Multivitamin Preparations Research Articles

Spectrophotometric determination of cobalt with nitrosochromotropic acid

A sensitive spectrophotometric method for the determination of trace amounts of cobalt based on the complex formation with nitrosochromotropic acid in ammoniacal medium is described. After its extraction as thiocyanate complex into isobutylmethyl ketone, cobalt is stripped into nitrosochromotropic acid in ammonia buffer. The method has been applied to the determination of cobalt in mild steel, ferrous alloys and multivitamin preparations.

Identification of vitamins A, D and E by particle beam liquid chromatography-mass spectrometry

Particle beam (PB) high performance liquid chromatography (HPLC)-mass spectrometry (MS) has been studied to investigate its suitability for the analysis of fat-soluble vitamins, as an example of thermally labile substances. The PB LC-MS system has been used to detect and identify vitamins A, D and E in foods and multi-vitamin preparations. The qualitative performance of the PB interface has been evaluated by an examination of the working parameters. A rapid elution of the vitamins was obtained on a C8 reversed-phase column using an aqueous methanol mobile phase. Analyses have been carried out using both, electron (EI) and chemical (CI) ionization. Positive and negative-ion CI spectra of the compounds are discussed. When PB-MS conditions are optimized, the detection limits for the fat-soluble vitamins tested have been typically in the 0.6–25 ng range when using the selected-ion monitoring technique.

HPLC determination of inositol in multivitamin preparation containing large amounts of sugars.

糖分析に用いられるアクリルアミド修飾カラム及び示差屈折検出器を用いたHPLCにより多量の糖類や各種成分を含む医薬品ドリンク剤中に配合されているイノシトールを,前処理せずに直接定量する目的で検討を行った.その結果,アセトン・水系移動相を用い,カラムを2本直結し分離能を高めることにより,イノシトールとその他の共存成分が良好に分離する条件を設定した.この条件を用いてモデル処方製剤中のイノシトールの定量を行ったところ,簡便に精度よく定量できた.又,市販の各種ドリンク剤の分析に応用したところ,各製剤とも精度よく表示量どおりの定量結果が得られた.本法は誘導体化などの前処理なしで定量でき,他の分析方法に比べ操作が非常に簡便である.又,この条件では通常用いられる各種糖類及び甘味剤の影響も受けず,多量の糖を含むドリンク剤中のイノシトール定量法としてはん用性が高い手法である.

Vitamin A and E Status in Elderly Subjects and the Effect of Long-term Administration of a Multivitamin Preparation on Status

Vitamin A and E Status in Elderly Subjects and the Effect of Long-term Administration of a Multivitamin Preparation on Status

Vitamin A and E status in very low birth weight infants: Development of an improved parenteral delivery system

Plasma vitamin A and E levels were inadequate in very low birth weight infants receiving a continuous infusion of a parenteral multivitamin preparation, 1.5 ml/kg per day, in dextrose-amino acid solution. A new delivery system using 2 ml/kg per day, infused for 6 hours from the first day of life, avoided loss during infusion and significantly improved plasma vitamin A and E levels during the first 28 days of life in very low birth weight infants. (J P EDIATR 1995;126:128-31)

Thiamin and Riboflavin Status in Long-term Hospitalized Elderly Patients. : Effect of Long-term Daily Administration of A Multivitamin Preparation

Thiamin and Riboflavin Status in Long-term Hospitalized Elderly Patients. : Effect of Long-term Daily Administration of A Multivitamin Preparation

Stability of ascorbic acid in a standard total parenteral nutrition mixture

We investigated the stability of ascorbic acid (AA) and the sum of AA plus dehydroascorbic acid (TAA) in a total parenteral nutrition (TPN) mixture that contained 1000 ml Vamin 14, 1000 ml glucose 30%, 500 ml Intralipid 20%, potassium phosphate, a multivitamin preparation (Cernevit) and trace elements. We used a spectrophotometer to measure AA and TAA. AA decreased from 42.2 (±0.9) μg/ml to 6.8 (±0.2) μg/ml in 7 days. Over the same time the concentration of TAA decreased from 42.2 (±0.5) μg/ml to 35.9 (±0.6) μg/ml, i.e. 63.3 (±1.2)% of the original concentration. When the solution was stored in glass bottles and saturated with nitrogen or when trace elements were omitted, the concentration decreased by only 25.2 (±0.2)% and 23.8 (±1.6)% respectively over 7 days. The influence of oxygen, lipids, trace elements and underfilling the bag was also investigated. We conclude that it is acceptable to prepare these bags in advance and to store them for 7 days at 2–4°C.

The effect of vitamin and mineral supplementation on esophageal cytology: Results from the linxian dysplasia trial

The population of Linxian in China has one of the world's highest rates for esophageal/gastric cardia cancer, as well as documented nutritional deficiencies. To determine whether dietary supplementation with a multi-vitamin multi-mineral preparation could reduce the risk of esophageal cancer and favorably influence precursor lesions, 3,318 individuals age 40-69 with cytologically determined grade 1 or grade 2 esophageal dysplasia were randomly assigned to receive either an active multi-vitamin multi-mineral supplement or a placebo. Pills were distributed at monthly visits and incident cancers or deaths were recorded. At 30 and 72 months subsequent to randomization all living participants without a known incident cancer were asked to undergo repeat cytological examination of their esophagus. Based on these procedures participants were classified as having no dysplasia, dysplasia grade 1, dysplasia grade 2 or near cancer dysplasia. Diagnoses of cancer were based on the cytology findings plus available histologic, radiologic and clinical materials. At the end of the study there was little overall difference in cumulative risk of esophageal cancer between those receiving vitamin/mineral supplementation and those receiving placebo. There was, however, a significant increase in reversion to non-dysplastic cytology among the group receiving the active treatment. The odds of not having any dysplasia at the two post-randomization screens was 1.23 times higher in the active treatment group than in the placebo group. Within each treatment group higher categories of dysplasia were associated with higher rates of cancer.

Relation between Lens Opacities and Vitamin and Mineral Supplement Use

The authors evaluated the cross-sectional and longitudinal relations between lens opacities and intake of vitamins and minerals in supplements. Type and quantity of vitamins and minerals taken currently and 10 years before interview were obtained in a population-based sample of persons in the Nutritional Factors in Eye Disease Study (n = 2152). In persons without diabetes, regular use of multivitamin preparations 10 years in the past was associated with decreased risk for nuclear sclerosis (odds ratio [OR], 0.6; 95% confidence interval [CI], 0.5, 0.8) and increased the risk for cortical opacities (OR, 1.6; CI, 1.1, 2.2). In persons with diabetes, past multivitamin use was not associated with nuclear sclerosis (OR, 1.1; CI, 0.4,2.7) but with decreased risk for cortical opacities (OR, 0.1; CI, 0.0, 0.9). Cross-sectional associations with current intake of supplements were weaker, but in the same direction. Multivitamin use was not cross-sectionally or longitudinally related to posterior subcapsular cataract in persons with or without diabetes. Use of vitamin supplements is longitudinally associated with nuclear and cortical opacities. However, the direction of the association is influenced by the type of opacity and diabetes status.

Spectrophotometric determination of mixtures of iron(III) and manganese(II) by complexation with 3-indolylacetohydroxamic acid and principal component regression multivariate calibration

The use of principal component regression (PCR) for the multicomponent analysis of complex mixtures offers considerable advantages over conventional multiple linear regression in ultraviolet–visible spectrophotometry. PCR provides a sensitive and accurate technique for the analysis of complex mixtures with severely overlapping spectra. A method for the simultaneous determination of Fe3+ and Mn2+ is described based on the measurement of the absorbance of the complexes formed by both ions with 3-indolylacetohydroxamic acid. The complexes were extracted with a solution of methyltrioctylammonium chloride in toluene. The application of the PCR multivariate calibration method allowed the resolution of the overlapping of the spectra of the respective Fe3+ and Mn2+ complexes with the hydroxamic acid derivative. The method was applied satisfactorily to the determination of Fe3+ and Mn2+ in several multivitamin preparations.

Serum vitamin K concentration in pediatric patients receiving total parenteral nutrition.

The only multivitamin preparation for total parenteral nutrition currently available in the United States that contains vitamin K is the pediatric formulation MVI-Pediatric. The recommended dose provides 200 micrograms of vitamin K1 per day to term infants and children up to 11 years old. This dose is well above the recommended dietary allowance of approximately 1 microgram/kg per day, but the losses of vitamin K during administration are unknown. We evaluated the stability of vitamin K1 in a standard total parenteral nutrition infusion and found that an average 72.7 +/- 4.9% of the original vitamin K1 was present after 24 hours. By using high-performance liquid chromatography with electrochemical reduction and fluorescence detection, we obtained the serum vitamin K1 concentrations in 11 pediatric patients receiving total parenteral nutrition with MVI-Pediatric (Rorer Pharmaceuticals, Fort Washington, PA) supplementation and in control children. The serum vitamin K1 concentration (19.3 +/- 12.2 ng/mL) in patients receiving MVI-Pediatric is significantly higher than that in control children 1.9 +/- 1.5 ng/mL (p < .001). Current practice results in excessive levels of vitamin K in pediatric patients.

Periconceptional Folic Acid Exposure and Risk of Occurrent Neural Tube Defects

Objectives. —A recent controlled trial has established that use of a 4-mg folic acid supplement before and during early pregnancy reduces the risk of recurrent neural tube defects (NTDs) by 72%. The present study was designed to determine whether folic acid also reduces the risk of first (occurrent) NTDs. Design. —Case-control study. Setting. —Tertiary and birth hospitals in metropolitan areas of Boston, Mass, Philadelphia, Pa, and Toronto, Ontario. Participants. —Mothers of 436 occurrent cases with NTDs and mothers of 2615 controls with other major malformations. Main Outcome Measures. —The prevalence of use of multivitamins containing folic acid was compared between mothers of cases and controls. Results. —The mothers of 17% of cases and 3% of controls reported knowledge of the folic acid—NTD hypothesis and were excluded from further analysis. For daily use of multivitamins containing folic acid in the periconceptional period (28 days before through 28 days after the last menstrual period), the relative risk (RR) (and 95% confidence interval) was 0.4 (0.2 to 0.6). The most commonly used dose of folic acid was 0.4 mg, and the RR estimate was 0.3 (95% confidence interval, 0.1 to 0.6). For dietary folate, there was a dose-related decline in risk according to the quintile of intake ( P for trend=.02). Conclusion. —These findings suggest that daily periconceptional intake of 0.4 mg of folic acid (the dose most commonly contained in over-the-counter multivitamin preparations) reduces the risk of occurrent NTDs by approximately 60%. A relatively high dietary intake of folate may also reduce the risk. ( JAMA . 1993;269:1257-1261)

Periconceptional Folic Acid Exposure and Risk of Occurrent Neural Tube Defects

A recent controlled trial has established that use of a 4-mg folic acid supplement before and during early pregnancy reduces the risk of recurrent neural tube defects (NTDs) by 72%. The present study was designed to determine whether folic acid also reduces the risk of first (occurrent) NTDs. Case-control study. Tertiary and birth hospitals in metropolitan areas of Boston, Mass, Philadelphia, Pa, and Toronto, Ontario. Mothers of 436 occurrent cases with NTDs and mothers of 2615 controls with other major malformations. The prevalence of use of multivitamins containing folic acid was compared between mothers of cases and controls. The mothers of 17% of cases and 3% of controls reported knowledge of the folic acid-NTD hypothesis and were excluded from further analysis. For daily use of a multivitamins containing folic acid in the periconceptional period (28 days before through 28 days after the last menstrual period), the relative risk (RR) (and 95% confidence interval) was 0.4 (0.2 to 0.6). The most commonly used dose of folic acid was 0.4 mg, and the RR estimate was 0.3 (95% confidence interval, 0.1 to 0.6). For dietary folate, there was a dose-related decline in risk according to the quintile of intake (P for trend = .02). These findings suggest that daily periconceptional intake of 0.4 mg of folic acid (the dose most commonly contained in over-the-counter multivitamin preparations) reduces the risk of occurrent NTDs by approximately 60%. A relatively high dietary intake of folate may also reduce the risk.

Simultaneous adsorptive stripping voltammetric determination of riboflavin and folic acid in multivitamin preparations

The adsorptive stripping voltammetric behaviour of folic acid and riboflavin was studied at a hanging mercury drop electrode by phase-selective a.c. voltammetry. In 0.1 M sodium acetate buffer (pH 5.0) a cathodic scan gave peaks at −0.29 and −0.55 V vs. Ag/AgCl for riboflavin and folic acid, respectively. The adsorptive stripping response was evaluated with respect to concentration dependence and preconcentration time. Both compounds can be simultaneous determined with a relative standard deviation of 1.4% at 5 × 10−8 M riboflavin and 0.74% at 10−8 M folic acid. The method compared favourably with liquid chromatography with UV detection and was succesfully applied to the simultaneous determination of both compounds in multivitamin preparations. The average contents of riboflavin and folic acid were found to be 15.19 mg ± 2.1% and 1.8 mg ± 2.6%, respectively.

Hypersensitivity Reactions Associated with Parenteral Nutrition: Case Report and Review of the Literature

To report a case of hypersensitivity reaction to total parenteral nutrition (TPN) and to review the available literature on this rare adverse effect. The reaction occurred in a 52-year-old woman with pancreatic carcinoma who received intravenous metronidazole, tobramycin, vancomycin, ranitidine, morphine, TPN, and lipid emulsion postoperatively. Within 30 minutes of starting the TPN and lipid emulsion, the patient complained of dyspnea and pruritus. She began hyperventilating and was hypoxic. The reaction resolved after discontinuation of the TPN and lipid emulsion. The reaction recurred when lipid-free TPN was initiated on two subsequent occasions, and resolved spontaneously following the discontinuation of the lipid-free TPN. The antibiotics, ranitidine, and morphine therapy were continued with no further adverse effects and the patient was discharged on postoperative day 17. Case reports in the literature on TPN-related hypersensitivity reactions were reviewed. It was speculated that the multivitamin preparation (MVI) may have been the causative agent in our patient; however, this was not confirmed by MVI-free TPN administration or by epicutaneous allergy testing. Hypersensitivity reactions to TPN can be managed by withholding the TPN and treating with antihistamines if needed until the reaction resolves. Identification, possibly by epicutaneous allergy testing, and removal of the offending agent(s) from the TPN is necessary if TPN therapy must be restarted.

Characterization of the complexation of fluoroquinolone antimicrobials with metal ions by nuclear magnetic resonance spectroscopy.

The complexation of the fluoroquinolone antimicrobials is important because it has been implicated in reduced oral bioavailability and reduced antimicrobial activity when the drugs are co-administered with antacids or multi-vitamin preparations containing iron. The complexation of two model compounds, lomefloxacin and norflaxacin was studied using NMR. With aluminum ions, exchange between free and bound drug molecules was slow on the NMR time-scale. Two complexes, proposed to have stoichiometries of 2:1 and 3:1 (drug:metal) based on peak widths and variable temperature studies, were observed. The crystal structure of lomefloxacin, which shows intermolecular self association previously reported to be crucial to the drug's mode of action, is also reported. Because the metal ion complexes could not be crystallized, the crystal structure of uncomplexed lomefloxacin together with the NMR data on the aluminum complexes were used in the molecular modelling of the lomefloxacin-aluminum complexes.

Flavin adenine dinucleotide levels in erythrocytes of very low birthweight infants under vitamin supplementation.

Despite the potential dangers of over- and undersupplementation with riboflavin (vitamin B2), little is known about status, requirements and metabolism of this vitamin in very low birthweight (VLBW) infants. As reported here, it is possible to calculate the intraerythrocytic concentration of free flavin adenine dinucleotide (FAD), the predominant coenzyme form of riboflavin, on the basis of the erythrocyte glutathione reductase activation coefficient (EGRAC). This parameter was determined in 9 VLBW infants (median of birthweight 634 g, median of gestational age 24 weeks + 3 days) at intervals over a period of 6 weeks. All infants received riboflavin supplementation, either in milk (average intake: 175 micrograms/kg/day) and a multivitamin preparation (200 micrograms/day) or via total parenteral nutrition (TPN; 720 micrograms/kg/day). The average EGRAC was 1.07 (1.00-1.24) during enteral nutrition and 1.05 (1.00-1.18) during TPN. These values correspond to free FAD levels of 757 and 1,060 nM, which is 4 to 5 times higher than in cord blood or in breast-fed infants. EGRAC values between 1.15 and 1.35, representing free intracellular FAD levels of 350-150 nM, should be adequate in VLBW infants in order to minimize the hazards of flavin-induced radical reactions.

Spectrophotometric study of the complexation equilibria of iron(III) with 3-hydroxypicolinic acid and determination of iron in pharmaceutical preparations.

The complexation equilibria of iron(III) with 3-hydroxypicolinic acid (hypa) have been studied spectrophotometrically in 40% (v/v) ethanol-water medium at 25 degrees C and an ionic strength of 0.1 M NaClO4. The equilibria occurring in solution were established and the basic characteristics of the complexes formed were determined. The spectral study of the reaction solutions containing equimolar concentrations or an excess of one component in the pH range 1.5 to 10.5 gave the evidence for the formation of [FeLH]2+, [FeL]+ and [FeL2]- complex species, depending upon the pH of the medium (LH2 symbolising the molecular form of hypa). The possible complex transitions that occur in solution were demonstrated using graphical and logarithmic analysis of the absorbance-pH graphs. A simple, rapid, sensitive and selective method for spectrophotometric determination of trace levels of iron(III) was proposed based on the formation of Fe(hypa)2 complex at pH 5.5 (lambda = 440 nm, epsilon = 1.5 x 10(4) dm3 mol-1 cm-1). The interference of a large number of foreign ions was investigated. The method has been applied successfully to the analysis of multivitamin and mineral preparations containing iron.

Vitamin A and E Status in Elderly Subjects and the Effect of Single Administration of a Multivitamin Preparation on the Status

Vitamin A and E Status in Elderly Subjects and the Effect of Single Administration of a Multivitamin Preparation on the Status

Thiamin and Riboflavin Status in Elderly : Effect of Single Administration of A Multivitamin Preparation

Thiamin and Riboflavin Status in Elderly : Effect of Single Administration of A Multivitamin Preparation