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1.
Heliyon ; 10(7): e28314, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38571604

ABSTRACT

Maize tortilla is the best-recognized food product of Mexican gastronomy. Artisanal maize tortillas (AMT) are prepared with native maize varieties and a traditional process. The aims of this study were to identify sensory attributes, texture, and color in AMT that allow them to be differentiated from commercial tortillas, and to determine the chemical and mineral composition of both types of tortillas. Six landraces related to four Mexican maize races were used. Two commercial tortillas were included as references (tortillería and supermarket). Tortillas were subjected to sensory analysis by the modified Flash technique, texture and color were measured objectively and chemical and mineral analysis of all tortillas were evaluated. Lime taste and lime smell attributes were relevant to differentiate AMT from commercial tortillas; aftertaste and fracturability attributes were highly associated to supermarket tortillas. The fracturability attribute of tortillas is consider undesirable for taco preparation. Five of the six AMT were characterized by the presence of a layer, a characteristic that is associated with traditional tortilla made by Mexican consumer. Regarding chemical composition, supermarket tortillas exhibited the highest dietary fiber content (17.09%), but showed 30% more Na than AMT, with the exception of tortillas from Purepecha native variety. Besides, supermarket tortilla had 48.9% less Ca than AMT. The sensory attributes relevant to differentiate native maize tortillas from the commercial maize tortilla references were appearance, smell, and taste, while textural and color attributes played a lesser role.

2.
Rev. méd. Chile ; 150(12): 1619-1624, dic. 2022. ilus, tab
Article in Spanish | LILACS | ID: biblio-1515392

ABSTRACT

BACKGROUND: In those patients who do not have timely access to primary angioplasty, the pharmaco-invasive approach, that is, the use of thrombolysis as a bridging measure prior to the coronary angiography, is a safe alternative. AIM: To describe the features of patients with an acute ST-elevation myocardial infarction (STEMI) treated with a pharmaco-invasive strategy. MATERIAL AND METHODS: Descriptive observational study of 144 patients with mean age of 46 years with STEMI who received a dose of thrombolytic prior to their referral for primary angioplasty at a public hospital between 2018 and 2021. RESULTS: There were no differences the clinical presentation according to the Killip score at admission between thrombolyzed and non-thrombolyzed patients (p = ns). Fifty-three percent of non-thrombolyzed patients were admitted with an occluded vessel (TIMI 0) compared with 27% of thrombolyzed patients (p < 0.001). The thrombolyzed group required significantly less use of thromboaspiration (3.5 and 8.4% respectively; p = 0.014). Despite this, 91 and 92% of non-thrombolyzed and thrombolyzed patients achieved a post-angioplasty TIMI 3 flow. Long-term survival was 91 and 86% in thrombolyzed and non-thrombolyzed patients, respectively (p = ns). CONCLUSIONS: The pharmaco-invasive strategy is a safe alternative when compared to primary angioplasty in centers that don't have timely access to Interventional Cardiology.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , ST Elevation Myocardial Infarction/drug therapy , Survival Analysis , Thrombolytic Therapy , Treatment Outcome , Coronary Angiography , Fibrinolytic Agents/therapeutic use , Myocardial Infarction/drug therapy
3.
Andes Pediatr ; 93(2): 265-269, 2022 Apr.
Article in Spanish | MEDLINE | ID: mdl-35735307

ABSTRACT

Cystic lymphatic malformation (CLM) is a rare and benign entity caused by alterations in the embryological development of lymphatic structures. Its typical location is in the head and neck, although it has also been described at the abdominal level. It may not be evident in the first stages of life and its first manifestation may be a complication such as abdominal distension, hemorrhage, or sepsis, which may put the patient's life at risk. Surgical treatment is increasingly discussed, and less invasive techniques are proposed. OBJECTIVE: To describe an uncommon presentation of CLM, radiographic findings, complications, differential diagnosis, and both invasive and more conservative treatments. CLINICAL CASE: Newborn female infant consulted for fever and irritability, without specific signs on physical examination, with suspicion of sepsis. Ultrasonography showed a complex septate mass with cysts of different sizes encompassing the mesenteric vessels, supravesical location. In its most ante rior aspect, it presented a greater echogenicity that corresponded to the superinfected component. Magnetic resonance imaging identified a multitabulated cystic tumor corresponding to a complica ted mesenteric lymphangioma with signs of infection. Due to its size, which compressed the vena cava and the associated signs of complication, complete resection was decided with good subsequent evolution. CONCLUSION: The treatment of CLM in pediatric age is increasingly individualized and can vary from surgical resection to less invasive approaches that could reduce acute intraoperative or postoperative complications and mortality. In our case, the infection acted as sclerotherapy, mana ging to delimit the CLM and helping to improve the prognosis.


Subject(s)
Lymphangioma, Cystic , Lymphatic Abnormalities , Neonatal Sepsis , Child , Citrobacter freundii , Female , Humans , Infant , Infant, Newborn , Lymphangioma, Cystic/diagnostic imaging , Lymphangioma, Cystic/surgery , Lymphatic Abnormalities/pathology , Mesentery/pathology , Neonatal Sepsis/pathology
4.
Rev. otorrinolaringol. cir. cabeza cuello ; 82(2): 179-183, jun. 2022. ilus
Article in Spanish | LILACS | ID: biblio-1389852

ABSTRACT

Resumen La patología del sistema nervioso central, habitualmente, no provoca síntomas auditivos unilaterales, ya que la vía auditiva central está formada por una red de conexiones cruzadas entre los diferentes núcleos que la forman. Además, hay que considerar que una lesión pequeña puede extenderse a más de una estructura provocando varios déficits neurológicos debido a la proximidad de los tractos y núcleos nerviosos. Las lesiones unilaterales circunscritas en el colículo inferior son infrecuentes. No obstante, se han descrito casos en los que lesiones unilaterales de diversas etiologías en esta localización causaban síntomas auditivos. Ya que la vía auditiva central es cruzada, síntomas auditivos detectados con más frecuencia afectaban concretamente a la capacidad de localización del sonido o la comprensión verbal. Presentamos el caso de un hombre de 44 años con acúfeno unilateral derecho de larga evolución, sin otra clínica asociada quien fue diagnosticado de un tumor en el colículo inferior derecho mediante resonancia magnética cerebral. Se exponen los hallazgos clínicos y radiológicos del caso.


Abstract Central nervous system diseases usually do not cause auditory symptoms because the central auditory pathway consists on a network of crossed connections between the different nuclei that form it. In addition, we must consider that a small lesion might extend to more than one structure producing many neurologic symptoms due to the proximity of tracts and nuclei in the midbrain. Unilateral circumscribed lesions at inferior colliculus are rare. Nevertheless, lesions at this location causing auditory symptoms have been described. Because of the crossed central auditory pathway, the most commonly detected auditory symptoms specifically affected the ability to locate sound or verbal comprehension. We present the case of a 44-year-old man with a long-term monoaural right-sided tinnitus without other complaints who was diagnosed of a tumour at right inferior colliculus by neuroimaging. Clinical and radiological findings of this case are discussed.


Subject(s)
Humans , Male , Adult , Tinnitus/complications , Inferior Colliculi/pathology , Magnetic Resonance Spectroscopy , Central Nervous System Diseases , Neoplasms
5.
Prev Med Rep ; 28: 101843, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35634215

ABSTRACT

Background: The pandemic propagation of SARS-CoV-2 led to the adoption of a myriad of non-pharmacological interventions (NPIs, e.g., social distancing, mobility restrictions, gathering restrictions) in the Americas. Using national epidemiological data, here we report the impact of the layered adoption of multiple NPIs aimed at curving SARS-CoV-2 transmission in Yucatan State, Mexico. Methods: Data from suspected and laboratory confirmed COVID-19 cases during 2020 were analyzed by age groups and sex, clinical signs, and symptoms as well as outcome. The impact of NPIs was quantified using time-varying reproduction numbers (R t) estimated as a time-series and by sectors of the city. Findings: A total of 69,602 suspected cases were reported, 39.3% were laboratory-confirmed. Men were hospitalized (60.2%), more severely ill (3% vs 1.9%) and more likely to die (62%) than women. Early in the outbreak, all sectors in Merida had R t estimates above unity. Once all NPÍs were in place, R t values were dramatically reduced below one, and in the last interval transmission estimates of R t remained below one in all sectors. Interpretation: In the absence of a COVID-19 vaccination program, the combination and wide adherence of NPÍs led to a low and stable trend in SARS-CoV-2 transmission that did not overwhelm the health sector. Our study reflects that a controlled and planned ease of restrictions to balance health, social and economic recovery resulted in a single wave of transmission that prolonged at low and stable levels. Funding: GVP received funding from Emory University via the MP3 Initiative.

7.
Rev Med Chil ; 150(12): 1619-1624, 2022 Dec.
Article in Spanish | MEDLINE | ID: mdl-37906783

ABSTRACT

BACKGROUND: In those patients who do not have timely access to primary angioplasty, the pharmaco-invasive approach, that is, the use of thrombolysis as a bridging measure prior to the coronary angiography, is a safe alternative. AIM: To describe the features of patients with an acute ST-elevation myocardial infarction (STEMI) treated with a pharmaco-invasive strategy. MATERIAL AND METHODS: Descriptive observational study of 144 patients with mean age of 46 years with STEMI who received a dose of thrombolytic prior to their referral for primary angioplasty at a public hospital between 2018 and 2021. RESULTS: There were no differences the clinical presentation according to the Killip score at admission between thrombolyzed and non-thrombolyzed patients (p = ns). Fifty-three percent of non-thrombolyzed patients were admitted with an occluded vessel (TIMI 0) compared with 27% of thrombolyzed patients (p < 0.001). The thrombolyzed group required significantly less use of thromboaspiration (3.5 and 8.4% respectively; p = 0.014). Despite this, 91 and 92% of non-thrombolyzed and thrombolyzed patients achieved a post-angioplasty TIMI 3 flow. Long-term survival was 91 and 86% in thrombolyzed and non-thrombolyzed patients, respectively (p = ns). CONCLUSIONS: The pharmaco-invasive strategy is a safe alternative when compared to primary angioplasty in centers that don't have timely access to Interventional Cardiology.


Subject(s)
Myocardial Infarction , ST Elevation Myocardial Infarction , Humans , Middle Aged , ST Elevation Myocardial Infarction/drug therapy , Thrombolytic Therapy , Myocardial Infarction/drug therapy , Fibrinolytic Agents/therapeutic use , Treatment Outcome , Coronary Angiography
8.
Clin Transl Oncol ; 24(5): 836-845, 2022 May.
Article in English | MEDLINE | ID: mdl-34792726

ABSTRACT

PURPOSE: Radiation-induced toxicity (RIT) is usually assessed by inspection and palpation. Due to their subjective and unquantitative nature, objective methods are required. This study aimed to determine whether a quantitative tool is able to assess RIT and establish an underlying BED-response relationship in breast cancer. METHODS: Patients following seven different breast radiation protocols were recruited to this study for RIT assessment with qualitative and quantitative examination. The biologically equivalent dose (BED) was used to directly compare different radiation regimens. RIT was subjectively evaluated by physicians using the Radiation Therapy Oncology Group (RTOG) late toxicity scores. Simultaneously an objective multiprobe device was also used to quantitatively assess late RIT in terms of erythema, hyperpigmentation, elasticity and skin hydration. RESULTS: In 194 patients, in terms of the objective measurements, treated breasts showed higher erythema and hyperpigmentation and lower elasticity and hydration than untreated breasts (p < 0.001, p < 0.001, p < 0.001, p = 0.019, respectively). As the BED increased, Δerythema and Δpigmentation gradually increased as well (p = 0.006 and p = 0.002, respectively). Regarding the clinical assessment, the increase in BED resulted in a higher RTOG toxicity grade (p < 0.001). Quantitative assessments were consistent with RTOG scores. As the RTOG toxicity grade increased, the erythema and pigmentation values increased, and the elasticity index decreased (p < 0.001, p = 0.016, p = 0.005, respectively). CONCLUSIONS: The multiprobe device can be a sensitive and simple tool for research purpose and quantitatively assessing RIT in patients undergoing radiotherapy for breast cancer. Physician-assessed toxicity scores and objective measurements revealed that the BED was positively associated with the severity of RIT.


Subject(s)
Breast Neoplasms , Hyperpigmentation , Radiation Injuries , Breast , Breast Neoplasms/radiotherapy , Erythema/etiology , Female , Humans , Hyperpigmentation/etiology , Skin
9.
Appl Radiat Isot ; 178: 109936, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34592691

ABSTRACT

Investigations regarding the feasibility, reliability, and accuracy of Fricke gel dosimeter layers for stereotactic radiosurgery are presented. A representative radiosurgery plan consisting of two targets has been investigated. Absorbed dose distributions measured using radiochromic films and gelatin Fricke Gel dosimetry in layers have been compared with dose distributions calculated by using a treatment planning system and Monte Carlo simulations. The different dose distributions have been compared by means of the gamma index demonstrating that gelatin Fricke gel dosimeter layers showed agreements of 100%, 100%, and 93%, with dose and distance tolerances of 2% and 2 mm, with respect to film dosimetry, treatment planning system and Monte Carlo simulations, respectively. The capability of the developed system for three-dimensional dose mapping was shown, obtaining promising results when compared with well-established dosimetry methods. The obtained results support the viability of Fricke gel dosimeter layers analyzed by optical methods for stereotactic radiosurgery.


Subject(s)
Fluorescent Dyes/chemistry , Gels/chemistry , Phenols/chemistry , Radiation Dosimeters/standards , Radiosurgery/methods , Sulfoxides/chemistry , Feasibility Studies , Humans , Monte Carlo Method , Phantoms, Imaging , Reproducibility of Results
12.
Andes Pediatr ; 92(3): 359-366, 2021 Jun.
Article in English, Spanish | MEDLINE | ID: mdl-34479241

ABSTRACT

INTRODUCTION: Prader-Willi Syndrome (PWS) is the most common cause of genetic obesity. Hyperphagia and obe sity are the most associated concepts with this condition. However, undernutrition secondary to severe hypotonia and feeding difficulties is the predominant initial feature. OBJECTIVE: to reprodu ce and communicate the nutritional phases on a series of Chilean cases with PWS. PATIENTS AND METHOD: Cross-sectional study in which clinical records of PWS individuals under nutritional con trol at the Clínica Santa María in Santiago, Chile between 2017 and 2018 were analyzed. The anthro pometric references of the World Health Organization were used to carry out the nutritional as sessment. The classification into nutritional phases was according to the Miller criteria. RESULTS: 24 patients from infants to adults were included. All children aged under 9 months were in phase I and had malnutrition or were eutrophic; those between 9 and 25 months were classified in phase 2a; pa tients between 2.1 and 4.5 years were distributed between phases 1 and 2 and 66% were eutrophic; those between 4.5 to 8 years, 80% were in phase 2a and 2b and obesity begins to appear, and patients over 8 years of age, 75% were in phase 3 and all are overweight or obese. There was an association bet ween nutritional phase and age but not between it and nutritional status. CONCLUSIONS: In our series, the nutritional phases described according to age were reproduced according to those internationally described. There was no association between nutritional status and age.


Subject(s)
Hyperphagia/etiology , Malnutrition/etiology , Pediatric Obesity/etiology , Prader-Willi Syndrome/physiopathology , Adolescent , Adult , Age Factors , Child , Child, Preschool , Cross-Sectional Studies , Disease Progression , Female , Humans , Hyperphagia/diagnosis , Infant , Infant, Newborn , Male , Malnutrition/diagnosis , Pediatric Obesity/diagnosis , Prader-Willi Syndrome/diagnosis , Prader-Willi Syndrome/psychology , Young Adult
13.
Rev Med Chil ; 149(4): 520-526, 2021 Apr.
Article in Spanish | MEDLINE | ID: mdl-34479339

ABSTRACT

BACKGROUND: Transfemoral transcatheter aortic valve implantation (TAVI) is the standard of treatment for patients with symptomatic severe aortic stenosis (AE) and intermediate or high surgical risk. The use of conscious sedation (CS) could reduce complications and allow an early discharge of these patients. AIM: To report our experience with TAVI under conscious sedation. MATERIAL AND METHODS: Review of medical records of 15 patients aged 79 ± 6 years (53% women) undergoing a transfemoral TAVI implant under conscious sedation. RESULTS: The indications for the procedure were severe AE in 13 patients and biological prosthetic dysfunction in two. The mean Thoracic Surgeons predicted risk of mortality score was 7.3. The valves used were Edwards Sapien 3 in three patients, Medtronic Evolut in five, Boston Acurate Neo in four and Meril Myval in three. A successful implant was achieved in all cases and there were no hospital mortality or pacemaker requirements. One patient had a stroke, and one patient had a vascular access complication. Early discharge (< 72 h) was achieved in 80% of patients. CONCLUSIONS: TAVI under conscious sedation was a safe procedure and associated with a complication rate similar to previous reports, allowing for an early hospital discharge in most patients.


Subject(s)
Aortic Valve Stenosis , Heart Valve Prosthesis , Transcatheter Aortic Valve Replacement , Aortic Valve Stenosis/surgery , Conscious Sedation , Female , Humans , Male , Treatment Outcome
14.
Rev Gastroenterol Mex (Engl Ed) ; 86(4): 370-377, 2021.
Article in English | MEDLINE | ID: mdl-34384724

ABSTRACT

INTRODUCTION AND AIMS: Primary liver cancer is a public health problem in Mexico and the world. Liver transplantation (LT) is the ideal treatment for early hepatocellular carcinoma (HCC). Our aim was to evaluate the characteristics of patients with HCC and cholangiocarcinoma (CC) at two centers and identify transplantation candidates. MATERIALS AND METHODS: A retrospective observational study was conducted at the Hepatology Center (HC) and the University Center Against Cancer (UCAC), within the time frame of 2012-2018. HCC or intrahepatic CC was confirmed in 109 patients. Staging classifications, transplant selection models, and a predictive model for post-LT recurrence were applied to the HCC patients. RESULTS: Of the total population, 93% (n=102) presented with cirrhosis, 86% (n=94) had HCC (HC: 58%, UCAC: 42%), and 14% (n=15) had intrahepatic CC (HC: 40%, UCAC: 60%). Of the HC patients with HCC, Okuda I-II, BCLC A-B, and AFP levels <100ng/m predominated, whereas Okuda II-III, BCLC C-D, and AFP levels >1000ng/mL predominated in the UCAC patients. Half of the HC population with HCC met the criteria for LT, in contrast to 23% of the UCAC patients. Fifteen patients were evaluated for LT, and at present, six have undergone transplantation. CONCLUSIONS: The most frequent primary liver tumor was HCC. Patients from the HC presented with earlier-stage disease and a high number of them met the criteria for LT. Only patients from the HC underwent transplantation.


Subject(s)
Bile Duct Neoplasms , Carcinoma, Hepatocellular , Gastroenterology , Liver Neoplasms , Carcinoma, Hepatocellular/therapy , Humans , Liver Neoplasms/therapy , Neoplasm Recurrence, Local , alpha-Fetoproteins
15.
Nanotechnology ; 32(40)2021 Jul 14.
Article in English | MEDLINE | ID: mdl-34186516

ABSTRACT

The present study was aimed to develop nitrogen-doped nanostructured ZnO thin films. These films were produced in a sequential procedure involving the atomic layer deposition technique, and a hydrothermal process supported by microwave heating. Employing the atomic layer deposition technique, through self-limited reactions of diethylzinc (DEZn) and H2O, carried out at 3.29 × 10-4atm and 190 °C, a high-quality ZnO seed was grown on a Si (100) substrate, producing a textured film. In a second stage, columnar ZnO nanostructures were grown perpendicularly oriented to the silicon substrate on those films, using a solvothermal process in a microwave heating facility, employing Zn(NO3)2as zinc precursor, while hexamethylenetetramine (HMTA) was used to produce the bridging of Zn2+ions. The consequence of N-doping concentration on the physicochemical properties of ZnO thin films was studied. The manufactured films were structurally analyzed by scanning electron microscopy and x-ray diffraction. Also, x-ray photoelectron spectroscopy, Raman, and UV-vis spectroscopies were used to provide further insight on the effect of nitrogen doping. The N-doped films displayed textured wurtzite-like structures that changes their preferential growth from the (002) to the (100) crystallographic plane, apparently promoted by the increase of nitrogen precursor. It is also shown that nitrogen-doped films undergo a reduction in their bandgap, compared to ZnO. The methodology presented here provides a viable way to perform high-quality N-ZnO nanostructured thin films.

16.
Rev. méd. Chile ; 149(4): 520-526, abr. 2021. tab
Article in Spanish | LILACS | ID: biblio-1389479

ABSTRACT

Background: Transfemoral transcatheter aortic valve implantation (TAVI) is the standard of treatment for patients with symptomatic severe aortic stenosis (AE) and intermediate or high surgical risk. The use of conscious sedation (CS) could reduce complications and allow an early discharge of these patients. Aim: To report our experience with TAVI under conscious sedation. Material and Methods: Review of medical records of 15 patients aged 79 ± 6 years (53% women) undergoing a transfemoral TAVI implant under conscious sedation. Results: The indications for the procedure were severe AE in 13 patients and biological prosthetic dysfunction in two. The mean Thoracic Surgeons predicted risk of mortality score was 7.3. The valves used were Edwards Sapien 3 in three patients, Medtronic Evolut in five, Boston Acurate Neo in four and Meril Myval in three. A successful implant was achieved in all cases and there were no hospital mortality or pacemaker requirements. One patient had a stroke, and one patient had a vascular access complication. Early discharge (< 72 h) was achieved in 80% of patients. Conclusions: TAVI under conscious sedation was a safe procedure and associated with a complication rate similar to previous reports, allowing for an early hospital discharge in most patients.


Subject(s)
Humans , Male , Female , Aortic Valve Stenosis/surgery , Heart Valve Prosthesis , Transcatheter Aortic Valve Replacement , Conscious Sedation , Treatment Outcome
17.
Article in English, Spanish | MEDLINE | ID: mdl-33676785

ABSTRACT

INTRODUCTION AND AIMS: Primary liver cancer is a public health problem in Mexico and the world. Liver transplantation (LT) is the ideal treatment for early hepatocellular carcinoma (HCC). Our aim was to evaluate the characteristics of patients with HCC and cholangiocarcinoma (CC) at two centers and identify transplantation candidates. MATERIALS AND METHODS: A retrospective observational study was conducted at the Hepatology Center (HC) and the University Center Against Cancer (UCAC), within the time frame of 2012-2018. HCC or intrahepatic CC was confirmed in 109 patients. Staging classifications, transplant selection models, and a predictive model for post-LT recurrence were applied to the HCC patients. RESULTS: Of the total population, 93% (n = 102) presented with cirrhosis, 86% (n = 94) had HCC (HC: 58%, UCAC: 42%), and 14% (n = 15) had intrahepatic CC (HC: 40%, UCAC: 60%). Of the HC patients with HCC, Okuda I-II, BCLC A-B, and AFP levels < 100 ng/m predominated, whereas Okuda II-III, BCLC C-D, and AFP levels > 1,000 ng/mL predominated in the UCAC patients. Half of the HC population with HCC met the criteria for LT, in contrast to 23% of the UCAC patients. Fifteen patients were evaluated for LT, and at present, six have undergone transplantation. CONCLUSIONS: The most frequent primary liver tumor was HCC. Patients from the HC presented with earlier-stage disease and a high number of them met the criteria for LT. Only patients from the HC underwent transplantation.

18.
Int J Biol Macromol ; 169: 75-84, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33338526

ABSTRACT

In this research, the adsorption of three synthetic dyes dissolved in an aqueous solution on chitosan cryogel beads (Q-C-EGDE) was compared. The effect of the pH of the solution on the adsorption capacity of each dyes was analyzed. Furthermore, the kinetics and adsorption isotherms were compared, at temperatures of 283.15 K, 303.15 K and 323.15 K, and the kinetic and adsorption equilibrium data were fitted to three mathematical models, respectively. The biosorbent was characterized by scanning electron microscopy (SEM), the nitrogen physisorption BET method and Fourier transform infrared spectroscopy (FTIR). The characterization results show that the cryogel is composed of low-surface, macroporous, porous grooved walls. The functional groups that took part in the adsorption were mainly amino groups (NH3+). When comparing the adsorption capacities, it was found that the dyes adsorb in the following order Blue 1 > Red 2 > Yellow 5 reaching capacities from 1600 mg/L to 850 mg/L. The results of the adsorption and mathematical modelling suggest that the process is regulated mainly by physisorption and is largely limited by mass transfer mechanisms within the cryogel, where the electrostatic charges present affect adsorption. The latter was corroborated by the Monte Carlo simulation.


Subject(s)
Chitosan/chemistry , Coloring Agents/chemistry , Cryogels/chemistry , Adsorption/drug effects , Hydrogen-Ion Concentration , Kinetics , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared/methods , Temperature , Water Pollutants, Chemical/chemistry , Water Purification/methods
20.
Anal Biochem ; 608: 113897, 2020 11 01.
Article in English | MEDLINE | ID: mdl-32780997

ABSTRACT

The azo dyes, Yellow 5 (Y5), Red 2 (R2) and Blue 1 (B1), quantified in solutions and in mixtures of binary dyes, were studied by means of UV-Vis spectroscopy. In this work was used a CIE algorithm developed in Visual Basic for Applications (VBA). The CIE algorithm is based on the tristimulus chromaticity diagram, as an alternative to the shielding effect that arises in dye mixtures, and it can also be applied to complex quantification methods such as HPLC (High Performance Liquid Chromatography). The results obtained through of the algorithm, showed a higher accuracy from 97 to 99% in relation with similar UV-Vis quantification methods. In contrast, linear methods only managed to reach an accuracy from 78 to 98%. Additionally, the algorithm yielded significant similar values to the UHPLC reference method. The results showed that the method CIE algorithm was accessible and reliable to quantify binary mixtures of the dyes used which suggests the possibility to apply this method on other dyes, within the limits of quantification obtained in this study (0.076-24.56 mg/L) and the pH values from 2 to 10.


Subject(s)
Azo Compounds/analysis , Colorimetry/methods , Colorimetry/standards , Spectrophotometry, Ultraviolet/methods , Spectrophotometry, Ultraviolet/standards , Spectrophotometry/methods , Spectrophotometry/standards , Algorithms , Calibration , Chromatography, High Pressure Liquid , Limit of Detection , Programming Languages
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