safety of contact lenses wearers. Such research can also shed light on the problem of safe use of contact lenses by persons exposed to ionizing radiation.</p>","PeriodicalId":20355,"journal":{"name":"Polimery w medycynie","volume":"48 1","pages":"5-9"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36723626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}