Bromocresol Purple Method Research Articles

Spectrophotometric quantification of amitriptyline hydrochloride in pharmaceutical tablets: method development and validation

The development and validation of two uncomplicated, selective, and non-extraction-based visible spectrophotometric methods was carried out for the quantification of a tricyclic antidepressant amitriptyline hydrochloride as pharmaceutical tablets as well as in its pure form. The methods rely on the formation of ion pair complexes between amitriptyline base and two acidic dyes, bromothymol blue and bromocresol purple, which were subsequently measured at 410 and 400 nm, respectively. The developed methods included numerous reaction variables that were examined and improved. Beer's law is applicable under optimal conditions for the bromothymol blue and bromocresol purple methods, respectively, over concentrations from 0.5 to 12.5 μg mL−1 and from 0.5 to 10.0 μg mL−1 amitriptyline hydrochloride. The computed values of molar absorptivity were 1.79 × 104 and 2.32 × 104 L.mol−1.cm−1 for bromothymol blue and bromocresol purple methods, respectively, with Sandell’s sensitivity values of 0.0155 and 0.0119 μg cm−2. Both detection limits and quantification limits were computed and determined to be 0.55 and 1.67 μg mL−1 for bromothymol blue method, and 0.49 and 1.49 μg mL−1 for bromocresol purple method, respectively. The developed methods were successfully applied to estimate the concentration of amitriptyline hydrochloride in bulk form and commercial pills. Therefore, these methods demonstrate promising potential for testing this drug in labs for quality control.Graphical abstractSpectrophotometric quantification of amitriptyline hydrochloride in pharmaceutical tablets: method development and validation

Evaluation of the two-point calibration bromocresol green method, showing reduced deviation from the bromocresol purple method in sera from patients with hypoalbuminemia.

The bromocresol green (BCG) and bromocresol purple (BCP) methods are widely used for albumin measurements in routine testing, but the BCG method is known to react with globulin fractions and to have low specificity for albumin. We evaluated a calibration method using different concentrations of human serum albumin standards (two-point calibration BCG method) with the aim of reducing the effect of globulin fractions on the BCG method in patients with hypoalbuminemia. In the two-point calibration BCG method, two concentrations of standard solutions and their calibration values are set based on the difference in albumin concentrations measured by the BCG method (BCG-HSA method) and the modified BCP (modified BCP-HSA method) calibrated with human serum albumin standard solution (HSA). Albumin concentrations were measured in 136 patient serum samples (healthy group: 52, hypoalbuminemic group: 84) by the two-point calibrated BCG method and compared with those obtained using the modified BCP-HSA method. The mean albumin concentrations obtained using the two-point calibrated BCG and modified BCP-HSA methods were 39.18 ± 3.42g/L and 39.37 ± 3.14g/L (healthy group) and 26.20 ± 6.23g/L and 26.23 ± 5.67g/L (hypoalbuminemia group), respectively. The results of the two-point calibration BCG method were in a close agreement over the entire concentration range tested compared to the modified BCP-HSA method. Based on these results, this calibration method reduces the influence of the globulin fraction on the BCG method. In the hypoalbuminemic group, the calibration method was shown to provide results consistent with the BCP method, which is highly specific for albumin.

Spectrophotometric Methods for Determination of Clopidogrel in Bulk and in Pharmaceutical Formulations

The present article reports three simple, sensitive, and accurate spectrophotometric methods which have been progressed for monitoring of clopidogrel bisulphate (CG) in bulk and in pharmaceutical formulations. The three methods are depended on the production of yellow ion-pair complexes between the investigated drug and bromophenol blue (BPB), bromthymol blue (BTB), and bromocresol purple (BCP) as dyes in a universal buffer of pH range (2.0- 4.0). The chloroform was used for formed complexes extraction and measured at 421 nm, 414 nm, and 409 nm, respectively for the three systems. The best conditions of the reactions were tested and optimized. Beer’s law was obeyed in the concentration ranges 2.0 – 18.0 µg mL-1 with molar absorptivity of 4.4 × 104 , 6.4 × 104 and 6.9 × 104 L mol-1cm-1, for the BPB, BTB and BCP methods, respectively. Sandell’s sensitivity, correlation coefficient, quantification and detection limits are also studied. The investigated methods have been achieved successfully for the determination of the drug in pure form and in pharmaceutical formulations. Interference between common pharmaceutical excipients and additives was disappeared. Statistical comparison of the results with those observed by the HPLC method exhibits excellent agreement and shows no significant difference in terms of accuracy and precision.

Comparison of bromcresol green and bromocresol purple methods for measuring serum albumin levels

Comparison of bromcresol green and bromocresol purple methods for measuring serum albumin levels

Effect of albumin measurement methods on the albumin-bilirubin grade.

Albumin-bilirubin (ALBI) grade is an index of liver function based on total bilirubin (T-BIL) and albumin levels, and its usefulness has been widely reported. This study aimed to investigate the effect of different methods of measuring T-BIL and albumin levels on the ALBI grade in patients with liver disease. In total, 170 patients from our hospital were included in this study. Correlations between T-BIL levels measured using the vanadate oxidation and enzymatic methods were analysed. Similarly, a correlation analysis of albumin levels between the bromocresol green (BCG) and modified bromocresol purple (BCP) methods was performed. Additionally, the ALBI grade was calculated for patients with liver disease, and the differences between each method of albumin measurement were compared. No differences were observed in the measured T-BIL values between the two methods. Contrastingly, the albumin levels of 100 random samples and 70 liver disease patients obtained using the modified BCP method were significantly lower than those measured using the BCG method. The rate of change in the modified ALBI grade between the BCG and BCP methods was 25.7%. Caution should be taken when comparing ALBI grades with those measured by other facilities because the method of albumin measurement can affect the ALBI grade. Standardization of albumin measurement is needed worldwide.

Impact of Albumin Assays in the Diagnosis of Malnutrition in Hemodialysis Patients: A Cohort Study

In hemodialysis (HD) patients, malnutrition should be diagnosed by several assessment tools including a plasma albumin concentration of less than 3.8g/dL or 3.5g/dL using bromocresol green or immunonephelometry (IN), respectively. However, albumin measurement is not yet standardized and two alternative methods are also commonly used in laboratories: bromocresol purple (BCP) and immunoturbidimetry (IT). This study aimed to revisit the hypoalbuminemia thresholds for BCP and IT, in HD patients. Plasma albumin was measured by the four analytical methods during the monthly HD nutritional assessment of 103 prospectively included patients. Significant differences in albumin levels were observed in HD patients depending on the method used. Using BCP or IT with the cut-off at 3.5g/dL (determined for the general population) we obtained 33% and 9.7% of false hypoalbuminemia in comparison to IN (mean bias of -0.4g/dL and -0.065g/dL, respectively). The best hypoalbuminemia threshold for BCP was 3.05g/dL and 3.4g/dL for IT. Twenty percent of HD patients were classified as malnourished when albumin was determined by IN. Similar rates were obtained using the new hypoalbuminemia cut-offs for BCP (18.5%) and IT (19.5%). To avoid nutritional misclassification of HD patients, we should adjust hypoalbuminemia thresholds when BCP or IT methods are used in laboratories.

Choice of assay affects serum albumin measurements in HIV patients: A comparison of bromocresol green and bromocresol purple dye binding methods

Background: Dye-binding assays – bromocresol green (BCG) and bromocresol purple (BCP) –are widely used for serum albumin measurement. Differences between the results reported by these assays can have important clinical implications. There are limited studies elucidating the differences between the results of two assays in HIV patients. We aimed to determine whether the choice of assay affects serum albumin measurements in HIV patients. Materials and Methods: Hundred newly diagnosed HIV patients were included in the study. The subjects were followed up for 6–12 months after initiating ART. Hundred HIV-negative healthy controls matched for age and body mass index were taken as controls. Serum albumin and three acute phase proteins (APPs) (Alpha-1 acid glycoprotein, C-reactive protein, ceruloplasmin) were measured. Serum albumin measurement was done by both BCG and BCP dye binding methods. Paired t-test was used to compare the groups. Results: The concentration of APPs reduces with ART indicating reduced inflammation, and is lowest in the control group. The difference in serum albumin concentrations measured by the two dye binding methods reduces with reduction in APPs. The study further indicates that the BCG method gives higher values of serum albumin as compared to BCP method in the presence of other proteins in the sample. Conclusion: The choice of albumin assay affects the serum albumin assessment of HIV patients. We recommend that the BCP assay be used to measure serum albumin in HIV patients, particularly in patients not on ART.

Is capillary zone electrophoresis a suitable method for estimating serum albumin: A comparison of four methods

BackgroundThe capillary zone electrophoresis method of albumin measurement is frequently used for oncologic and haematologic patients but few data exist about the agreement between the albumin measurements performed by capillary zone electrophoresis and other methods. The aim of this study was to analyse the agreement between human serum albumin measurements by capillary zone electrophoresis and by the nephelometry, bromocresol purple and turbidimetry methods. MethodWe prospectively measured 100 freshly collected non-frozen patient serum samples, by using four different methods: the capillary zone electrophoresis method performed with a CAPILLARYS 2 instrument, the bromocresol purple dye method performed with an Advia XPT analyser, the nephelometric method performed with a BN ProSpec analyser and the turbidimetric method with reagents from DiAgam and performed with the Advia XPT analyser. ResultsA bias towards higher values in the lower range of albumin concentrations was observed with capillary zone electrophoresis compared to immunonephelometry: correlation coefficient r2 = 0.925; slope of 0.86 (0.82–0.89, 95% confidence interval), which is significantly different from 1; and an intercept of 4.94 g/L (3.67–6.16, 95% confidence interval). Similar results were observed when comparing capillary zone electrophoresis to the bromocresol purple and immunoturbidimetry methods. The capillary electrophoresis method overestimated low albumin levels by up to 25% (5 g/L). ConclusionCompared to the nephelometry, turbidimetry and bromocresol purple methods, the capillary zone electrophoresis method tends to overestimate human serum albumin concentrations for levels below 30 g/L. This discrepancy could lead to an overestimation of the nutritional status, an inappropriate scoring of the disease and a delay in nutritional treatment.

Overestimation of Albumin Measured by Bromocresol Green vs Bromocresol Purple Method: Influence of Acute-Phase Globulins.

Usually serum albumin is measured with dye-binding assay as bromocresol green (BCG) and bromocresol purple (BCP) methods. The aim of this paper was to examine the differences in albumin measurements between the Advia2400 BCG method (AlbBCG), Dimension RxL BCP (AlbBCP) and capillary zone electrophoresis (CZE). Albumin concentrations from 165 serum samples were analysed using AlbBCG, AlbBCP and CZE. CZE was employed to estimate different serum protein fractions. Influence of globulins on albumin concentration discrepancies between methods was estimated as well as the impact of the albumin method on aCa concentrations. Medcalc was employed for statistical analysis, setting a value of P < 0.05 as significant. Correlation of AlbBCG and AlbBCP was r = 0.948 (p < 0.0001), but mean difference was large. Bland-Altman plots showed greater bias at lower albumin concentrations. AlbBCG were positively biased versus CZE (3.54 g/L). There was good agreement between CZE and ALbBCP (< 1 g/L). The AlbBCG assay bias shows a good correlation with alpha-1-globulin concentrations (r = 0.758); moderate and weak correlations were observed with CRP (r = 0.729) and alpha-2-globulin (r = 0.585); we found no correlation with beta-globulin (r = 0.120) or gamma-globulin (r = -0.303). Mean aCa based on AlbBCG and AlbBCP methods were 2.34 ± 0.15 mmol/L and 2.46 ± 0.16 mmol/L (p < 0.01), with a mean BCG-BCP difference of -0.12. Albumin results from the BCP and BCG methods may result in unacceptable differences and clinical confusion, especially at lower albumin concentrations. Serum acute phase proteins contribute to overestimating the albumin concentration using AlbBCG.

The importance of serum albumin determination method to classify patients based on nutritional status

The albumin and cholesterol performed in Advia 2400 analyzer using bromocresol green and purple methods to measure albumin. The total lymphocytes performed in Advia 2120. We calculate CONNUT index and classify the patients based on nutritional status. When we classified our patients based on nutritional status (CONNUT), 28% were misclassified, almost in moderate and severe groups. This is very important because this tool generates a multidisciplinary action to the patient. Therefore, in the Clinical Laboratory we have to know the methods we use, the validity of these methods in future tools/index and the management and outcome of the patients.

Extraction-Free Spectrophotometric Assay of Ethionamide in Pharmaceutical Using Two Sulphonphthalein Dyes as Ion-Pair Agents

Two simple, sensitive, selective, rapid and reproducible visible spectrophotometric methods are presented for the determination of ethionamide (ETM) in bulk drug and tablets by employing two sulphonphthalein dyes: bromocresol green (BCG method) and bromocresol purple (BCP) as chromogenic agents. The methods are based on the formation of intensely yellow colored ion-pair complexes upon the reaction of the drug with the cited dyes in chloroform medium. The 1:1 (drug:dye) complexes formed were spectrophotometrically measured at 460 nm without involving the extraction step. Optimization of the experimental conditions is described. Beer’s law is obeyed in the concentration range 1–10 µg ml−1 in both methods, with molar absorptivity values of 1.45 × 104 and 1.68 × 104 l mol−1 cm−1 with BCG method and BCP method, respectively. The calculated limits detection and quantification were 0.02 and 0.07 µg ml−1 with both methods. The suitability of the methods for the quantitative determination of ETM was proved by validation in accordance with the requirements of the ICH guidelines. The coefficients of variation were < 1.65% for intra-day and < 1.90% inter-day analysis, and the accuracy expressed as relative error was ≤ 2%. The methods were applied to the determination of ETM in tablets and the results agreed well with the label claim and those obtained by the reference method. The accuracy of the methods was further ascertained by recovery study via standard-addition procedure. The possible reaction pathway is also discussed.

Reference intervals for the P-Albumin bromocresol purple method

Correct reference intervals are an important part of test results. As establishing own reference intervals is a very expensive task, the NORIP reference intervals are often transferred for use in Nordic laboratories. The NORIP reference interval on P-Albumin was here compared to current results for laboratories using the bromocresol purple (BCP) method for P-Albumin. External quality control reports were used to investigate the change in levels between the BCP and BCG methods on P-Albumin. An algorithm was built for extracting and isolating the laboratory’s healthy subject population. The algorithm was used to extract test results from the laboratory information system. Parametric and non-parametric statistical methods were used to evaluate the P-Albumin test result populations. The indirect method used here clearly shows that the NORIP reference intervals for P-Albumin are not fit for the current bromocresol purple methods. The method was also used to suggest new reference interval limits.

Simple and Sensitive Spectrophotometric Determination of Sildenafil Citrate in Pharmaceutical Formulations

Two simple, rapid and sensitive spectrophotometric methods have been developed for the determination of Sildenafil Citrate (SIL) in pure form and pharmaceutical formulations. The spectrophotometric methods are based on the formation of binary complexes (ion-pair complexes)in dichloromethane (DCM) medium between the drug and tow acidic sulfonephthalein dyes, bromocresol purple (BCP)(method A) and bromophenol blue (BPB) (method B) with absorption maxima at 404 and 410 nm, respectively. The effects of analytical parameters on the reported systems were investigated. The complexation reactions were extremely rapid at room temperature and t¬he absorption values remain unchanged up to 24h. Beer’s law was obeyed in the concentration ranges of 0.6 - 20 and 0.8 -48 µg/ml, detection limits were 0.097 and 0.105µg/ml and the molar absorptivity coefficients were 2.77×104 and 2.60 ×104 L .moL-1.cm-1for BCP and BPB respectively. The proposed methods were successfully applied to the analysis of commercial tablets containing the drugs. Two methods were free-extractive, rapid, and have high sensitivity compared with other previous direct spectrophotometric methods. Interferences of the other ingredients and excipients were not observed.

The Roche Immunoturbidimetric Albumin Method on Cobas c 501 Gives Higher Values Than the Abbott and Roche BCP Methods When Analyzing Patient Plasma Samples.

Serum/plasma albumin is an important and widely used laboratory marker and it is important that we measure albumin correctly without bias. We had indications that the immunoturbidimetric method on Cobas c 501 and the bromocresol purple (BCP) method on Architect 16000 differed, so we decided to study these methods more closely. A total of 1,951 patient requests with albumin measured with both the Architect BCP and Cobas immunoturbidimetric methods were extracted from the laboratory system. A comparison with fresh plasma samples was also performed that included immunoturbidimetric and BCP methods on Cobas c 501 and analysis of the international protein calibrator ERM-DA470k/IFCC. The median difference between the Abbott BCP and Roche immunoturbidimetric methods was 3.3 g/l and the Roche method overestimated ERM-DA470k/IFCC by 2.2 g/l. The Roche immunoturbidimetric method gave higher values than the Roche BCP method: y = 1.111x - 0.739, R² = 0.971. The Roche immunoturbidimetric albumin method gives clearly higher values than the Abbott and Roche BCP methods when analyzing fresh patient samples. The differences between the two methods were similar at normal and low albumin levels.

Structural features of bromocresol purple and its binding sites on human serum albumin for a proton-exchange reaction

Human serum albumin (HSA) levels of identical samples are different when determined using the bromocresol green (BCG) and bromocresol purple (BCP) methods. The aim of this study was to determine this reason for this difference. The pH-dependent color change of the Sulton pH indicators (BCG, BCP, bromophenol blue, bromothymol blue, thymol blue, and phenol red [PR]) complexed with HSA (or poly- L -lysine) in acidic (pH 2.47.8) and basic (pH 7.611.2) solutions was determined with and without inhibition of complex formation by warfarin and ibuprofen. The structures surrounding the drug-binding sites were analyzed by determining the required characteristics of target residues predicted from the experimental data based on the crystallographic data of the drugHSA complexes (2BXD and 2BXG). BCP specifically bound to the warfarin- and ibuprofen-binding sites in acidic pH, but BCG did not. In basic pH, all of the indicators, except for PR, bound to their sites. All of the residues for color change, proton exchange, and binding via electrostatic interaction were present in the binding sites. Given that BCP binds to the warfarin- and ibuprofen-binding sites, the influence of coexisting substances can be experimentally evaluated to facilitate precise measurement using the BCP method.

The impact of change in albumin assay on reference intervals, prevalence of 'hypoalbuminaemia' and albumin prescriptions.

We studied the impact on reference intervals, classification of patients with hypoalbuminaemia and albumin infusion prescriptions on changing from a bromocresol green (BCG) to a bromocresol purple (BCP) serum albumin assay. Passing-Bablok regression analysis and Bland-Altman plot were used to compare Abbott BCP and Roche BCG methods. Linear regression analysis was used to compare in-house and an external laboratory Abbott BCP serum albumin results. Reference intervals for Abbott BCP serum albumin were derived in two different laboratories using pathology data from adult patients in primary care. Prescriptions for 20% albumin infusions were compared one year before and one year after changing the albumin method. Abbott BCP assay had a negative bias of approximately 6 g/L compared with Roche BCG method.There was good agreement (y = 1.04 x - 1.03; R(2 )= 0.9933) between in-house and external laboratory Abbott BCP results. Reference intervals for the serum albumin Abbott BCP assay were 31-45 g/L, different to those recommended by Pathology Harmony and the manufacturers (35-50 g/L). Following the change in method there was a large increase in the number of patients classified as hypoalbuminaemic using Pathology Harmony references intervals (32%) but not when retrospectively compared to locally derived reference intervals (16%) compared with the previous year (12%). The method change was associated with a 44.6% increase in albumin prescriptions. This equated to an annual increase in expenditure of £35,234. We suggest that serum albumin reference intervals be method specific to prevent misclassification of albumin status in patients. Change in albumin methodology may have significant impact on hospital resources.

Clinical decision limits for interpretation of direct bilirubin — A CALIPER study of healthy multiethnic children and case report reviews

ObjectiveMeasurement of total and direct bilirubin is routinely performed for the differential diagnosis of hyperbilirubinemias. The diagnostic efficiency of a test is dependent on the chosen clinical decision limit. This study is designed to address the clinical decision limits for direct bilirubin. Design and methodsRoutine laboratory method was used to measure total and direct bilirubin in children up to the age of 18years. Case study data and serum from a group of healthy children were analyzed and statistical exercise was performed to establish decision limits. ResultsThe reference interval for total bilirubin was 1–12μmol/L and for direct bilirubin 1–9μmol/L with the median direct bilirubin of 3μmol/L. In 17% of children with non-pathological jaundice, median total bilirubin was 173μmol/L, median direct bilirubin was 8μmol/L and median direct bilirubin percent was 49%. From birth direct bilirubin percentage decreased until total bilirubin was 41μmol/L, then it remained at ≤10%. Albumin increased with age, and was on average 2.4g/L higher when measured using bromocresol-green compared with bromocresol-purple. An increased amount of direct bilirubin was observed when albumin (detected using the bromocresol-purple method) was >35g/L. ConclusionsDirect bilirubin concentration of ≥10μmol/L should be used to consider the presence of conjugated hyperbilirubinemia provided that total bilirubin is also above the reference interval. A high direct bilirubin percentage is unlikely to offer any clinical value when total bilirubin is not increased. It is, however, a useful diagnostic tool when there is a persistence of hyperbilirubinemia or when total bilirubin increases during times of stress with direct bilirubin >10%.

Carbamylation of albumin is a cause for discrepancies between albumin assays

BackgroundSeveral investigators have reported discrepancies between the bromocresol-purple (BCP), bromocresol-green (BCG) and immunonephelometric (INP) assays in dialysis patients. This study compared the abovementioned assays and investigated whether hemodialysis itself or carbamylation of albumin is the cause for this discrepancy. MethodsSamples obtained from hemodialysis patients were analyzed by BCP, BCG and INP. Furthermore, albumin was carbamylated in vitro using isocyanate. Isocyanate converts lysine to homocitrulline. ResultsNo differences were observed between samples of the pre- and post-hemodialysis groups for BCP. In the control group, BCG averaged 6g/L higher than INP. BCP did not statistically deviate from INP. In the dialysis group BCG averaged 5g/L higher when compared to INP, whereas BCP averaged 2g/L lower. BCP was affected by carbamylation of albumin. BCG and INP measurements were affected to a much lesser extent. Homocitrulline content of hydrolysates was increased in both the carbamylated albumin as well as in the dialysis population. ConclusionIn a hemodialysis population albumin concentrations are not consistently estimated by both BCG and BCP methods. Relative to INP measurements BCG overestimates the albumin concentration (4–10g/L), whereas BCP leads to an underestimation (0–4g/L). Carbamylation of albumin is the main attributor to the discrepancy found with BCP.

Bromocresol Dye-binding Methods Underestimate Serum Albumin Value in Patients Treated with High Dose of Penicillin G

Background: Various factors contribute to the discrepancies observed between the bromocresol green (BCG) and bromocresol purple (BCP) assays of serum concentration. Either a BCG or a modified BCP assay is a routine laboratory for albumin measurement in Japan. High-dose of penicillin G underestimates serum albumin level using a modified BCP method in vitro. Therefore, we examined the serum albumin level in the patients treated with high-dose of penicillin G and also performed the experiments on coincubation with plasma, or albumin product and penicillin G solution in vitro. Methods: The medical records of 71 patients treated with high-dose of Penicillin G collected between 2009 and 2012 were reviewed for age, gender, biochemistry (total protein, albumin and potassium), underlying diseases and usage of albumin product. Patients were divided into 2 groups: BCG group (N = 38) and a modified BCP group (N = 33). We compared serum albumin levels between two groups. We performed the Original Research Article British Journal of Medicine & Medical Research, 4(6): 1293-1300, 2014 1294 experiments on co-incubation with albumin product or human plasma and penicillin G solution in vitro. Results: Serum albumin levels using a modified BCP assay decreased during the treatment with high dose penicillin G (-0.4 ± 0.1 g/dL), while serum albumin levels by a BCG method did not decrease (0.06 ± 0.05 g/dL). Although only one patient revealed hypoalbuminemia (<2.0 g/dL) by a BCG method (2.6%), ten patients revealed hypoalbuminemia by a modified BCP method (33%). Penicillin G underestimated plasma albumin levels using a modified BCP methods (% underestimation: 42.9 ± 0.0%) more than those using a BCG method (% underestimation: 10.6 ± 0.0%) in co-incubation experiments in vitro. Conclusion: High-dose of penicillin G might cause the underestimation of serum albumin levels using bromocresol dye-binding methods.

Albumin concentration determined by the modified bromocresol purple method is superior to that by the bromocresol green method for assessing nutritional status in malnourished patients with inflammation

The controlling nutritional status (CONUT) score (CS), a simple score for assessing nutritional status, is calculated using laboratory data, including serum albumin concentration. Although dye-binding assays such as the bromocresol green (BCG) and modified bromocresol purple (mBCP) methods are widely used for albumin measurement, acute-phase proteins interfere with the BCG method. We aimed to determine whether the choice of albumin assay affects assessment of nutritional status using CONUT scores (CSs). We measured serum albumin concentrations by the BCG (ALBBCG) and mBCP (ALBmBCP) methods in 44 malnourished inpatients, 27 of whom underwent nutritional intervention, and compared them to 30 age-matched healthy volunteers. In treated patients, CSs were calculated by ALBBCG (CS-BCG) and ALBmBCP (CS-mBCP). C-reactive protein (CRP) concentrations were positively correlated with the difference between ALBBCG and ALBmBCP in malnourished inpatients (r = 0.59, p < 0.001). CS-BCG was always lower than CS-mBCP (lower CS indicates superior nutritional status) in treated patients with persistently high CRP levels. However, in patients whose CRP decreased gradually, this difference diminished over the clinical course. CS-BCG and CS-mBCP were similar throughout their courses in patients with normal CRP concentrations. Adding haptoglobin to the human albumin solutions increased ALBBCG in a dose-dependent manner. The choice of albumin assay affected the assessment of nutritional status using CSs in patients with inflammation. We recommend that the modified BCP assay be used to assess nutritional status, particularly in patients with inflammation.