A novel, extreme low-cost poly (Erythrosine) modified pencil graphite electrode for determination of Adrenaline.

A simple, novel, and less cost yellow (Erythrosine) modified pencil graphite electrode (Po-ERY/MGPE) was successfully fabricated via electropolymerization method using cyclic voltammetric techniques. The fabricated Po-ERY/MGPE opted as a sensor for the detection of Adrenaline (ADR) in 0.2 M PBS (7.4 pH). This reported senor displayed excellent electrocatalytic activity, increased sensitivity, high stability, superior electron transfer kinetics in the oxidation of ADR once relative to BGPE. The significance of pH, scan rate, and impact of concentration was assessed at the sensor. As per the pH and scan rate study, redox routes carry the same number of electrons and protons, and electro-oxidation of ADR was adsorption controlled respectively. The LOD of ADR was found to be 0.499 µM. The DPV data indicate that there is a significant peak divergence among ADR and uric acid (UA) which could make it easier to determine them alone and simultaneously on the sensor. The described method has been employed for the determination of ADR in injection sample. Good recovery values indicate the efficacy and applicability of the sensor in detecting ADR.

Preclinical study of a cost-effective photodynamic therapy protocol for treating oral candidoses.

Photodynamic therapy (PDT) is a promising treatment for oral candidoses. Its use as an alternative to antifungals prevents several adverse effects, including microbial resistance. However, most PDT protocols do not employ devices and consumables commonly available in dental practice, thus influencing treatment affordability. This study aimed to determine the efficacy of a PDT method based on light curing units' blue LEDs combined to a plaque-disclosing composition (5% erythrosine) against C. albicans in culture and in a murine model of oral candidosis. Standard and resistant fungal strains were tested in vitro in planktonic and biofilm forms. PDT (pre-irradiation time periods: 30 and 60 s; irradiation time: 3 min) was compared to control conditions without light and/or erythrosine. Mice with induced oral candidosis (n = 40) randomly received PDT or similar control conditions with subsequent C. albicans count. These mice underwent histological analysis, as well as 12 healthy mice submitted to experimental treatments. PDT completely inactivated C. albicans planktonic cells and biofilm. Control conditions presented minor differences (ANOVA, p < 0.05), with mean values ranging from 5.2 to 6.8 log10 (UFC/mL). Infected mice presented no significant difference in C. albicans counts consequent to treatments (ANOVA, p = 0.721), although the PDT protocol was able to enhance the inflammatory infiltrate in healthy mice. It can be concluded that the tested PDT protocol can inactivate C. albicans but still needs further investigation in order to achieve efficacy and safety.

A new screening method for proteinuria using Erythrosin B and an automated analyzer--rapid, sensitive and inexpensive determination.

BACKGROUND: In spite of the urgent necessity for a screening test of urinary protein for the early diagnosis of kidney diseases, a rapid, accurate and cost-effective method for their detection has yet to be developed. METHODS: A solution containing a buffer agent (pH 2.3) and surfactants and a solution of Erythrosin B are added to a urine sample. After letting the mixture stand for 5 min at 37°C, the dye-bound protein is measured by a spectrophotometer at 546 nm using a Hitachi 7170S automated analyzer. RESULTS: The calibration curve was linear with human serum albumin concentration in the range of 2.4-200 mg/l. The detection limit, 2.4 mg/l was superior to conventional dye-binding methods by one order of magnitude and comparable to the turbidimetric immunoassay (TIA). Spot urine samples from 70 patients who showed (-) or (±) in the dip-stick screening test for proteinuria and 79 healthy volunteers were analyzed. There was an excellent correlation (r=0.978, n=149) between the results given by the proposed method and those by the TIA. CONCLUSIONS: This method provides a viable alternative to the conventional immunoassay-based methods for urinary protein measurement, and will be useful in the diagnosis of early stage kidney disease.

Adsorptive removal of Erythrosine dye onto activated low cost de-oiled mustard.

The present paper is aimed to investigate and develop cheap adsorption methods for colour removal from wastewater using waste material de-oiled mustard as adsorbent. De-oiled mustard, a biosorbent, was successfully utilized for removing a water-soluble xanthene dye, Erythrosine from wastewater. Kinetic studies of adsorption of Erythrosine at de-oiled mustard were carried out at 30 degrees C, using aqueous solutions with 5 x 10(-5)M concentration of Erythrosine. The adsorption process followed a pseudo-first order model. The equilibrium process can be well described by both Freundlich and Langmuir models, at 30, 40 and 50 degrees C. Free energy of adsorption (DeltaG degrees ), enthalpy (DeltaH degrees ), and entropy (DeltaS degrees ) changes were calculated to predict the nature of adsorption. The estimated values for DeltaG degrees were -12.81 x 10(3) and -12.57 x 10(3) over activated carbon and activated de-oiled mustard at 203 K (30 degrees C), indicate toward a spontaneous process. The positive value for DeltaH degrees indicates that the adsorption of Erythrosine dye to de-oiled mustard is an endothermic process.

Assessment of the influence of energy under-reporting on intake estimates of four food additives.

Under-reporting has been identified as an important source of uncertainty in food chemical exposure assessments. The objective of the present study was to assess the influence of under-reporting on food additive intake estimates. Dietary survey data were derived from the North-South Ireland Food Consumption Survey (2001). Data from the Republic of Ireland (n = 958) were used. Energy under-reporters were identified using a ratio of energy intakes to estimated basal metabolic rate. First, food categories (n = 26) included in an assessment of exposure of four food additives were created and patterns of food intakes (i.e. likelihood of consumption, frequency of consumption and reported portion size) between acceptable and under-reporters compared. Second, for each food additive, deterministic intake estimates for the total sample (i.e. acceptable and under-reporters), under-reporters and acceptable reporters were calculated and compared. Differential reporting of the majority of food categories between acceptable and under-reporters was recorded. Under-reporters were less likely to record the consumption of a given food and more likely to under-report the frequency of consumption and portion size compared with acceptable reporters. Food additive intake estimates amongst acceptable reporters were higher than corresponding intake estimates amongst the total sample of reporters and amongst under-reporters. With the exception of one food additive (erythrosine), ratios of upper percentile additive intakes amongst acceptable reporters to corresponding intake estimates amongst the total sample of reporters did not exceed 1.06 when results were expressed as total population or consumer-only intakes. Findings illustrated that energy under-reporting does not materially influence estimates of food additive exposure based on the four food additives studied. However, a number of situations were identified where the under-reporting might exert a more significant impact on resulting exposure estimates.

Subgingival debridement of root surfaces with a micro-brush: macroscopic and ultrastructural assessment.

AIM: The aim of this study was to assess the use of a micro-brush to remove plaque deposits from subgingival, periodontally involved root surfaces in vivo. METHODS: 30 periodontally involved teeth requiring extraction for periodontal or prosthetic reasons in 26 adult patients were utilised. For inclusion, teeth had to display at least 30% bone loss radiographically. Following the establishment of local anaesthesia, grooves were cut on the proximal root surface adjacent to the gingival margin at the line angles. For each tooth, 1 proximal root surface was rubbed with the micro-brush for 2 min to the depth of the pocket whilst the other root surface acted as an undebrided control. The teeth were then extracted, rinsed in 0.85% NaCl, stained with 2% erythrosine solution and photographed. The amount of erythrosine staining on each subgingival, periodontally involved root surface was assessed by tracing the areas of stain on a colour photograph and scanning the tracings into a computerised image tracing program. RESULTS: Results were expressed as the % of the periodontally involved root-surface area that exhibited staining. Stained areas were further examined with the scanning electron microscope (SEM). The undebrided root surfaces each displayed 100% staining. The debrided surfaces (with probing pocket depths of 4-10 mm) displayed mean staining of 16.1% (SD +/-7.1%) of the proximal surface area. SEM assessment showed that undebrided root surfaces were covered with thick deposits of bacteria. On debrided surfaces, stain-free areas were free of plaque whilst areas of faint staining exhibited either no plaque, calculus deposits or scanty, isolated islands of bacteria. Bacteria had been partially removed from the surface of calculus in some areas. CONCLUSIONS: The findings indicate that subgingival debridement with a micro-brush is effective in removing plaque deposits from periodontally involved root surfaces.

Colorimetric micromethod for protein determination with erythrosin B.

Reaction of erythrosin B with proteins results in a stable, highly colored chromophore with an absorbance maximum at 545 nm. This is the basis for a new quantitative determination method of proteins in solution. The assay can be performed at room temperature, but is faster and more sensitive at 90-95 degrees C. The erythrosin assay is characterized by (i) stable dye-protein color, (ii) high sensitivity (2-14 micrograms/ml protein), (iii) short reaction time (1.5-2 min at 90-95 degrees C), (iv) good reproducibility, (v) limited interference by common reagents, and (vi) low protein-to-protein variability. Thus, the erythrosin assay can be useful for routine analytical purposes and may overcome some of the limitations of other currently employed assays.

Photochemically induced spinal cord ischaemia in rats: assessment of blood flow by laser Doppler flowmetry.

A photochemical technique was used to create central nervous system ischaemia in rats. Changes in blood flow in the spinal cord were assessed by laser Doppler flowmetry. The Th11 spinal cord segment was irradiated by an argon ion laser after intravenous injection of an organic dye, erythrosin B, to rats with or without a laminectomy. In the group of laminectomized rats, laser irradiation for 5 s did not influence cord blood flow, but 10 s irradiation caused a 25% decrease of blood flow, which normalized within 20 min. Decreases of 50 and 80% in spinal cord blood flow were noted after 20 s and after 1 min of laser irradiation, respectively, with no recovery observed after 20 min. In the group of rats without a laminectomy, 1 min of laser irradiation caused approximately a 25% decrease of spinal cord blood flow, which gradually recovered within 12 min, whereas 5 min of laser irradiation caused a more severe reduction of spinal cord blood flow (45%) with some recovery was observed 30 min later. We could thus confirm that the interaction between a photosensitizing dye and laser irradiation reduced the regional spinal cord blood flow and the extent of this effect could be modified by varying the duration of laser irradiation. The present results therefore provide further support for using this photochemical technique to create animal models of central nervous system ischaemia.

An assessment of the in vivo clastogenicity of erythrosine.

In an investigation of the in vivo clastogenic potential of the food colouring erythrosine (ER), male B6C3F1 mice were treated by ip injection at doses of 50, 100 and 200 mg/kg, repeated 24 hr apart. Signs of toxicity were observed at the highest dose of ER administered. The three cytogenetic endpoints analysed were sister chromatid exchanges (SCEs) in peripheral blood lymphocytes (PBLs), micronuclei in bone marrow polychromatic erythrocytes (PCEs), and micronuclei in peripheral blood reticulocytes (PBRs). SCE frequencies in PBLs were 4.13, 4.58, 4.33 and 4.60 SCE/cell at 0, 50, 100 and 200 mg ER/kg, respectively. At the same doses, the frequencies of micronucleated PCEs were 3.5, 3.2, 2.0 and 2.5/1000 PCEs. Micronuclei in PBRs ranged from 1.2 to 3.6 and from 1.4 to 3.0/1000 PBRs in control and treated mice, respectively. These results indicate that ER is inactive as a clastogen in mouse blood and marrow cells. This result supports the hypothesis of a non-genotoxic mechanism for ER carcinogenicity.

Photographic assessment of the antiplaque properties of sanguinarine and chlorhexidine.

The purpose of this study was to assess the effect of rinsing and topical application of sanguinarine on labial surface plaque accumulation, compared with topically applied water, and compared with rinsing with chlorhexidine, while refraining from all oral hygiene measures for 5 days. Color photographs of the disclosed plaque were taken at the end of each phase of treatment and blindly traced using an Apple II micro-computer graphic tablet digitizer. The plaque score for each tooth was calculated by dividing the computer reading of the labial plaque surface area by the total labial surface area of the tooth. Topically applied sanguinarine showed better plaque reduction than mouthrinsing with sanguinarine. There was a significant reduction in plaque accumulation after rinsing with chlorhexidine compared with topically applied sanguinarine, water, and mouthrinsing with sanguinarine. The results of this study indicate that chlorhexidine is a more superior antiplaque agent than sanguinarine. The use of an Apple II micro-computer graphic tablet digitizer provided a valuable method for accurate plaque assessments.