Spectrophotometric Measurements Research Articles

Smartphone-based colorimetric sensor application for measuring biochemical material concentration

In this paper, colorimetric analysis for biochemical samples has been realized, by developing an easy-to-use smartphone colorimetric sensing android application that can measure the molar concentration of the biochemical liquid analyte. The designed application can be used for on-site testing and measurement. We examined three different biochemical materials with the application after preparation with five different concentrations and testing in laboratory settings, namely glucose, triglycerides, and urea. Our results showed that for glucose triglycerides, and urea the absorbance and transmittance regression coefficient (R2) for the colorimetric sensing application were 0.9825, and 0.9899; 0.9405 and 0.9502; 0.9431 and 0.8597, respectively. While for the spectrophotometer measurement the (R2) values were 0.9973 @560 nm and 0.9793 @600 nm; 0.952 @620 nm and 0.9364 @410 nm; 0.9948 @570 nm and 0.9827 @530 nm, respectively. The novelty of our study lies in the accurate prediction of multiple biochemical materials concentrations in various lightning effects, reducing the measurement time in an easy-to-use portable environment without the need for internet access, also tackling various issues that arise in the traditional measurements like power consumption, heating, and calibration. The ability to convey multiple tasks, prediction of concentration, measurement of both absorbance and transmittance, with error estimation charts and (R2) values reporting within the colorimetric sensing application as far as our knowledge there has not been any application that can provide all the capabilities of our application.

Hydrothermal synthesis of CuO and CeO2/CuO nanostructures: spectroscopic and temperature dependent electrical properties

In this study, CuO and CeO2/CuO nanostructures were successfully synthesized via a hydrothermal route. The structure, morphology, composition and optical properties of these nanostructures have been studied using various techniques. X-ray diffraction (XRD) analysis showed the formation of monoclinic crystalline phase of CuO with a decrease in the crystallinity of the samples as the Ce content increased. Scanning electron microscopy (SEM) acquired images showing that increased Ce incorporation induces transformation of morphology from spherical to rod-like nanostructures. Energy-dispersive X-ray spectroscopy (EDS) mapping showed that Ce was homogeneously distributed onto the CuO matrix. UV/Vis/NIR spectrophotometer measurements depicted a blue shift in the bandgap from 2.0 to 3.5 eV for 0%-6% Ce and then 3.2 eV for 8% Ce. Brunauer Emmett Teller (BET) analysis revealed enhanced porosity with the incorporation of cerium. Raman spectroscopy results confirmed the presence of the $${A}_{g}$$ (296 cm−1), $${B}_{g}$$ (346 cm−1) and $${B}_{g}$$ (631 cm−1) modes belonging to CuO. The F2g Raman active mode observed at 454 cm−1 belongs to CeO2. Fourier transform infra-red (FTIR) measurements showed stretching vibrations of Cu–O. The CeO2/CuO samples exhibited enhanced temperature-controlled Dc conductivity with the 4% Ce sample showing the lowest activation energy, lowest Tmax (peak value of (dσ/dT)) and consequently the maximum conductivity peaking at a temperature of 503 K. The nature of conductivity was elucidated on the basis of the carrier hopping model.

Extraction of optical properties from a turbid medium using fiber probe for spectral and spatial diffuse reflectance measurement

Diffuse reflectance technique is popular in the study of tissue physiology through the change in optical properties in a noninvasive manner. Diffuse reflected light intensity is commonly collected either from a single distance with spectral measurement or from a single wavelength with different spatial distances. Improving existing systems is necessary in order to obtain information from greater depths and in smaller volumes. In this paper, we propose a fast and compact fiber probe-based diffuse reflectance method for combining the spectral measurements in the range of 400–950 nm and spatial information up to 1.33 mm from the illumination source. First, we chose the most appropriate analysis model for the proposed distances between the fiber probe and tested it on solid phantoms with varying scattering and absorption components. The measurements are compared to the scattering coefficients according to Mie theory and the absorption according to spectrophotometer measurements. Next, we measured two-layer phantoms with constant scattering and absorption contrast in different layer thicknesses. We extracted the penetration depth from the measured effective absorption coefficient. In the near-IR, we were able to detect the absorption coefficient of the bottom phantom layer behind a top layer of up to 5 mm. We achieved a maximum penetration depth of 5.7 mm for 5 mm top layer thickness at 900 nm. Our fiber probe diffuse reflectance system can be used in the near future for skin lesion detection in clinical studies.

Hematite reconstruction of Late Triassic hydroclimate over the Colorado Plateau

Hematite is the most abundant surficial iron oxide on Earth resulting from near-surface processes that make it important for addressing numerous geologic problems. While red beds have proved to be excellent paleomagnetic recorders, the early diagenetic origin of hematite in these units is often questioned. Here, we validate pigmentary hematite ("pigmentite") as a proxy indicator for the Late Triassic environment and its penecontemporaneous origin by analyzing spectrophotometric measurements of a 14.5-My-long red bed sequence in scientific drill core CPCP-PFNP13-1A of the Chinle Formation, Arizona. Pigmentite concentrations in the red beds track the evolving pattern of the Late Triassic monsoon and indicate a long-term rise in aridity beginning at ∼215 Ma followed by increased oscillatory climate change at ∼213 Ma. These monsoonal changes are attributed to the northward drift of the Colorado Plateau as part of Laurentia into the arid subtropics during a time of fluctuating CO2 Our results refine the record of the Late Triassic monsoon and indicate significant changes in rainfall proximal to the Adamanian-Revueltian biotic transition that thus may have contributed to apparent faunal and floral events at 216 to 213 Ma.

Dye-free spectrophotometric measurement of nucleic acid-to-protein ratio for cell-selective extracellular vesicle discrimination

Extracellular vesicles (EVs) can represent a novel source of disease biomarkers, and are under intensive study for their clinical potential. Most EV-based cancer diagnostic studies have focused on establishing EV assays that detect increased expression of a single cancer-associated marker or marker signatures based on multiplex detection of these biomarkers. EV biomarker readouts can be obscured by high background signal leading to false positives, and may markedly differ between analyses due to variation in sample purity during EV isolation. This can obstruct the comparisons among studies and lead to conflicting conclusions. This work reports that the nucleic acid to protein UV absorption ratio of an EV is a cell-specific EV characteristic. This EV collective attribute can be measured at low-cost to discriminate EVs derived from malignant and non-malignant cells rather than employing single markers that may be cancer- or subtype-specific. Our work also highlighted the application for accessing purity in EV preparations irrelevant to EV yield. It can be employed to distinguish from patients with and without malignant disease upon analysis of EVs isolated from their serum samples.

Visual validation of the appearance of chromatic objects rendered from spectrophotometric measurements.

We validate a physically based and spectral rendering framework with improved color reproduction. With a recently developed model, we take into account both the colorimetric specifications of the rendering display as well as the spectral and angular characteristics of lighting and also the spectral reflectance of the objects. Therefore, it should provide much better color reproduction than those based on the common standard red, green, blue (sRGB) color space. In addition, it allows real-time rendering on modest hardware and displays. We evaluated the color reproduction of the new rendering framework by psychophysical tests using spectrophotometric measurements of 30 chromatic paint samples. They were rendered on an iPad display, as viewed inside the Byko-spectra effect light booth. We asked 16 observers to evaluate the color match by directly comparing the rendered samples with the physical samples, using two different psychophysical assessment methods. The color reproduction was found to be strongly improved with respect to results obtained with default sRGB color encoding space. The average color reproduction match was found to be equivalent to ΔE00=1.6, which is a small but noticeable color difference. In 80% of the visual assessments, the color reproduction was described as being at least as good as between "difference visible but still acceptable" and "difference visible, doubtful match."

A fully automated system with an optical immersion probe (OIP) for high-precision spectrophotometric measurements

A new and fully automated system with the interconnection of an Optical Immersion Probe (OIP) – pH meter – peristaltic pump was used to study the spectral and protolytic properties of carbocyanine the dyes 1,1′,3,3,3′,3′-hexamethylindocarbocyanine chloride (HIC); 1,1′,3,3,3′,3′-hexamethylindodicarbocyanine iodide (HIDC); and 3,3′-diethyloxadicarbocyanine iodide (DODC). This system can measure a large number of experimental points in a short time period. The effect of 32 various organic solvents on the UV-ViS spectra of the dyes was studied. The solvatochromic behaviour of studied dyes was characterized by positive solvatochromism for HIDC and negative solvatochromism for HIC and DODC. Through the application of a large number of experimental points, the protonation and hydrolysis constants of dyes were determined with high precision, where the confidence interval of the рK values is ±(0.001–0.005), compared with a confidence interval of ±(0.04–0.10) for standard procedures. The fully automated system presented is accurate, fast, environmentally friendly and promising for multiple analytical applications.

Massive Integration of Planktonic Cells within a Developing Biofilm.

During biofilm growth, the coexistence of planktonic and sessile cells can lead to dynamic exchanges between the two populations. We have monitored the fate of these populations in glass tube assays, where the Bacillus thuringiensis 407 strain produces a floating pellicle. Time-lapse spectrophotometric measurement methods revealed that the planktonic population grew until the pellicle started to be produced. Thereafter, the planktonic population decreased rapidly down to a value close to zero while the biofilm was in continuous growth, showing no dispersal until 120 h of culture. We found that this decrease was induced by the presence of the pellicle, but did not occur when oxygen availability was limited, suggesting that it was independent of cell death or cell sedimentation and that the entire planktonic population has integrated the biofilm. To follow the distribution of recruited planktonic cells within the pellicle, we tagged planktonic cells with GFP and sessile cells with mCherry. Fluorescence binocular microscopy observations revealed that planktonic cells, injected through a 24-h-aged pellicle, were found only in specific areas of the biofilm, where the density of sessile cells was low, showing that spatial heterogeneity can occur between recruited cells and sessile cells in a monospecies biofilm.

A Wavelength Selection Model Based on Successive Projections Algorithm for pH Detection of Water by VIS-NIR Spectroscopy

A novel pH detection method using VIS-NIR (visible near infrared) spectroscopy for water is introduced in this paper. In order to improve prediction accuracy and calculation speed of pH detection using VIS-NIR spectroscopy, a wavelength selection model of SPA-MLR (successive projections algorithm and multiple linear regression) is proposed. Two experiments (pH measurement experiment by VIS-NIR spectrophotometer and pH measurement experiment by VIS-NIR grating spectrograph) are employed to evaluate the performance of SPA-MLR. At meanwhile, PLS (partial least squares), GA-PLS (genetic algorithm and partial least squares) are introduced to compare with SPA-MLR. The results indicate that, the prediction accuracy and calculation speed of SPA-MLR are all better than that of PLS and GA-PLS. Under the pH measurement experiment using VIS-NIR spectrophotometer, only one wavelength is selected from 351 original wavelengths for calibration, the RMSEP (root mean square errors of prediction) is 0.35, and the model training speed is 2.36s. Under the pH measurement experiment using VIS-NIR grating spectrograph, 3 wavelengths are selected from 2860 original wavelengths for calibration, the RMSEP is 0.50, and the model training speed is 56.45s. For the two experiments, the selected wavelength variables by SPA are distributed mainly in the band of 870 nm to 990 nm.

AI-based hyperspectral and VOCs assessment approach to identify adulterated extra virgin olive oil

Spectral and VOCs data are important to determine the genuineness of the EVOO. The aim of this work is to apply an open-source device for VIS–NIR spectrophotometric measurements and a VOCs analyzer to identify some types of sophistication. 96 samples were analyzed. Samples included pure EVOO compound olive oil pure seed oils and olive oil samples adulterated with 7 different seed oils at different ratios. An artificial intelligence model was applied to identify adulterations from the spectral and VOCs data. The models built on both spectral and VOCs data showed perfect classification of pure EVOO samples with respect to sophisticated ones in both model and test sets. The most important spectral values and VOCs were extracted. Artificial intelligence applicative models aimed not only to identify sophisticated samples but also to understand the most informative spectra and VOCs to prototype specific devices for anti-fraud control.

Morphological and optical properties induced by ultraviolet radiation of a thiadiazole derivative

CThB amorphous thin films were synthesized by thermal evaporation technique. The amorphous structure of thin films was investigated by X-ray diffraction technique (XRD). The surface morphology of CThB thin films were analyzed by atomic force microscopy (AFM). The optical constants such as refractive index, n, the absorption index, k, and the absorption coefficient, α for as-deposited and UV—irradiated thin films were determined by spectrophotometric measurements of transmittance (T) and reflectance (R) at normal light incidence of wavelength in range (200–2500) nm. The absorption spectrum of CThB shows two absorption bands in UV region of spectra ascribed to n → π* orbital molecular transition. The results denote that UV—irradiation has no effect on the type of electron transition. Optical measurement of CThB as—deposited and UV- irradiated thin films showed normal dispersion of refractive index, n at λ > 750 nm and anomalous dispersion at λ < 750 nm. Some of dispersion parameters such as the high-frequency dielectric constant (e∞), the lattice dielectric constant (eL), the dispersion energy (Ed), the oscillator energy (Eo) and ratio of the free charge carrier concentrate to effective mass (N/m*) were calculated. The optical functions as the real (e1), imaginary (e2) parts of the dielectric constant were estimated and their response to UV—irradiation was discussed. The effect of UV—irradiation on optical energy gap $${E}_{g}^{\text{ind}}$$ with respect of exposure time was estimated. The value of the band gap was found to be 2.5 eV. The width of the localized states was found to be 0.3 eV and was increased upon irradiation.

Spectrophotometric color matching for pre-colored fiber blends based on a hybrid of least squares and grid search method

Computer color matching can improve production efficiency and reduce costs in color spun. However, in practice the computer color matching success rate for pre-colored fiber blends has not been good, leading to customers being unsatisfied with the accuracy of the color matching results. Aiming to improve the accuracy, a hybrid of least squares and grid search method has been proposed for spectrophotometric color matching of pre-colored fiber blend based on the improved Kubelka–Munk (K-M) double-constant theory. Two-primary, three-primary, four-primary, and five-primary pre-colored cotton fiber blends were prepared as standard samples to evaluate the color matching accuracy of the proposed method. Compared with the least squares method and the grid search method, the proposed method achieved better color matching effects and greatly shortened the calculation time, respectively. For 42 pre-colored fiber blends, the average color difference between the predicted results obtained by the proposed method, least squares method, and grid search method and the spectrophotometer measurements were respectively 0.29, 0.53, and 0.36 CIE2000 units. The experimental results indicated that the proposed method could predict the formulation of standard samples quickly and effectively, and that it was superior to other methods in providing satisfactory color matching results for the enterprises.

Effect of Sn doping concentration on structural, optical and electrical properties of ZnS/p-Si (111) diodes fabricated by sol-gel dip-coating method

Tin doped zinc sulfide (ZnS:Sn) thin films have been fabricated by sol-gel dip-coating method on glass and p-Si substrates by varying Sn concentration between 0 wt % and 10 wt %. The structural and optical properties of ZnS:Sn thin films have been studied by X-ray diffraction and spectrophotometer measurements. X-ray results show the films grown on glass and p-Si substrate are cubic structure. Optical band gap values found from the transmittance spectra have decreased from 3.58 eV to 3.42 eV with the addition of Sn. The effect of tin concentration on the device performance of ZnS:Sn/p-Si has been investigated through the analysis of the I–V characteristics under dark and illuminated conditions. Diode parameters such as ideality factor n, barrier height Φb, saturation current Io, series resistance value RS have been calculated by means of thermionic emission theory, and Norde method. Photosensitivity PS, photoresponsivity R, and detectivity D values of the diodes have been determined from I–V measurements under 100 mW/cm2 illumination intensity. It has been determined that 3% Sn doped ZnS/p-Si diode showed the best diode and photodiode properties among Sn doped ZnS/p-Si diodes.

SnO2/VO2/SnO2 tri-layer thermochromic films with high luminous transmittance, remarkable solar modulation ability and excellent hydrophobicity grown on glass substrates

The SnO2/VO2/SnO2 (SVS) multilayer films were prepared using pulsed laser deposition and were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, Hall Effect Measurement System, double beam spectrophotometer and contact angle measurements. The results showed that SVS multilayer films with excellent thermochromic properties were obtained by adjusting the preparation temperature of the SnO2 buffer layer and antireflection layer. When the preparation temperature of the SnO2 layer was 320 °C, the phase transition amplitude (ΔR) of the VO2 film reached 354 times and both the phase transition temperature (Tc) and hysteresis loop width (ΔH) could be effectively reduced. Meanwhile, the SVS multilayer film had satisfactory luminous transmittance (50.2%) and solar modulation ability (15.3%), achieving the balance of optical properties. In addition, all the SVS multilayer films exhibited excellent hydrophobicity. Boiling water experiments show that the service life of SVS tri-layer film is twice that of SV bi-layer film. This work suggests that the SVS multilayer films are a good candidate for VO2-based smart windows.

Influence of the deposition temperature on the optical and electrical properties of TiN film by spectroscopic ellipsometry

Abstract Low emission (Low-e) films are widely used in modern architectural glass. In this presentation, spectroscopic ellipsometry (SE) between 1.12 and 2.75 eV (wavelength range: 450–1100 nm) was used to investigate the temperature dependence of dielectric function of TiN films. A Drude-3Lorentz dispersion model was selected and the results show both the real part e 1 and the imaginary part e 2 increase with the deposition temperature increasing. The structure and performance of the obtained TiN samples were characterized by X-ray diffraction, Raman, scanning electron microscope, UV/Visible (UV/VIS) spectrophotometer and Hall measurements. Combining the measured results, it is found that with the deposition temperature increasing, the grain size of TiN film changed from 15.4 nm to 17.4 nm and the surface becomes rougher. The concentrations of titanium and nitrogen vacancies decrease with increasing deposition temperature. A combined Drude-3Lorentz model was used to analyze the dielectric and optical properties of the obtained TiN films. It is found that TiN samples exhibit typical Drude-Lorentz like behavior in the visible and near-infrared (NIR) regions. The results were verified by Hall measurements and UV/VIS measurements. With the deposition temperature increasing, the reflectivity increased in the NIR region and a peak reflectivity of about 93% can be obtained at the wavelength of 1000 nm. With the deposition increasing, the infrared emissivity decreased. The infrared emissivities of the TiN film deposited at 673 K are 0.26 and 0.08 at wavelength of 2.5 μm and 25 μm, respectively, which shows TiN may be a good candidate for low-e film.

ДОСЛІДЖЕННЯ ВАЛІДАЦІЙНИХ ХАРАКТЕРИСТИК МЕТОДИКИ КІЛЬКІСНОГО ВИЗНАЧЕННЯ ПАРАЦЕТАМОЛУ ТА ЙОГО ОСНОВНОЇ ДОМІШКИ В РЕКТАЛЬНИХ СУПОЗИТОРІЯХ

Еxploration of validation characteristicsof the method for the quantitative determination of paracetamol and its main impurity 4-aminophenol in rectal suppositories by spectrophotometry (UV) and high performance liquid chromatography (HPLC). Spectrophotometric measurements were carried out on a UV VIS Lambda 35 spectrophotometer (Perkin Elmer, USA) in cuvettes l = 1 cm. We used a Waters 2695 liquid chromatography with a Waters 2489 UV-detector, as well as a Nucleosil C18 chromatographic column with a size of 250 × 4.6 mm, filled with octadecylsilyl sorbent with a particle size of 10 microns. We used reagents: purified water, which was obtained from the Milli Q plant, manufactured by Millipore Corporation (Germany), sodium hydroxide Sigma-Aldrich, cat. № 06203, sodium 1-butanesulfonate Sigma-Aldrich, cat. № 19022-10G-F; ethanol 96%, methanol Sigma-Aldrich (purity 99.9%), formic acid Sigma-Aldrich, cat. № 33015. Validation characteristics were confirmed as specificity, correctness, precision. The total predicted uncertainty of the analytical method for quantitative determination and the limit of quantitative determination of the main impurity of paracetamol, at which the signal-to-noise ratio is fulfilled, is 10% of the initial concentration of the reference solution (0.5 μg / ml). Confirmed linearity for quantitative determination of paracetamol content in the range of 80 to 120% of the nominal value. Statistical processing of experimental data was carried out; the correlation coefficient of the linear dependence (r) between the entered and found values for the quantitative determination of paracetamol is &gt; 0.990, which indicates the correctness of the method. Methods for the quantitative determination of paracetamol and its main impurity in suppositories have been developed and validated. The method for quantitative determination of paracetamol in suppositories is significantly simpler for routine control of a batch of drugs and is cost-effective compared to the HPLC method. The obtained experimental results indicate that according to the studied validation characteristics, the technique is correct and can be reproduced in other laboratories.

REGULARITIES OF RHENIUM COORDINATION WITH PHENANTHROLINE DONOR LIQAND

Effective methods for the synthesis of a number of complex compounds of rhenium (V) with 1, 10 - phenanthroline have been developed. The composition and structure of the obtained compounds were proved by physico-chemical methods, and their properties were studied by methods of elemental analysis, IR and electron (ESP) spectroscopy and thermogravimetry. Compounds of the composition PhenH2[ReOCl5](I) and PhenH2[ReOBr5](II) were obtained. The [ReOХ3Phen]- (III and IV) (x=Cl, Br) compounds were synthesized by thermal decomposition I and II. It is shown that thermal decompositions I and II proceed with the release of the corresponding hydrogen halide and the rearrangement of the phenanthroline molecule. The transition of phenanthroline from the external sphere (I and II) to the sphere of the ligand environment of rhenium (V) (compounds III and IV) was confirmed by the results of spectrophotometric measurements (IRS, ESP). Keywords: complexes of rhenium, nitrogen containing organic liqands, o-phenantroline.

Octyl 6-O-hexanoyl-β-D-glucopyranosides: Synthesis, PASS, antibacterial, in silico ADMET, and DFT studies

An analytical procedure for the analysis of carotenoids in marine sediments rich in organic matter has been developed. Analysis of these compounds is difficult; the application of methods used by other authors required optimization for the samples studied here. The analytical procedure involved multiple ultrasound-assisted extraction with acetone followed by liquid-liquid extraction (acetone extract:benzene:water - 15:1:10 v/v/v) and HPLC analysis. The influence of column temperature on pigment separation and the quantification method were investigated – a temperature of 5 °C was selected for the Lichrospher 100 RP-18e column. The pigments in the sediment extract were quantified using a method based on HPLC analysis (at 450 nm) and spectrophotometric measurements (at 450 nm), and extinction coefficients were determined for standard solutions at this wavelength. It is very important to use the value of the extinction coefficient appropriate to the wavelength at which the detection of carotenoids was carried out.

Determining the visual Impression of cotton fabrics while Rotating.

In order to identify the light reflectance from cotton fabrics produced from various (spun yarn., ( carded – open end ) ,an attempted measured Light reflectance distribution (CIELAB L*) by using a (GCMS-4 Gonio)-( Spectrophotometric color measurement system) at various Illumination angle (θi) and Viewing angle(θv) with turning point(θw) from ( 0-90)o in both direction .Results clarify the relations between the distribution pattern (L*) with fabrics made from different spun yarn which had an effect for fabrics on visual sense of hymen and indicate more about aesthetics of cotton fabric while rotating. Therefore, the results indicate that L* reflectance measurement for cotton woven fabric shows that lightness values depended on method of spinning but in closer values, weave density also give parameter in light reflectance from woven fabric in weft direction , Illumination angle and Viewing angle also indicate an important parameter for visual sense from fabrics and its related to aesthetic properties. In shorts: (θw) was found to be the most accurate parameter for determining the change of lightness from shiny to dull in visual assessment for cotton woven fabrics.

The Ca2+/ Nucleotide Nanocomplex formulation enhances the pump function of corneal endothelial cells by increasing the activity of Na+/K+ Dependent ATPase

AbstractPurposeNa, K‐ATPase exist in the membrane of the corneal endothelial cell and control the corneal hydration through the pump function. It also plays an important role in preserving the transparency of the cornea. In this study, we investigated the effect of Ca2+/ Nucleotide (NT) nanocomplex (NC) on Na, K‐ATPase and the pump function of the corneal endothelial cells.MethodsBovine corneal endothelial cells were used, and the cells were treated with Ca2+/ Nucleotide (NT) nanocomplex (NC) formulation after various insults. Na, K‐ATPase activity was measured by the spectrophotometric measurement of phosphate released from ATP with the use of ammonium molybdate. The Na, K‐ATPase activity was calculated as the difference in ATPase activity between cells exposed to ouabain and those not exposed. Ussing chamber was used to measure the pump function of endothelial cells. Western blot analysis and immunocytochemistry were performed to measure the expression of Na, K‐ATPase α1 subunit.ResultsThe Ca2+ NT NCs were prepared at a [Ca2+]:[NT]:[bPEI 1.8 kDa] ratio of 0.25 mM:0.5 mM:1.0 mM and these preparations significantly and gradually increased the activity of Na, K‐ATPase in cultured bovine corneal endothelial cells. And these effects were effectively blocked by the PKC inhibitor (protein kinase C). In addition, Ca2+ NT NCs (0.25 mM and 0.5 mM) increased the viability of cells exposed to a low temperature (4°C) for 4 or 8 hours in a serum containing medium (p &lt; 0.05). Western blot analysis indicated that Ca2+ NT NCs formulation significantly decreased the ratio of inactive Na, K‐Atpase α1 subunit (after 12 hours of incubation with 0.5 mM of Ca2+ NT NCs formation). Immunocytochemistry reveals that Ca2+ NT NCs formulation increased the cell surface expression of the Na,K‐ATPase α1 subunit.ConclusionsThis study demonstrates that the Ca2+ NT NC formulation increases the activity of Na, K‐ATPase in the corneal endothelial cells to enhance the pump function. Our results imply a potential therapeutic strategy that the pumping function of the corneal endothelial cells can be improved by the administration of Ca2+ NT NC formulation, which may help to maintain and improve transparency of the cornea.