Video approach to chemiluminescence detection using a low-cost complementary metal oxide semiconductor (CMOS)-based camera: determination of paracetamol in pharmaceutical formulations

[EN] A new system for continuous flow chemiluminescence detection, based on the use of a simple and low-priced lens-free digital camera (with complementary metal oxide semiconductor technology) as a detector, is proposed for the quantitative determination of paracetamol in commercial pharmaceutical formulations. Through the camera software, AVI video files of the chemiluminescence emission are captured and then, using friendly ImageJ public domain software (from National Institutes for Health), properly processed in order to extract the analytical information. The calibration graph was found to be linear over the range 0.01¿ 0.10 mg L¿1 and over the range 1.0¿100.0 mg L¿1 of paracetamol, the limit of detection being 10 ¿g L¿1. No significative interferences were found. Paracetamol was determined in three different pharmaceutical formulations: Termalgin®, Efferalgan® and Gelocatil®. The obtained results compared well with those declared on the formulation label and with those obtained through the official analytical method of British Pharmacopoeia.S3891389840915Worsfold PJ, Robards K. Analytical applications of liquid phase chemiluminescence. Anal Chim Acta. 1992;266:147–73. doi: 10.1016/0003-2670(92)85040-D .Fuster Mestre Y, Lahuerta-Zamora L, Martínez Calatayud J. Flow-chemiluminescence: a growing modality of pharmaceutical analysis. Luminescence. 2001;16(3):213–35. doi: 10.1002/bio.608 .Roda A, Pasini P, Mirasoli M, Michelini E, Guardigli M. Biotechnological applications of bioluminescence and chemiluminescence. Trends Biotechnol. 2004;22(6):295–303. doi: 10.1016/j.tibtech.2004.03.011 .Yinhuan L, Weifen N, Jiuru L. Talanta. 2007;71:1124–9.Gámiz-Gracia L, García-Campaña AM, Huertas-Pérez JF, Lara FJ. Chemiluminescence detection in liquid chromatography: applications to clinical, pharmaceutical, environmental and food analysis—a review. Anal Chim Acta. 2009;640(1–2):7–28. doi: 10.1016/j.aca.2009.03.017 .Roda A, Guardigli M. Analytical chemiluminescence and bioluminescence: latest achievements and new horizons. Anal Bioanal Chem. 2012;402:69–76. doi: 10.1007/s00216-011-5455-8 .Iranifam M. Revisiting flow-chemiluminescence techniques: pharmaceutical analysis. Luminescence. 2012;28(6):798–820. doi: 10.1002/bio.2441 .Byrne L, Barker J, Pennarun-Thomas G, Diamond D. Digital imaging as a detector for generic analytical measurements. TrAC–Trend Anal Chem. 2000;19:517–22. doi: 10.1016/S0165-9936(00)00019-4 .Rodrigues ERGO, Lapa RAS. CMOS arrays as chemiluminescence detectors on microfluidic devices. Anal Bioanal Chem. 2010;397:381–8. doi: 10.1007/s00216-010-3518-x .Capitán-Vallvey LF, López-Ruiz N, Martínez-Olmos A, Erenas MM, Palma AJ. Recent developments in computer vision-based analytical chemistry: a tutorial review. Anal Chim Acta. 2015;899:23–56. doi: 10.1016/j.aca.2015.10.009 .Lahuerta-Zamora L, Alemán López PA, Antón Fos GM, Martín Algarra R, Mellado-Romero AM, Martínez Calatayud J. Quantitative colorimetric-imaging analysis of nickel in iron meteorites. Talanta. 2011;83(5):1575–9. doi: 10.1016/j.talanta.2010.11.058 .Lahuerta-Zamora L, Pérez Gracia T. Using digital photography to implement the McFarland method. J R Soc Interface. 2012;9:1892–7. doi: 10.1098/rsif.2011.0809 .Wongwilai W, Lapanantnoppakhun S, Grudpan S, Grudpan K. Webcam camera as a detector for a simple lab-on-chip time based approach. Talanta. 2010;81:1137–41. doi: 10.1016/j.talanta.2010.01.058 .Balsam J, Bruck HA, Kostov Y, Rasooly A. Image stacking approach to increase sensitivity of fluorescence detection using a low cost complementary metal-oxide-semiconductor (CMOS) webcam. Sens Actuators B Chem. 2012;171–172:141–7. doi: 10.1016/j.snb.2012.02.003 .Marquette CA, Blum LJ. Applications of the luminol chemiluminescent reaction in analytical chemistry. Anal Bioanal Chem. 2006;385:546–54. doi: 10.1007/s00216-006-0439-9 .Gregorio Alapont A, Lahuerta-Zamora L, Martínez Calatayud J. Indirect determination of paracetamol in pharmaceutical formulations by inhibition of the system luminol–H2O2–Fe(CN)6 3− chemiluminescence. J Pharm Biomed Anal. 1999;21:311–7. doi: 10.1016/s0731-7085(99)00124-7 .British Pharmacopoeia 1993. HM stationery office. London; 1993. vol. II, p. 1043

Integració vocal amb tecnologia SPHINX. Aplicació pràctica a vivendes intel·ligents

Aquest projecte tracta el desenvolupament d'una interfície vocal per a un habitatge domotitzat, mitjançant el programari lliure SPHINX com a base del reconeixement de la veu. El reconeixement de veu es processa per poder dictar les ordres d'una forma intuïtiva i amb llenguatge humà.Mellado Romero, M. (2014). Integració vocal amb tecnologia SPHINX. Aplicació pràctica a vivendes intel·ligents. http://hdl.handle.net/10251/39584.Archivo delegad

Galileo, a data platform for viewing news on social networks

This article aims to introduce Galileo, a platform for extracting and organizing news media data on social networks. Galileo integrates publications made on the main social networks used in the information ecosystem, namely Facebook, Twitter, and Instagram. Currently, the system includes 97 media outlets from nine countries: Brazil, Chile, Germany, Japan, Mexico, South Korea, Spain, United Kingdom, and United States. Galileo uses a Twitter API and the service CrowdTangle to download Facebook and Instagram posts. This data is stored in a local database and can be accessed through a user-friendly interface, which allows for the analysis of different characteristics of the posts, such as their text, source popularity, and temporal dimension. Galileo is a tool for researchers interested in understanding news cycles and analyzing news content on social networks.

A problem on the approximation of n-roots based on the Viète's work

In this paper, after giving a brief approach about the historical question of how different authors and cultures handled approximations of the n-th root of N := An + R, we consider the particular case of the approximation of n v N by A + R d (here n, A, d are positive integers, with n = 2, d = (A + 1)n - An - 1, and 0 < R = d), explicitly considered by Viète in his De Numerosa Potestatum. Viète established in one of the precepts of his work that the n-th root is placed between A + R d+1 and A+ R d . Indeed, it is easily seen that, of course, A + R d+1 = n v N , but unfortunately n v N can be greater than A + R d when n = 3. Then the question arises whether we are able or not of determining what values of R (fixing the integer values n and A, so also d) give a true approximation by excess when n v N is estimated as A + R d , that is, to find those values of R producing an excess in relation with the exact value of the root. We give a complete answer to the cases n = 7, and we present without proof the main result for a general n.This work has been supported by the grant MTM2017-84079-P (AEI/FEDER, UE) from Ministerio de Ciencia, Innovación y Universidades (Spain).Postprint (published version

Molecular and Functional Characterization of Novel Fructosyltransferases and Invertases from Agave tequilana

Fructans are the main storage polysaccharides found in Agave species. The synthesis of these complex carbohydrates relies on the activities of specific fructosyltransferase enzymes closely related to the hydrolytic invertases. Analysis of Agave tequilana transcriptome data led to the identification of ESTs encoding putative fructosyltransferases and invertases. Based on sequence alignments and structure/function relationships, two different genes were predicted to encode 1-SST and 6G-FFT type fructosyltransferases, in addition, 4 genes encoding putative cell wall invertases and 4 genes encoding putative vacuolar invertases were also identified. Probable functions for each gene, were assigned based on conserved amino acid sequences and confirmed for 2 fructosyltransferases and one invertase by analyzing the enzymatic activity of recombinant Agave protein s expressed and purified from Pichia pastoris. The genome organization of the fructosyltransferase/invertase genes, for which the corresponding cDNA contained the complete open reading frame, was found to be well conserved since all genes were shown to carry a 9 bp mini-exon and all showed a similar structure of 8 exons/7 introns with the exception of a cell wall invertase gene which has 7 exons and 6 introns. Fructosyltransferase genes were strongly expressed in the storage organs of the plants, especially in vegetative stages of development and to lower levels in photosynthetic tissues, in contrast to the invertase genes where higher levels of expression were observed in leaf tissues and in mature plants

Computer vision-based analytical chemistry applied to determining iron in commercial pharmaceutical formulations

[EN] Two different computer vision-based analytical chemistry (CVAC) methods were developed to quantify iron in the commercial pharmaceutical formulations Ferbisol (R) and Ferro sanol (R). The methods involve using a digital camera or a desktop scanner to capture a digital image of a series of Fe2+ standard solutions and the unknown sample upon reaction with o-phenanthroline. The images are processed with appropriate software (e.g., the public domain programme ImageJ, from NIH) to obtain a numerical value (analytical signal) based on colour intensity. The fact that such a value is proportional to the analyte concentration allows one to construct a calibration graph from the standards and interpolate the value for the sample in order to determine its concentration. The results thus obtained were compared with those provided by a spectrophotometric method and the US Pharmacopoeia's recommended method. The differences never exceeded 2%. The two proposed methods are simple and inexpensive; also, they provide an effective instrumental alternative to spectrophotometric methods which can be especially beneficial in those cases where purchasing and maintaining a spectrophotometer is unaffordable.Solana-Altabella, A.; Sanchez-Iranzo, M.; Bueso-Bordils, J.; Lahuerta-Zamora, L.; Mellado Romero, AM. (2018). Computer vision-based analytical chemistry applied to determining iron in commercial pharmaceutical formulations. Talanta. 188:349-355. https://doi.org/10.1016/j.talanta.2018.06.008S34935518

The six books of Diophantus’ Arithmetic increased and reduced to specious: the lost manuscript of Jacques Ozanam (1640–1718)

The version of record is available online at: http://dx.doi.org/10.1007/s00407-021-00274-3The introduction of a new analytical method, due fundamentally to François Viète and René Descartes and the later dissemination of their works, resulted in a profound change in the way of thinking and doing mathematics. This change, known as process of algebrization, occurred during the seventeenth and early eighteenth centuries and led to a great transformation in mathematics. Among many other consequences, this process gave rise to the treatment of the results in the classic treatises with the new analytical method, which allowed new visions of such treatises and the obtaining of new results. Among those treatises is the Arithmetic of Diophantus of Alexandria (approx. 200–284) which was written, using the new algebraic language, by the French mathematician Jacques Ozanam (1640–1718), who in addition to profusely increasing the original problems of Diophantus, solved them in a general way, thus obtaining many geometric consequences. The work is handwritten, it has never been published, it has been lost for almost 300 years, and the known references show its importance. We will show that Ozanam’s manuscript was quoted as an important work on several occasions by others mathematicians of the time, among whom G. W. Leibniz stands out. Once the manuscript has been located, our aim in this article is to show and analyze this work of Ozanam, its content, its notation and its structure and how, through the new algebraic method, he not only solved and expanded the questions proposed by Diophantus, but also introduced a connection between the algebraic solutions and what he called geometric determinations by obtaining loci from the solutions.Peer ReviewedPostprint (author's final draft

Durability of glass fiber reinforced cement (GRC) containing a high proportion of pozzolans

[EN] Glass fiber reinforced cement (GRC) is an excellent composite for architects and engineers because it can be molded to produce laminar panels or to create complicated designs. GRC is a fine concrete reinforced with alkali-resistant glass fibers at 3¿5% per mass. However, fiber durability is limited because of the aggressiveness of the alkaline medium produced during Portland cement hydration (effect of portlandite). The objective of this study is to assess GRC with high Portland cement replacement with pozzolans (ground fly ash or a mixture of ground fly ash and sonicated silica fume) in order to reduce the corrosion of the fibers. The selected high-content pozzolan (60% replacement) composites were tested under different conditions: aging, drying¿wetting, freezing¿thawing, and chemical attack (ammonium chloride and sulfuric acid). The modulus of rupture and toughness were determined. Composite behavior showed that the samples with pozzolans not only better resisted aging, but also physical and chemical attacks, and specimens presented a better modulus of rupture and toughness than the samples prepared with 100% Portland cement (control specimens). Due to the good behavior in durability terms, the high pozzolan content GRC products are suitable in potential corrosive environments for sunscreens, drainage channels, cable trays, sound barriers, or pavements.This research was funded by Spanish Ministry of Education and Science and FEDER funds (Project BIA 2004-00520)Lalinde, LF.; Mellado Romero, AM.; Borrachero Rosado, MV.; Monzó Balbuena, JM.; Paya Bernabeu, JJ. (2022). Durability of glass fiber reinforced cement (GRC) containing a high proportion of pozzolans. Applied Sciences. 12(7). https://doi.org/10.3390/app1207369612