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1.
Anal Chim Acta ; 1229: 340388, 2022 Oct 09.
Article in English | MEDLINE | ID: mdl-36156238

ABSTRACT

In this work we presented novel strategy for increasing the performance of popular fluorescent probes on the basis of rhodamine-lactam platform. This strategy is based on the incorporation of probe molecules into the light-harvesting nanoparticles to pump modulated optical signal by Förster resonant energy transfer. Using the commercially available Cu2+ probe as a reference chemical, we have developed an efficient approach to significantly improve its sensing performance. Within obtained nanoparticles coumarin-30 nanoantenna absorbs excitation light and pumps incorporated sensing molecules providing bright fluorescence to a small number of emitters, while changing the probe-analyte equilibrium from liquid-liquid to solid-liquid significantly increased the apparent association constant, which together provided a ∼100-fold decrease in the detection limit. The developed nanoprobe allows highly sensitive detection of Cu2+ ions in aqueous media without organic co-solvents usually required for dissolution of the probe, and demonstrate compatibility with inexpensive fluorometers and the ability to detect low concentrations with the naked eye.


Subject(s)
Fluorescent Dyes , Nanoparticles , Coumarins , Fluorescence Resonance Energy Transfer , Fluorescent Dyes/chemistry , Ions/chemistry , Lactams , Nanoparticles/chemistry , Rhodamines/chemistry , Solvents
2.
Nanoscale ; 12(25): 13431-13441, 2020 Jul 02.
Article in English | MEDLINE | ID: mdl-32614002

ABSTRACT

Here, we applied direct laser-induced periodic surface structuring to drive the phase transition of amorphous silicon (a-Si) into nanocrystalline (nc) Si imprinted as regular arrangement of Si nanopillars passivated with a SiO2 layer. By varying the laser beam scanning speed at a fixed pulse energy, we successfully tailored the resulting unique surface morphology of the formed LIPSSs that change from ordered arrangement of conical protrusions to highly uniform surface gratings, where sub-wavelength scale ripples decorate the valleys between near-wavelength scale ridges. Along with the surface morphology, the nc-Si/SiO2 volume ratio can also be controlled via laser processing parameters allowing the tailoring of the optical properties of the produced textured surfaces to achieve anti-reflection performance or partial transmission in the visible spectral range. Diverse hierarchical LIPSSs can be fabricated and replicated over large-scale areas opening a pathway for various applications including optical sensors, nanoscale temperature management, and solar light harvesting. By taking advantage of good wettability, enlarged surface area and remarkable light-trapping characteristics of the produced hierarchical morphologies, we demonstrated the first LIPSS-based surface enhanced fluorescent sensor that allowed the identification of metal cations providing a sub-nM detection limit unachievable by conventional fluorescence measurements in solutions.

3.
Nanoscale ; 11(24): 11634-11641, 2019 Jun 20.
Article in English | MEDLINE | ID: mdl-31173032

ABSTRACT

Active light-emitting all-dielectric nanoantennas recently have demonstrated great potential as highly efficient nanoscale light sources owing to their strong luminescent and Raman responses. However, their large-scale fabrication faces a number of problems related to productivity limits of existing lithography techniques. Thus, high-throughput fabrication strategies allowing in a facile way to tailor of the nanoantenna emission and thermal properties in the process of their fabrication are highly desirable for various applications. Here, we propose a cost-effective approach to large-scale fabrication of Si1-xGex alloyed Mie nanoresonators possessing an enhanced inherent Raman response which can be simply tailored via tuning the Ge concentration. Moreover, by tailoring the relative Ge composition one can gradually change a complex refractive index of the produced Si1-xGex alloy, which affects the ratio between radiative and nonradiative losses in Si1-xGex nanoantennas, which is crucial for optimization of their optical heating efficiency. Composition-tunable Si1-xGex nanoantennas with an optimized size, light-to-heat conversion and Raman response are implemented for non-invasive sensing of 4-aminothiophenol molecules with a temperature feedback modality and high subwavelength spatial resolution. The results are important for advanced multichannel optical sensing, providing information on analyte's composition, analyte-nanoantenna temperature response and spatial position.

4.
Nanoscale ; 10(20): 9780-9787, 2018 May 24.
Article in English | MEDLINE | ID: mdl-29767209

ABSTRACT

All-dielectric resonant micro- and nano-structures made of high-index dielectrics have recently emerged as a promising surface-enhanced Raman scattering (SERS) platform which can complement or potentially replace the metal-based counterparts in routine sensing measurements. These unique structures combine the highly-tunable optical response and high field enhancement with the non-invasiveness, i.e. chemically non-perturbing the analyte, simple chemical modification and recyclability. Meanwhile, commercially competitive fabrication technologies for mass production of such structures are still missing. Here, we attest a chemically inert black silicon (b-Si) substrate consisting of randomly-arranged spiky Mie resonators for a true non-invasive (chemically non-perturbing) SERS identification of the molecular fingerprints at low concentrations. Based on the comparative in situ SERS tracking of the para-aminothiophenol (PATP)-to-4,4'-dimercaptoazobenzene (DMAB) catalytic conversion on the bare and metal-coated b-Si, we justify the applicability of the metal-free b-Si for ultra-sensitive non-invasive SERS detection at a concentration level as low as 10-6 M. We performed supporting finite-difference time-domain (FDTD) calculations to reveal the electromagnetic enhancement provided by an isolated spiky Si resonator in the visible spectral range. Additional comparative SERS studies of the PATP-to-DMAB conversion performed with a chemically active bare black copper oxide (b-CuO) substrate as well as SERS detection of the slow daylight-driven PATP-to-DMAB catalytic conversion in the aqueous methanol solution loaded with colloidal silver nanoparticles (Ag NPs) confirm the non-invasive SERS performance of the all-dielectric crystalline b-Si substrate. A proposed SERS substrate can be fabricated using the easy-to-implement scalable technology of plasma etching amenable on substrate areas over 10 × 10 cm2 making such inexpensive all-dielectric substrates promising for routine SERS applications, where the non-invasiveness is of high importance.

6.
Vestn Ross Akad Med Nauk ; (1): 106-12, 2015.
Article in Russian | MEDLINE | ID: mdl-26027279

ABSTRACT

OBJECTIVE: Our aim was to study the mechanisms of hypoxia development at pregnancy associated with cytomegalovirus infection (CMVI). METHODS: 30 parturient women with CMVI relapse at the 25-28 weeks of pregnancy and their newborns were examined. Cytochrome C, Hsp-70, p53, Bcl-2 and caspase-3 in placenta homogenate were found out with serologic methods, the morphology of erythrocytes with cytophotometry, erythrocytes membrane proteins with disc-electrophoresis method, TBA-active products with V.B. Gavrilov's method, superoxide dismutase activity with spectrophotometry, 2.3-diphosphoglyceric acid (2.3 DPG) with I.S. Luganov's method, erythrocytes membrane microviscosity with fluorimethric method, oxyhemoglobin and methemoglobin with Evelyn and Malloy' method, and erythrocytes deformability with M. T. Lutsenko's method. RESULTS: In blood erythrocytes of CMV-seropositive parturient women there was the decrease of cytoskeleton proteins: α- and ß-spectrine was 1.14 times less, ankyrin was 1.62 times less, band 4. 1 protein was 1.29 times less; there was 1.87 times increase of antigen-binding glycophorin, 1.37 times growth of TBA-active products and 1.35 times drop of superoxide dismutase activity; the deformability index was 9.5 times less, 2.3 DPG was 1.22 times less and oxyhemoglobin was 1.06 times less. In placenta homogenate Bcl-2 was 1.5 times less, Hsp-70 was 2.5 times more, p53 was 6.1 times more, cytochrome C was 1.76 times more, caspase-3 was 3.86 times more. In umbilical cord blood erythrocytes 2.3 DPG was 1.3 times more and oxyhemoglobin was 1.06 times less. CONCLUSION: The obtained data proves that CMVI relapse at 25-28 weeks of pregnancy causes the disorder of morphofunctional state of mother's blood erythrocytes and their ability to oxygenation, the development offetoplacental barrier, the decrease offetus oxygen blood supply and the development of intrauterine hypoxia.


Subject(s)
Cytomegalovirus Infections , Erythrocytes/metabolism , Fetal Hypoxia/etiology , Maternal-Fetal Exchange , Placenta/metabolism , Pregnancy Complications, Infectious , Adult , Caspase 3/blood , Cytochromes c/blood , Cytomegalovirus Infections/metabolism , Cytomegalovirus Infections/physiopathology , Female , Gestational Age , HSP70 Heat-Shock Proteins/blood , Humans , Infant, Newborn , Oxyhemoglobins/analysis , Pregnancy , Pregnancy Complications, Infectious/metabolism , Pregnancy Complications, Infectious/physiopathology , Recurrence , Retrospective Studies , Russia , Tumor Suppressor Protein p53
7.
Anesteziol Reanimatol ; (3): 77-9, 2014.
Article in Russian | MEDLINE | ID: mdl-25306689

ABSTRACT

Early patient's activation is the best method of prophylaxis of many complications of the postoperative period. Patients with obesity are at high risk of developing complications in respiratory system. The following clinical report is about the successful implementation of the shortened postoperative period program in patient with morbid obesity after general desflurane maintained anesthesia and, at the same time, epidural ropivacaine-based anesthesia. Anesthesia lasted for 10 hours. The intraoperative period was well controlled and characterized with stable hemodynamic indexes. On the fourth minute after desflurane intake was terminated and recovery of consciousness and spontaneous breathing of the patient were registered, patient was extubated. This clinical experience and also an information than can be found in the earlier publications allow us to consider a desflurane maintained anesthesia as one of the safest and comfortable methods of anesthesia for patients with a morbid obesity.


Subject(s)
Anesthesia, General/methods , Early Ambulation/methods , Obesity, Morbid/surgery , Adult , Body Mass Index , Humans , Male , Obesity, Morbid/complications , Obesity, Morbid/diagnosis , Postoperative Period , Time Factors , Treatment Outcome
8.
Khirurgiia (Mosk) ; (9): 54-9, 2013.
Article in Russian | MEDLINE | ID: mdl-24077508

ABSTRACT

The efficacy, safety and expediency of various types of the induction anesthesia before the long-lasting major surgery were analyzed. The combination of inhalation of sevoflurane in maximal concentration with phentanil allowed the effective and safe induction and trachea intubation on the 3-4th minute on the background of the nimbex myoplegia. The monoinduction with sevoflurane provides the sufficient analgesia not earlier then after 7-9th minute, which allows the safe intubation at a time. Therefore, the study proved, that the inhalation induction with sevoflurane in various modifications, could be the standard method of inductive anesthesia.


Subject(s)
Anesthesia, Inhalation/adverse effects , Intubation, Intratracheal/methods , Methyl Ethers , Administration, Inhalation , Anesthesia, Inhalation/methods , Anesthetics, Inhalation/administration & dosage , Anesthetics, Inhalation/adverse effects , Anesthetics, Intravenous/administration & dosage , Comparative Effectiveness Research , Fentanyl/administration & dosage , Humans , Methyl Ethers/administration & dosage , Methyl Ethers/adverse effects , Neuromuscular Agents/administration & dosage , Outcome Assessment, Health Care , Sevoflurane
9.
Carbohydr Polym ; 92(1): 769-74, 2013 Jan 30.
Article in English | MEDLINE | ID: mdl-23218366

ABSTRACT

Sensitive layer-by-layer (LbL) coatings for optical detection of gaseous NH(3) and HCl were prepared by self-assembly of oppositely charged polysaccharides (chitosan and λ-carrageenan) followed by doping LbLs with pH-sensitive dyes - bromothymol blue (BTB) and Congo red (CR). It has been shown that CR, being an amphoteric dye, diffuses into LbL films regardless of the charge of the outermost polyelectrolyte layer, and the dye loading increases linearly with the LbL film thickness, whereas BTB diffuses into LbL films only when the outermost layer is positively charged, and linearity between dye loading and film thickness holds only up to 8-12 double layers (DLs) deposited. Formation of dye-doped LbL coatings at the surface of K(+)/Na(+) ion-exchanged glass has allowed fabrication of composite optical waveguide (OWG) gas sensor for detection of ammonia and hydrochloric acid vapors. The response time of BTB-doped composite OWG for ammonia detection was below 1s, and the detection limit was below 1 ppm. CR-doped OWG sensors have shown high sensitivity to HCl vapor but slow relaxation time (up to several hours for 12 DL LbL films).


Subject(s)
Ammonia , Chitosan/chemistry , Gases/isolation & purification , Hydrochloric Acid , Ammonia/chemistry , Ammonia/isolation & purification , Carrageenan/chemistry , Congo Red/chemistry , Hydrochloric Acid/chemistry , Hydrochloric Acid/isolation & purification , Hydrogen-Ion Concentration , Limit of Detection , Phosphatidylethanolamines/chemistry
10.
Anesteziol Reanimatol ; (2): 29-32, 2005.
Article in Russian | MEDLINE | ID: mdl-15938092

ABSTRACT

The purpose of this study was to examine the expediency and efficiency of use of an infusion administration of naropine into the epidural space for intraoperative anesthesia and to develop the optimum procedure for administering this anesthetic during operations on the upper abdomen. Studies were performed in 43 patients operated on for different pancreatic diseases. Anesthesia based on epidural naropine infusion versus ataralgesia was compared. This study indicated that epidural naropine infusion-based anesthesia provides stable hemodynamic parameters and reduces the use of narcotic analgesics by more than twice. Inclusion of prolonged epidural infusion of 0.3% naropine solution into the anesthesiological appliance scheme during this type of operations provides an adequate antinociceptive protection and contributes to the early activation of patients, which prevents the development of postoperative complications.


Subject(s)
Amides/administration & dosage , Anesthesia, Epidural/methods , Pancreatic Diseases/surgery , Anesthesia, General , Female , Humans , Infusions, Parenteral , Male , Middle Aged , Ropivacaine
17.
Kardiologiia ; 24(11): 28-32, 1984 Nov.
Article in Russian | MEDLINE | ID: mdl-6596456

ABSTRACT

The blood lipid levels were collated with the atherosclerotic damage to the coronary bed in 124 patients with coronary heart disease. An increase in the content of total cholesterol and low density lipoprotein cholesterol directly correlated with the degree of the total lesion of the coronary bed. The concentrations of high density cholesterol and very low density cholesterol and the atherogenicity index showed no correlation with the severity of atherosclerotic changes in the coronary arteries. The level of triglycerides in these patients displayed a tendency to increase. In evaluating the severity of coronary heart disease, it is recommended to determine the levels of total cholesterol and low density lipoprotein cholesterol. Changes in the concentration of high density lipoprotein cholesterol are unreliable for assessing the degree of coronary atherosclerosis.


Subject(s)
Coronary Disease/etiology , Lipids/blood , Adult , Cholesterol/blood , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Cholesterol, VLDL , Coronary Disease/blood , Humans , Lipoproteins, VLDL/blood , Male , Middle Aged , Triglycerides/blood
19.
Prikl Biokhim Mikrobiol ; 15(5): 760-3, 1979.
Article in Russian | MEDLINE | ID: mdl-515000

ABSTRACT

Activities of protein-inhibitors of proteases and their correlation with the total content of protein and alkaloids in yellow and white lupine seeds were studied. Yellow lupine seeds showed lowe activities of protein-inhibitors. They also displayed negative correlation between activities of protein-inhibitors and the total content of protein and alkaloids.


Subject(s)
Protease Inhibitors/analysis , Seeds/analysis , Kinetics , Species Specificity
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