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PubMed2005

Spectrophotometric determination of tranexamic acid in pharmaceutical bulk and dosage forms.

In this study, a simple, fast, accurate and sensitive spectrophotometric method has been developed for the determination of tranexamic acid in bulk and pharmaceutical preparations. The method is based on the reaction of ninhydrin with the primary amino group of tranexamic acid in the basic medium at pH 8.0. The reaction produces a bluish-purple color which absorbs maximally at 565 nm. Beer's law was obeyed in the range of 3-40 microg ml(-1) with molar absorptivity of 5.093 x 10(3) L mol(-1) cm(-1). The effects of various factors such as temperature, heating time, concentration of reagent, color stability and interferences were investigated to optimize the procedure. The results have been validated analytically and statistically. The proposed method has been applied for the determination of tranexamic acid in bulk and pharmaceutical preparations with good results.

Dosage Forms↗
PubMed1997

Anti-bacterial action of onion (Allium cepa L.) extracts against oral pathogenic bacteria.

In this study, the focus was on the antibacterial activity of onions. This study researched the activities of onion extracts on Streptococcus mutans and Streptococcus sobrinus, the main causal bacteria for dental caries, and Porphyromonas gingivalis and Prevotella intermedia, considered to be the main causal bacteria of adult periodontitis. The results showed that the onion extracts possess an effect on all test bacterial strains (S.mutans JC-2, S. sobrinus OMZ176, P. gingivalis ATCC 33277 and P. intermedia ATCC 25611), and the effects were bactericidal against cultured and resting bacterial cells. The activity of the onion extracts was stable even after 48 hours in the culture medium. This result suggests that no decomposition or volatility of onion extracts occurred in the culture medium. The antibacterial activity of onion extracts was not markedly influenced by cysteine (10 mM) treatment. However, activity significantly decreased with alkali treatment. Grated onion left to stand at 37 degrees C for 48 hours did not show antibacterial activity. Also, activity of steam treated (100 degrees C, 10 min.) onion was not observed. Using avicel plate by thin layer chromatography with the solvent of n-butanol:acetic acid:water (3:3:1), the main component of the substance (the substance which develops color with ninhydrin) was observed at an Rf value of about 0.9.

1-Butanol↗
PubMed2000

Evaluation of 1,2-indanedione and 5,6-dimethoxy-1,2-indanedione for the detection of latent fingerprints on porous surfaces.

The ability of 1,2-indanedione and 5,6-dimethoxy-1,2-indanedione to detect latent prints on porous surfaces, as compared to DFO and ninhydrin, has been evaluated. Comparisons of prints developed under various conditions determined the optimum development conditions for the new reagents. The indanediones tested were found to have lower detection limits for glycine. The carrier solvent used was found to affect the quality of the prints developed. In Arklone, the new reagents developed prints that displayed superior luminescence to those developed with DFO. In HFE 7100, 1,2-indanedione and 5,6-dimethoxy-1,2-indanedione gave superior luminescence to DFO after zinc salt treatment and cooling with liquid nitrogen, both of which improve the luminescence of prints developed with 1,2-indanediones. 1,2-Indanediones could offer less expensive but effective alternatives to DFO. With further optimization, the new reagents may supersede DFO as the method of choice for the detection of latent fingerprints on porous surfaces.

Dermatoglyphics↗
PubMed2003

Forensic applications of chemical imaging: latent fingerprint detection using visible absorption and luminescence.

Chemical imaging technology is a rapid examination technique that combines molecular spectroscopy and digital imaging, providing information on morphology, composition, structure, and concentration of a material. Among many other applications, chemical imaging offers an array of novel analytical testing methods, which limits sample preparation and provides high-quality imaging data essential in the detection of latent fingerprints. Luminescence chemical imaging and visible absorbance chemical imaging have been successfully applied to ninhydrin, DFO, cyanoacrylate, and luminescent dye-treated latent fingerprints, demonstrating the potential of this technology to aid forensic investigations. In addition, visible absorption chemical imaging has been applied successfully to visualize untreated latent fingerprints.

Aza Compounds↗
PubMedDate not supplied

1H-NMR spectroscopy of urinary components of SHN mice in the course of spontaneous mammary tumourigenesis.

Proton nuclear magnetic resonance (1H-NMR) spectroscopy of urine was studied before and after the development of spontaneous mammary tumours in SHN mice. Urinary allantoin and lactic acid levels declined from 2 weeks before mammary tumour appearance and increased with the tumour growth after its appearance. The level of component at 3.4 ppm, which reacted with Ninhydrin and was possibly assigned to taurine, continued to decline beginning 2 weeks before tumour appearance. No considerable changes were observed in urinary levels of creatine and creatinine before and after tumour development, however, these components as well as allantoin or lactic acid had positive correlations with mammary tumour size. A negative correlation was observed between the level of 3.4 ppm component and tumour size. Surgical removal of tumours resulted in an apparent decline in urinary levels of allantoin and lactic acid. At all stages, urinary allantoin level was approximately 4 times as high as the levels of lactic acid and 3.4 ppm component. All results suggest that urinary allantoin would be a good indicator for the development of spontaneous mammary tumours of mice.

Allantoin↗
PubMed2005

Genipin, a novel fingerprint reagent with colorimetric and fluorogenic activity, part II: optimization, scope and limitations.

Genipin, a hydrolytic product of geniposide extracted from gardenia fruit, was thoroughly studied as a potential fingerprint reagent, and optimal conditions for fingerprint development have been determined. Latent fingerprints on paper items that have been treated with a non-ink running formulation containing 0.17% of the reagent, showed up as both colored and fluorescent images. On brown wrapping paper and on papers with highly luminescent backgrounds, genipin developed more visible and clearer prints than did classical reagents such as ninhydrin or DFO. Another potential advantage of genipin is that it is totally harmless and an environmentally friendly reagent.

Aza Compounds↗
PubMed1990

Determination of reduced disulfide groups in monoclonal antibodies.

Reduction of disulfide bonds to sulfhydryl groups for direct radiolabeling of antibodies for immunoscintigraphic and therapeutic applications continues to be of considerable interest. Sensitive spectrophotometric methods have been evaluated that will enable investigators to determine submicrogram quantities of cysteine units produced, for the assurance of controlled reduction. One method, which generates a cysteine-ninhydrin complex (520 nm), has a molar extinction coefficient of 30 250 and can determine 0.04 micrograms/ml cysteine units with an absorbance of 0.01. The method has been applied to determine the quantity of cysteine groups produced by the reduction of an immunoglobin G antibody with five different reducing agents in normal to five times the previously determined optimal molar ratios. The quantities of cysteine units produced from the controlled reduction from 240 micrograms immunoglobin G ranged from 0.073 +/- 0.01 to 1.07 +/- 0.04 micrograms, which were merely 0.54 +/- 0.08% to 7.9 +/- 0.28% of the total available disulfide groups in the protein.

Antibodies, Monoclonal↗
PubMed1988

Inhibition of glucokinase by alloxan through interaction with SH groups in the sugar-binding site of the enzyme.

Alloxan is known to inhibit pancreatic B cell and liver glucokinase and glucose protects the enzyme against inhibition. The dithiol 1,4-dithiothreitol (1,4-DTT) protected against and reversed the inhibition of glucokinase by alloxan. An investigation into the structure-activity relationship using a variety of different dithiols demonstrated that the ability of the dithiols to protect against and to reverse the inhibition of glucokinase by alloxan was dependent on the spacing between the SH (thiol) groups of the various dithiols. Only 1,3-dimercaptopropane, 1,4-dimercaptobutane, 1,4-dithioerythritol, and 1,4-DTT, with intermediate spacing between the SH groups, reversed the inhibition of glucokinase induced by alloxan. Dithiols with two vicinal SH groups such as 1,2-dimercaptoethane and 2,3-dimercaptopropanol (BAL) were ineffective in the same way as dithiols with more widely spaced SH groups such as 1,5-dimercaptopentane and 1,6-dimercaptohexane. Except for 1,6-dimercaptohexane, all dithiols also protected glucokinase against the inhibition of alloxan. The monothiol cysteine, but not glutathione, a tripeptide monothiol, also protected glucokinase against alloxan inhibition but both were unable to reverse the inhibition. Like alloxan, other dithiol reagents such as ninhydrin, N-ethylmaleimide, and maleimide inhibited glucokinase. Glucose and 1,4-DTT protected glucokinase against this inhibition. 1,4-DTT partially reversed this inhibition. It is concluded, therefore, that the mechanism of inhibition of glucokinase by alloxan is a reaction of alloxan with two adjacent SH groups in the depth of the sugar-binding site of the glucokinase, with formation of a disulfide bond and concomitant inactivation of the enzyme. Because glucokinase can couple changes in the blood glucose concentration to changes in the glycolytic flux rate and corresponding changes in the rate of insulin secretion, it may function as a glucose signal recognition enzyme in the pancreatic B cell. This mechanism of interaction of alloxan with glucokinase may thereby provide an explanation for the ability of alloxan to inhibit glucose-induced insulin secretion.

Alloxan↗
PubMed1988

[Amino acid analysis of proteins and physiological fluids in a single system of sodium-citrate buffer].

Programmes for automatic analysis of protein and peptide hydrolysates and physiological fluids in a single system of sodium citrate buffers are proposed. Retention time values of 59 ninhydrin-positive substances, including nonprotein amino acids, amino sugars (muramic acid, glucosamine, galactosamine, mannosamine and fucosamine) and corresponding aminopolyols, as well as three cysteine derivatives, viz. cysteic acid, S-carboxymethylcysteine and S-2-(pyridyl-4)ethylcysteine, have been determined. Several examples illustrate an increase of the resolution simply by change of the temperature programme of the column and (or) elution time.

Amino Acids↗
PubMed1987

Quality control for amino acid visualization reagents.

A method is described that quantitatively evaluates development conditions and reactivity of amino acid visualization reagents. Ninhydrin was the primary reagent used in this study. The method consists of spotting a serial dilution of amino acids in a numbered grid on paper. Examples of the variability of development as a result of atmospheric conditions are illustrated.

Amino Acids↗
PubMed1986

Urea removal by means of direct binding.

The availability of more efficient means for the removal of metabolic waste products, especially urea, from dialysates, body fluids or the gastrointestinal tract, is a key to new and simpler ways of treatment of renal failure patients. A research program of Organon Teknika in cooperation with AKZO Chemie has resulted in development of a new sorbent in which the active element is the ninhydrin entity. This product irreversibly binds urea under mild conditions without formation of side products. Also creatinine is bound. The sorbent proves to be non-toxic, non-pyrogenic, stable, insoluble and resistant against acid and sterilization procedures. In combination with amongst others a sorbent for phosphate and potassium developed earlier, the urea sorbent can be applied in dialysate regeneration. In vitro experiments show that for dialyses of four hours duration less than one kg of urea sorbent can be sufficient. Also other applications, e.g., oral use are mentioned.

Adsorption↗
PubMedDate not supplied

[Urinary excretion of toxic peptides in patients with thermal burns].

A fraction of toxic ninhydrin-positive substances was isolated from urine of healthy persons and of the patients with acute burn toxemia using a multi-step technique, which involved ion exchange chromatography on Dowex resins, gel filtration on Sephadex G-15 and ultrafiltration on Diaflo UM-0.5. The daily excretion of the substances was about 4-fold higher in the patients as compared with healthy persons. The fraction contained basic peptides with molecular masses of 500-2,000 daltons. The total toxicity of these peptide was higher by an order of magnitude in the patients with burns as compared with healthy persons.

Animals↗
PubMed1980

Anticonvulsive activity of indenoimidazolidinones and related heterocyclic compounds in mice.

A series of substituted cyclic ureides and related compounds, one of them a thio analog, were synthesized by condensing ninhydrin with urea, thiourea, dimethylurea or other aromatic or bifunctional agents. When tested against seizures induced in mice by the chemoconvulsant Metrazol or against audiogenic seizures, four compounds decreased either the incidence or the severity of convulsive manifestations and protected from mortality in seizures. The effective compounds were not toxic at the administered level (150 mg/kg) and produced few observable sedative effects.

Acoustic Stimulation↗
PubMed1994

Photometric estimation of cadaverine oxidation by copper amine oxidase.

A simple method for the photometric estimation of 1-piperideine, produced by the action of copper amino oxidases on cadaverine, is described. A discussion on the formation of 1-piperideine from lysine in acidic medium is also reported, together with some observations on the nature of acid 1-piperideine-ninhydrin condensation product.

Amine Oxidase (Copper-Containing)↗
PubMed1977

Comparison of the finger wrinkling test results to established sensory tests in peripheral nerve injury.

The phenomenon that denervated skin does not wrinkle or shrivel like normal palmar skin after soaking in water was investigated. Forty-one patients with complete or partial peripheral nerve lacerations or traumatic nerve compressions were given a battery of tests to evaluate sensory and motor function. The results from patients' wrinkle tests were compared with the findings from their two-point discrimination and ninhydrin sweat tests. Twenty four patients with recent complete peripheral nerve injuries demonstrated an absence of finger wrinkling, two-point discrimination, and sweating over the cutaneous distribution of the damaged nerve. Nine patients with partial nerve lacerations demonstrated varied results depending upon the amount and location of the nerve injury. Eight patients with nerve compressions continued to wrinkle and sweat even when two-point discrimination was decreased or absent. These findings indicate that only in patients with a recent complete peripheral nerve lesion does an absence of wrinkling always correspond with a loss of other sensory modalities. The presence of wrinkling in a patient with a nerve compression does not correlate with the patient's sensory modalities.

Adult↗
PubMed1997

Amino acid determination in biological fluids by automated ion-exchange chromatography: performance of Hitachi L-8500A.

The Hitachi L-8500A is a newly available apparatus for amino acid (AA) analysis that allows automatic on-line mixing of the ninhydrin reagent. The within-run precision (human plasma pools at three different concentrations) showed CVs < 3.8% except for the lowest concentration of citrulline (4.4%), Tyr (4.5%), and alpha-aminobutyric acid (7.6%), and for the intermediate concentration of Asp (8.7%). Between-run precision (CV) was < 3.1% for 17 AAs and < 8.0% for 24 of 25 AAs (CV Asp = 12.0%). For retention times, within-run precision was < 0.4% and between-run precision < 1.8%. Excellent relations were found between the results from the Hitachi L-8500A and the widely used Beckman 6300 analyzer (0.929 < or = r < or = 0.999). The detection was still linear at 5 mumol/L except for Pro and hydroxyproline (20 mumol/L). The upper limit was at least 2500 mumol/L for 13 AAs and at least 1000 mumol/L for 27 of 29 AAs (anserine = 500, Val = 600 mumol/L). Values from 100 human plasma samples agreed with previously published data. We conclude that the results obtained with the Hitachi L-8500A are satisfactory when compared with those of other AA analyzers utilizing the same method. Furthermore, the Hitachi L-8500A displays several advantages including programming flexibility, microsample capacity, low noise plotting, ammonia filtering, and manual repacking of the analytical column.

Amino Acids↗
PubMedDate not supplied

TLC resolution of enantiomers of amino acids and dansyl derivatives using (1R,3R,5R)-2-azabicyclo[3,3,0]octan-3-carboxylic acid as impregnating reagent.

The enantiomeric resolution of certain amino acids and some of their dansyl derivatives was achieved on thin silica gel plates impregnated with (1R,3R,5R)- 2-Azabicyclo[3,3,0]octan-3-carboxylic acid, which is an industrial waste material, and a proline analogue non proteinogenic alpha-amino acid. Different combination of 0.5 M NaCl-MeCN were found to be successful in resolving dansyl-DL-amino acids; addition of methanol was required in some cases. Spots were visualised using a fixed wavelength (254 nm) ultraviolet chamber. Resolution of DL-amino acids was successful in different combinations of MeCN-MeOH-H2O and detection was made with ninhydrin (0.2% in acetone).

Amino Acids↗
PubMed1999

Bioassay-directed isolation of oxytocic principles from the methanol extract of Monechma ciliatum.

The hot methanol extract (HME) of Monechma ciliatum which has been reported to have potent oxytocic activity was purified by fractionation in an attempt to isolate the oxytocic principle. Thin layer analysis indicated that the oxytocic fraction was very polar. A positive reaction with ninhydrin-spray suggested that it is an amino acid/protein. Repeated column chromatography (CC) on silica gel followed by sephadex LH-20 column, accompanied by bioassay of the fractions on the rat isolated uterus enabled partial isolation of the oxytocic principle (P3) to be achieved. Although the exact structure of P3 could not be identified from the present study, various spectral analyses suggest that it is a small peptide made up of tyrosine, leucine and a third component which is probably serine. It is interesting to note that the parent compound, oxytocin, is also a peptide with tyrosine and leucine in its structure.

Animals↗