Modern microwave methods in solid state inorganic materials chemistry: from fundamentals to manufacturing

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Evidence for the existence of powder sub-populations in micronized materials : Aerodynamic size-fractions of aerosolized powders possess distinct physicochemical properties

This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.Purpose: To investigate the agglomeration behaviour of the fine ( 12.8 µm) particle fractions of salmeterol xinafoate (SX) and fluticasone propionate (FP) by isolating aerodynamic size fractions and characterising their physicochemical and re-dispersal properties. Methods: Aerodynamic fractionation was conducted using the Next Generation Impactor (NGI). Re-crystallized control particles, unfractionated and fractionated materials were characterized for particle size, morphology, crystallinity and surface energy. Re-dispersal of the particles was assessed using dry dispersion laser diffraction and NGI analysis. Results: Aerosolized SX and FP particles deposited in the NGI as agglomerates of consistent particle/agglomerate morphology. SX particles depositing on Stages 3 and 5 had higher total surface energy than unfractionated SX, with Stage 5 particles showing the greatest surface energy heterogeneity. FP fractions had comparable surface energy distributions and bulk crystallinity but differences in surface chemistry. SX fractions demonstrated higher bulk disorder than unfractionated and re-crystallized particles. Upon aerosolization, the fractions differed in their intrinsic emission and dispersion into a fine particle fraction (< 5.0 µm). Conclusions: Micronized powders consisted of sub-populations of particles displaying distinct physicochemical and powder dispersal properties compared to the unfractionated bulk material. This may have implications for the efficiency of inhaled drug deliveryPeer reviewe

Sperm DNA fragmentation: a new guideline for clinicians

Sperm DNA integrity is crucial for fertilization and development of healthy offspring. The spermatozoon undergoes extensive molecular remodeling of its nucleus during later phases of spermatogenesis, which imparts compaction and protects the genetic content. Testicular (defective maturation and abortive apoptosis) and post-testicular (oxidative stress) mechanisms are implicated in the etiology of sperm DNA fragmentation (SDF), which affects both natural and assisted reproduction. Several clinical and environmental factors are known to negatively impact sperm DNA integrity. An increasing number of reports emphasizes the direct relationship between sperm DNA damage and male infertility. Currently, several assays are available to assess sperm DNA damage, however, routine assessment of SDF in clinical practice is not recommended by professional organizations. This article provides an overview of SDF types, origin and comparative analysis of various SDF assays while primarily focusing on the clinical indications of SDF testing. Importantly, we report four clinical cases where SDF testing had played a significant role in improving fertility outcome. In light of these clinical case reports and recent scientific evidence, this review provides expert recommendations on SDF testing and examines the advantages and drawbacks of the clinical utility of SDF testing using Strength-Weaknesses-Opportunities-Threats (SWOT) analysis

Contribution of infection and vaccination to population-level seroprevalence through two COVID waves in Tamil Nadu, India.

This study employs repeated, large panels of serological surveys to document rapid and substantial waning of SARS-CoV-2 antibodies at the population level and to calculate the extent to which infection and vaccination separately contribute to seroprevalence estimates. Four rounds of serological surveys were conducted, spanning two COVID waves (October 2020 and April-May 2021), in Tamil Nadu (population 72 million) state in India. Each round included representative populations in each district of the state, totaling ≥ 20,000 persons per round. State-level seroprevalence was 31.5% in round 1 (October-November 2020), after India's first COVID wave. Seroprevalence fell to 22.9% in round 2 (April 2021), a roughly one-third decline in 6 months, consistent with dramatic waning of SARS-Cov-2 antibodies from natural infection. Seroprevalence rose to 67.1% by round 3 (June-July 2021), with infections from the Delta-variant induced second COVID wave accounting for 74% of the increase. Seroprevalence rose to 93.1% by round 4 (December 2021-January 2022), with vaccinations accounting for 63% of the increase. Antibodies also appear to wane after vaccination. Seroprevalence in urban areas was higher than in rural areas, but the gap shrunk over time (35.7 v. 25.7% in round 1, 89.8% v. 91.4% in round 4) as the epidemic spread even in low-density rural areas

Delay in diagnosis of tuberculosis in Rawalpindi, Pakistan

<p>Abstract</p> <p>Background</p> <p>Delay in diagnosis and treatment of tuberculosis (TB) may enhance the chances of morbidity and mortality and play a key role in continuous transmission of the bacilli. The objective of this study was to describe health care seeking behavior of suspected TB patients and initial diagnostic work up prior to consultation and diagnosis at National TB Center (NTC).</p> <p>Findings</p> <p>Interviews of 252 sputum smear positive patients were taken from NTC, Rawalpindi. The duration between on-set of symptoms and start of treatment was considered as the total delay and correlated with general characteristics of TB patients. The proportion of males and females were 49.6% and 50.4% with median age of 25 and 24 years respectively. A median delay of 56 days (8 weeks) was observed which was significantly associated with age, cough and fever. More than 50% of the current patients had a history of contact with previously diagnosed TB patients. The majority of patients (63%) visited health care providers within three weeks of appearance of symptoms but only thirty five percent were investigated for TB diagnosis.</p> <p>Conclusion</p> <p>Cough and fever are being ignored as likely symptoms of TB by patients as well as health care providers resulting in delay. Engaging private practitioners through public private mix (PPM) approach for expansion of TB diagnosis and increasing public awareness could be more beneficial to reduce delay.</p

Disposable sensors in diagnostics, food and environmental monitoring

Disposable sensors are low‐cost and easy‐to‐use sensing devices intended for short‐term or rapid single‐point measurements. The growing demand for fast, accessible, and reliable information in a vastly connected world makes disposable sensors increasingly important. The areas of application for such devices are numerous, ranging from pharmaceutical, agricultural, environmental, forensic, and food sciences to wearables and clinical diagnostics, especially in resource‐limited settings. The capabilities of disposable sensors can extend beyond measuring traditional physical quantities (for example, temperature or pressure); they can provide critical chemical and biological information (chemo‐ and biosensors) that can be digitized and made available to users and centralized/decentralized facilities for data storage, remotely. These features could pave the way for new classes of low‐cost systems for health, food, and environmental monitoring that can democratize sensing across the globe. Here, a brief insight into the materials and basics of sensors (methods of transduction, molecular recognition, and amplification) is provided followed by a comprehensive and critical overview of the disposable sensors currently used for medical diagnostics, food, and environmental analysis. Finally, views on how the field of disposable sensing devices will continue its evolution are discussed, including the future trends, challenges, and opportunities

Male oxidative stress infertility (MOSI): proposed terminology and clinical practice guidelines for management of idiopathic male infertility

Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diagnose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role in the etiology of male infertility, with 30% to 80% of infertile men having elevated seminal reactive oxygen species levels. OS can negatively affect fertility via a number of pathways, including interference with capacitation and possible damage to sperm membrane and DNA, which may impair the sperm's potential to fertilize an egg and develop into a healthy embryo. Adequate evaluation of male reproductive potential should therefore include an assessment of sperm OS. We propose the term Male Oxidative Stress Infertility, or MOSI, as a novel descriptor for infertile men with abnormal semen characteristics and OS, including many patients who were previously classified as having idiopathic male infertility. Oxidation-reduction potential (ORP) can be a useful clinical biomarker for the classification of MOSI, as it takes into account the levels of both oxidants and reductants (antioxidants). Current treatment protocols for OS, including the use of antioxidants, are not evidence-based and have the potential for complications and increased healthcare-related expenditures. Utilizing an easy, reproducible, and cost-effective test to measure ORP may provide a more targeted, reliable approach for administering antioxidant therapy while minimizing the risk of antioxidant overdose. With the increasing awareness and understanding of MOSI as a distinct male infertility diagnosis, future research endeavors can facilitate the development of evidence-based treatments that target its underlying cause

A study of some fundamental physicochemical variables on the morphology of mesoporous silica nanoparticles MCM-41 type

[EN] All variables affecting the morphology of mesoporous silica nanoparticles (MSN) should be carefully analyzed in order to truly tailored design their mesoporous structure according to their final use. Although complete control on MCM-41 synthesis has been already claimed, reproducibility and repeatability of results remain a big issue due to the lack of information reported in literature. Stirring rate, reaction volume, and system configuration (i.e., opened or closed reactor) are three variables that are usually omitted, making the comparison of product characteristics difficult. Specifically, the rate of solvent evaporation is seldom disclosed, and its influence has not been previously analyzed. These variables were systematically studied in this work, and they were proven to have a fundamental impact on final particle morphology. Hence, a high degree of circularity (C = 0.97) and monodispersed particle size distributions were only achieved when a stirring speed of 500 rpm and a reaction scale of 500 mL were used in a partially opened system, for a 2 h reaction at 80 degrees C. Well-shaped spherical mesoporous silica nanoparticles with a diameter of 95 nm, a pore size of 2.8 nm, and a total surface area of 954 m(2) g(-1) were obtained. Final characteristics made this product suitable to be used in biomedicine and nanopharmaceutics, especially for the design of drug delivery systems.This study was funded partially by Departamento Administrativo de Ciencia Tecnología e Innovación–COLCIENCIAS (recipient, Angela A. Beltrán-Osuna); Ministerio de Economía y Competitividad, MINECO, research number MAT2016-76039-C4-1-R (Recipient, José L. Gómez-Ribelles); and Universidad Nacional de Colombia, grant number DIB201010021438 (Recipient, Jairo E. Perilla).Beltrán-Osuna, A.; Gómez Ribelles, JL.; Perilla-Perilla, JE. (2017). A study of some fundamental physicochemical variables on the morphology of mesoporous silica nanoparticles MCM-41 type. Journal of Nanoparticle Research. 19(12):1-14. https://doi.org/10.1007/s11051-017-4077-2S1141912Barrabino A (2011) Synthesis of mesoporous silica particles with control of both pore diameter and particle size. Master Thesis, Chalmers University of Technology, SwedenBastos FS, Lima OA, Filho CR, Fernandes LD (2011) Mesoporous molecular sieve MCM-41 synthesis from fluoride media. Brazilian. J Chem Eng 28:649–658Beck JS, Vartuli JC, Roth WJ, Leonowicz ME, Kresge CT, Schmitt KD, Chu CTW, Olson DH, Sheppard EW, McCullen SB, Higgins JB, Schlenker JL (1992) A new family of mesoporous molecular sieves prepared with liquid crystal templates. J Am Chem Soc 114(27):10834–10843. https://doi.org/10.1021/ja00053a020Beltrán-Osuna AA, Perilla JE (2016) Colloidal and spherical mesoporous silica particles: synthesis and new technologies for delivery applications. J Sol-Gel Sci Technol 77(2):480–496. https://doi.org/10.1007/s10971-015-3874-2Bernardos A, Mondragón L, Aznar E et al (2010) Enzyme-responsive intracellular controlled release using nanometric silica mesoporous supports capped with “saccharides”. ACS Nano 4(11):6353–6368. https://doi.org/10.1021/nn101499dBharti C, Nagaich U, Pal AK, Gulati N (2015) Mesoporous silica nanoparticles in target drug delivery system: a review. Int J Pharm Investig 5(3):124–133. https://doi.org/10.4103/2230-973X.160844Brevet D, Hocine O, Delalande A, Raehm L, Charnay C, Midoux P, Durand JO, Pichon C (2014) Improved gene transfer with histidine-functionalized mesoporous silica nanoparticles. Int J Pharm 471(1-2):197–205. https://doi.org/10.1016/j.ijpharm.2014.05.020Cai Q, Luo Z, Pang W et al (2001) Dilute solution routes to various controllable morphologies of MCM-41 silica with a basic medium. Chem Mater 13(2):258–263. https://doi.org/10.1021/cm990661zChakraborty I, Mascharak PK (2016) Mesoporous silica materials and nanoparticles as carriers for controlled and site-specific delivery of gaseous signaling molecules. Microporous Mesoporous Mater 234:409–419. https://doi.org/10.1016/j.micromeso.2016.07.028Chen L, Zhang Z, Yao X, Chen X, Chen X (2015a) Intracellular pH-operated mechanized mesoporous silica nanoparticles as potential drug carries. Microporous Mesoporous Mater 201:169–175. https://doi.org/10.1016/j.micromeso.2014.09.023Chen X, Yao X, Wang C, Chen L, Chen X (2015b) Mesoporous silica nanoparticles capped with fluorescence-conjugated cyclodextrin for pH-activated controlled drug delivery and imaging. Microporous Mesoporous Mater 217:46–53. https://doi.org/10.1016/j.micromeso.2015.06.012Chen Y, Chen H, Shi J (2013) In vivo bio-safety evaluations and diagnostic / therapeutic applications of chemically designed mesoporous silica nanoparticles. Adv Mater 25(23):3144–3176. https://doi.org/10.1002/adma.201205292Chen Y, Shi X, Han B, Qin H, Li Z, Lu Y, Wang J, Kong Y (2012) The complete control for the nanosize of spherical MCM-41. J Nanosci Nanotechnol 12(9):7239–7249. https://doi.org/10.1166/jnn.2012.6459Cheng Y-J, Zeng X, Cheng D-B, Xu XD, Zhang XZ, Zhuo RX, He F (2016) Functional mesoporous silica nanoparticles (MSNs) for highly controllable drug release and synergistic therapy. Colloids Surfaces B Biointerfaces 145:217–225. https://doi.org/10.1016/j.colsurfb.2016.04.051Crommelin DJA, Florence AT (2013) Towards more effective advanced drug delivery systems. Int J Pharm 454(1):496–511. https://doi.org/10.1016/j.ijpharm.2013.02.020Edler KJ (1997) Synthesis and characterisation of the mesoporous molecular sieve, MCM-41. Doctoral dissertation, The Australian National University, AustraliaGuo Z, Liu X-M, Ma L, Li J, Zhang H, Gao YP, Yuan Y (2013) Effects of particle morphology, pore size and surface coating of mesoporous silica on naproxen dissolution rate enhancement. Colloids Surf B Biointerfaces 101:228–235. https://doi.org/10.1016/j.colsurfb.2012.06.026Han N, Wang Y, Bai J, Liu J, Wang Y, Gao Y, Jiang T, Kang W, Wang S (2016) Facile synthesis of the lipid bilayer coated mesoporous silica nanocomposites and their application in drug delivery. Microporous Mesoporous Mater 219:209–218. https://doi.org/10.1016/j.micromeso.2015.08.006Hu X, Wang Y, Peng B (2014) Chitosan-capped mesoporous silica nanoparticles as pH-responsive nanocarriers for controlled drug release. Chem - An Asian J 9(1):319–327. https://doi.org/10.1002/asia.201301105Huh S, Wiench JW, Yoo J et al (2003) Organic functionalization and morphology control of mesoporous silicas via a co-condensation synthesis method. Chem Mater 15(22):4247–4256. https://doi.org/10.1021/cm0210041Ikari K, Suzuki K, Imai H (2006) Structural control of mesoporous silica nanoparticles in a binary surfactant system. Langmuir 22(2):802–806. https://doi.org/10.1021/la0525527Iliade P, Miletto I, Coluccia S, Berlier G (2012) Functionalization of mesoporous MCM-41 with aminopropyl groups by co-condensation and grafting: a physico-chemical characterization. Res Chem Intermed 38(3-5):785–794. https://doi.org/10.1007/s11164-011-0417-5IUPAC (1985) Reporting physisorption data for gas/solid systems. Pure Appl Chem 57:603–619IUPAC (2014) Compendium of chemical terminology-gold book, 2.3.3. International Union of Pure and Applied ChemistryKhezri K, Roghani-Mamaqani H, Sarsabili M, Sobani M, Mirshafiei-Langari SA (2014) Spherical mesoporous silica nanoparticles/tailor-made polystyrene nanocomposites by in situ reverse atom transfer radical polymerization. Polym Sci Ser B 56(6):909–918. https://doi.org/10.1134/S1560090414660026Kresge CT, Leonowicz ME, Roth WJ, Vartuli JC, Beck JS (1992) Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism. Nature 359(6397):710–712. https://doi.org/10.1038/359710a0Lelong G, Bhattacharyya S, Kline S, Cacciaguerra T, Gonzalez MA, Saboungi ML (2008) Effect of surfactant concentration on the morphology and texture of MCM-41 materials. J Phys Chem C 112(29):10674–10680. https://doi.org/10.1021/jp800898nLv X, Zhang L, Xing F, Lin H (2016) Controlled synthesis of monodispersed mesoporous silica nanoparticles: particle size tuning and formation mechanism investigation. Microporous Mesoporous Mater 225:238–244. https://doi.org/10.1016/j.micromeso.2015.12.024Mamaeva V, Sahlgren C, Lindén M (2013) Mesoporous silica nanoparticles in medicine: recent advances. Adv Drug Deliv Rev 65(5):689–702. https://doi.org/10.1016/j.addr.2012.07.018Manzano M, Aina V, Areán CO, Balas F, Cauda V, Colilla M, Delgado MR, Vallet-Regí M (2008) Studies on MCM-41 mesoporous silica for drug delivery: effect of particle morphology and amine functionalization. Chem Eng J 137(1):30–37. https://doi.org/10.1016/j.cej.2007.07.078Merkus HG (2009) Particle size measurements: fundamentals, practice, quality. Springer Science +Businees Media B.V, The NetherlandsMorishige K, Fujii H, Uga M, Kinukawa D (1997) Capillary critical point of argon, nitrogen, oxygen, ethylene, and carbon dioxide in MCM-41. Langmuir 13(13):3494–3498. https://doi.org/10.1021/la970079ude Padua Oliveira DC, de Barros ALB, Belardi RM et al (2016) Mesoporous silica nanoparticles as a potential vaccine adjuvant against Schistosoma mansoni. J Drug Deliv Sci Technol 35:234–240. https://doi.org/10.1016/j.jddst.2016.07.002Phillips E, Penate-Medina O, Zanzonico PB, Carvajal RD, Mohan P, Ye Y, Humm J, Gonen M, Kalaigian H, Schoder H, Strauss HW, Larson SM, Wiesner U, Bradbury MS (2014) Clinical translation of an ultrasmall inorganic optical-PET imaging nanoparticle probe. Sci Transl Med 6(260):260ra149. https://doi.org/10.1126/scitranslmed.3009524Qu F, Zhu G, Lin H, Zhang W, Sun J, Li S, Qiu S (2006) A controlled release of ibuprofen by systematically tailoring the morphology of mesoporous silica materials. J Solid State Chem 179(7):2027–2035. https://doi.org/10.1016/j.jssc.2006.04.002Rafi AA, Mahkam M, Davaran S, Hamishehkar H (2016) A smart pH-responsive nano-carrier as a drug delivery system: a hybrid system comprised of mesoporous nanosilica MCM-41 (as a nano-container) & a pH-sensitive polymer (as smart reversible gatekeepers): preparation, characterization and in vitro releas. Eur J Pharm Sci 93:64–73. https://doi.org/10.1016/j.ejps.2016.08.005Rouquerol J, Rouquerol F, Llewellyn P, et al (2014) Adsorption by powders and porous solids: principles, methodology and applications. Elsevier Ltd.Selvam P, Bhatia SK, Sonwane CG (2001) Recent advances in processing and characterization of periodic mesoporous MCM-41 silicate molecular sieves. Ind Eng Chem Res 40(15):3237–3261. https://doi.org/10.1021/ie0010666Shi YT, Cheng HY, Geng Y, Nan HM, Chen W, Cai Q, Chen BH, Sun XD, Yao YW, Li HD (2010) The size-controllable synthesis of nanometer-sized mesoporous silica in extremely dilute surfactant solution. Mater Chem Phys 120(1):193–198. https://doi.org/10.1016/j.matchemphys.2009.10.045Shibata H, Chiba Y, Kineri T, Matsumoto M, Nishio K (2010) The effect of heat treatment on the interplanar spacing of the mesostructure during the synthesis of mesoporous MCM-41 silica. Colloids Surfaces A Physicochem Eng Asp 358(1-3):1–5. https://doi.org/10.1016/j.colsurfa.2009.12.020Slowing II, Vivero-Escoto JL, Wu C-W, Lin VSY (2008) Mesoporous silica nanoparticles as controlled release drug delivery and gene transfection carriers. Adv Drug Deliv Rev 60(11):1278–1288. https://doi.org/10.1016/j.addr.2008.03.012Sun R, Wang W, Wen Y, Zhang X (2015) Recent advance on mesoporous silica nanoparticles-based controlled release system: intelligent switches open up. Nano 5(4):2019–2053. https://doi.org/10.3390/nano5042019U.S. Department of Health & Human Services (2015) Cancer Nanotechnology PlanUkmar T, Maver U, Planinšek O, Kaučič V, Gaberšček M, Godec A (2011) Understanding controlled drug release from mesoporous silicates: theory and experiment. J Control Release 155(3):409–417. https://doi.org/10.1016/j.jconrel.2011.06.038Vallet-Regi M, Arcos Navarrete D (2016) Nanoceramics in clinical use, 1st edn. The Royal Society of Chemistry, CambridgeVallet-Regi M, Rámila A, Del Real RP, Pérez-Pariente J (2001) A new property of MCM-41: drug delivery system. Chem Mater 13(2):308–311. https://doi.org/10.1021/cm0011559Varga N, Benko M, Sebok D et al (2015) Mesoporous silica core-shell composite functionalized with polyelectrolytes for drug delivery. Microporous Mesoporous Mater 213:134–141. https://doi.org/10.1016/j.micromeso.2015.02.008Wang Y, Zhao Q, Han N, Bai L, Li J, Liu J, Che E, Hu L, Zhang Q, Jiang T, Wang S (2015) Mesoporous silica nanoparticles in drug delivery and biomedical applications. Nanomed Nanotechnol Biol Med 11(2):313–327. https://doi.org/10.1016/j.nano.2014.09.014Wanyika H, Gatebe E, Kioni P et al (2011) Synthesis and characterization of ordered mesoporous silica nanoparticles with tunable physical properties by varying molar composition of reagents. African J Pharm Pharmacol 5(21):2402–2410. https://doi.org/10.5897/AJPP11.592Wu SH, Mou CY, Lin HP (2013) Synthesis of mesoporous silica nanoparticles. Chem Soc Rev 42(9):3862–3875. https://doi.org/10.1039/c3cs35405aXu X, Lü S, Gao C, Wang X, Bai X, Gao N, Liu M (2015a) Facile preparation of pH-sensitive and self-fluorescent mesoporous silica nanoparticles modified with PAMAM dendrimers for label-free imaging and drug delivery. Chem Eng J 266:171–178. https://doi.org/10.1016/j.cej.2014.12.075Xu X, Lü S, Gao C, Wang X, Bai X, Duan H, Gao N, Feng C, Liu M (2015b) Polymeric micelle-coated mesop orous silica nanoparticle for enhanced fluorescent imaging and pH-responsive drug delivery. Chem Eng J 279:851–860. https://doi.org/10.1016/j.cej.2015.05.085Xu X, Lü S, Gao C, Feng C, Wu C, Bai X, Gao N, Wang Z, Liu M (2016) Self-fluorescent and stimuli-responsive mesoporous silica nanoparticles using a double-role curcumin gatekeeper for drug delivery. Chem Eng J 300:185–192. https://doi.org/10.1016/j.cej.2016.04.087Yang Y, Yu C (2015) Advances in silica based nanoparticles for targeted cancer therapy. Nanomedicine nanotechnology. Biol Med 12(2):317–332. https://doi.org/10.1016/j.nano.2015.10.018Zhang H, Tong C, Sha J, Liu B, Lü C (2015) Fluorescent mesoporous silica nanoparticles functionalized graphene oxide: a facile FRET-based ratiometric probe for Hg2+. Sensors Actuators B Chem 206:181–189. https://doi.org/10.1016/j.snb.2014.09.051Zhou C, Yan C, Zhao J, Wang H, Zhou Q, Luo W (2016) Rapid synthesis of morphology-controlled mesoporous silica nanoparticles from silica fume. J Taiwan Inst Chem Eng 62:307–312. https://doi.org/10.1016/j.jtice.2016.01.03