Free Bilirubin Research Articles

Serum Unbound Bilirubin Versus Transcutaneous Bilirubin in Jaundiced Term Neonates

Transcutaneous bilirubin (TcB) consists of the skin-deposited bilirubin. Free bilirubin speaks to the protein-unbound bilirubin (UB) that can go into the tissues. We expected to portray the connection between UB-TcB and study the section of UB into the skin. We tentatively enlisted 40 neonates and we estimated TcB, UB and all out serum bilirubin. Different locales TcB estimation was performed. TcB has a comparative relationship with UB and TSB.There is asignifigant relationship with TSB, DSB(direct serum bilirubin) between embittered term neonates when contrasted with solid term neonates. There is a critical relationship between free bilirubin in embittered term neonates when contrasted with solid ter.mTcB test doesn't appear to straightforwardly supplant UB estimation. Be that as it may, TcB and UB are connected ,UB adds to the skin bilirubin statement yet it isn't the main bilirubin species estimated by transcutaneous bilirubinometry.

Bilirubin Quantification in Human Blood Serum by Deoxygenation Reaction Switch-Triggered Fluorescent Probe.

A coumarin-based fluorescent compound, bilirubin fluorescent probe N-oxide (BFPNox), was successfully designed and synthesized for highly selective and sensitive detection of free bilirubin with short response time. The fluorescence "turn-on" response of the probe is based on the in situ generated Fe2+-mediated deoxygenation reaction of N-oxide from the diethylarylamine group of the probe, where the group attached to the coumarin π-conjugated system is responsible for the fluorescence quenching state of the probe, BFPNox. Here, the reaction of the added Fe3+ ions with bilirubin produces Fe2+ ions in situ in aqueous buffer. Fluorescence enhancement of BFPNox was achieved by more than 12-fold when a double equivalent of bilirubin solution was added in reaction buffer at pH 7.2 (50 mM HEPES, 5% DMSO) at 25 °C under excitation at 400 nm. It detected free bilirubin as low as 76 nM in an aqueous system without any interference of metal ions, anions, and other important biomolecules with a linear concentration range of 0-10 μM (R2 = 0.991). The probe was also employed in the estimation of free bilirubin in human serum specimens to verify the efficacy of this probe. With these, it is revealed that this probe is a good candidate to be used as a powerful diagnostic tool for the assessment of free bilirubin with significant accuracy and reliability.

Evaluation of Thyroid Function Tests in Children with Chronic Liver Diseases

Objective:Studies examining changes in thyroid function in the course of chronic liver disease have mostly been conducted in adults. The aim of this study was to investigate thyroid dysfunction in children with chronic liver diseases.Methods:Between 2005 and 2018, patients aged up to 18 years of age, diagnosed with chronic liver disease and had thyroid function test results available were included. Anthropometric characteristics, liver and thyroid function results were collected and analyzed.Results:The study included 107 (53 female; 49.5%) patients aged between one month and 18 years-old. Of the 107 patients, 96 (89.7%) had normal thyroid function results, seven (6.5%) had subclinical hypothyroidism (SH) and four (3.7%) had euthyroid sick syndrome. Of the patients with SH, one (14.2%) had glycogen storage diasease, one (14.2%) had biliary atresia, one (14.2%) had undiagnosed cholestatic liver disease, one (14.2%) had Alagille syndrome, one (14.2%) had idiopatic hepatitis, one (14.2%) had progressive familial intra-hepatic cholestasis and one (14.2%) had congenital hepatic fibrosis. Spearman correlation analysis showed a negative correlation between free tri-iodothyronine and direct bilirubin (r=-0.329, p=0.027).Conclusion:In conclusion, euthyroid sick syndrome or SH may affect up to 10% of children with chronic liver diseases. It is suggested that thyroid function should be evaluated in cases of pediatric chronic liver disease at diagnosis and during follow-up. Moreover, this study is the first to show a negative correlation between free T3 levels and direct bilirubin, suggesting a possible association between liver disease severity and thyroid function.

A Paper-Based Surface-Enhanced Raman Scattering (SERS) Biosensor for Label-Free Detection of Serum Bilirubin for Diagnosis of Jaundice

Jaundice continues to be a serious health concern and is among the leading causes of deaths during the first days of newborn babies’ lives. Serum bilirubin is currently being exploited in the clinic as a key biomarker for the diagnosis and management of neonatal jaundice. The commonly used methods for serum bilirubin determination in clinical settings are direct spectroscopic measurement and the diazo reaction method. These methods have drawbacks such as low sensitivity, matrix interference, poor stability, high-cost, professional training, less specificity and tedious sample preparation. Thus, it is very urgent to develop a rapid and economical route for sensitive and specific detection of free bilirubin directly in human serum.Surface-enhanced Raman scattering (SERS) has emerged as a powerful analytical technique for biosensing applications with high sensitivity, molecular specificity, powerful multiplex detection capability, and excellent photostability. This talk will present our recent study on the development of a paper-based SERS biosensor for label-free detection of bilirubin in serum. This biosensor comprises multifunctional graphene oxide-gold nanostar (GO-GNS) hybrids decorated on the filter paper. This biosensor combines the enrichment for serum bilirubin and plasmonic enhancement for Raman signals of bilirubin for boosting the label-free detection sensitivity directly in blood serum without the need for additional sample preparation. Our results demonstrated the excellent detection performance for detection of bilirubin directly in serum in a label-free manner, and the detection results were compared with the commercial diazo reaction method, which justifies the clinical effectiveness and suitability of the present paper-based SERS biosensor. We believe that the present paper-based SERS biosensor has great potential for clinical translation in accurate diagnosis of jaundice and other related diseases.

A study to determine the level of cord blood albumin in predicting neonatal jaundice

Background: Most unconjugated bilirubin formed by the fetus is cleared by the placenta into the maternal circulation. Albumin constitutes 70 - 75% of Plasma oncotic pressure. Another important function of albumin is its antioxidant property. Bilirubin binds to albumin in an equimolar ratio. Free bilirubin is anticipated when the molar bilirubin- to- albumin (B: A) ratio is >0.8 Objective of the study was to predict the proportion of newborn requiring intervention for NH (phototherapy or exchange transfusion) based on cord serum albumin level at birth.Methods: The present prospective study was conducted at Navodaya Medical College, Raichur from October 2018 to November 2019. A total of 180 babies which were born during the study period were included in the study. INCLUSION CRITERIA• Term babies both genders• Mode of delivery (normal and C-section)• Birth weight ≥2.5kg.• APGAR ≥7/10 at 1 min. Cord Serum Albumin level was estimated at birth. Total Serum Bilirubin (TSB) estimation was done at 72-96 hours of age. All the babies were followed up daily for first 4 postnatal days and babies were daily assessed for NH and its severity.Results: In our study nearly 54.4% of them had Cord Serum Albumin levels of less than 2.8 gm/dl, 27.3% of them had albumin levels of 2.9 to 3.3 gm/dl, 18.3% of them had Serum Albumin of 3.4 gm/dl. Out of 180 study subjects, 13.9% of them required phototherapy to treat neonatal hyper bilirubinemia and 2.8% of the study subjects required exchange transfusion.Conclusions: From the present study, cord serum albumin level of ≤2.8g/dl has a correlation with incidence of significant hyperbilirubinemia in term newborns. So, this ≤2.8g/dl of cord serum albumin level can be used as risk indicator to predict the development of significant hyperbilirubinemia.

Evaluation of interference factors in creatinine measurement by using new guideline CLSI EP7-A3

Objective To investigate the interfering factors in the determination of creatinine(Cr) using the American Clinical Laboratory Standards Association (CLSI) EP7-A3 document. Methods According to the CLSI EP7-A3 document, fresh serum (no hemolysis, lipemia, and jaundice) was used on the day of the experiment and confirmed the interfering substances through the pairing difference experiment and the point-to-point analysis method was used in the dose effect experiment to clarify the difference of interfering substances. Results Triglyceride (16.94 mmol/L), dobutamine hydrochloride (4.01 μmol/L), ascorbic acid (298 μmol/L) did not interfere with the determination of Cr. Free bilirubin (684 μmol/L), conjugated bilirubin (684 μmol/L), calcium hydroxybenzene sulfonate (144 μmol/L) and hemoglobin (10 g/L) were used as the maximum concentrations of interferences for the dose effect test, the results showed that the above interferences had negative interference on the determination of Cr. Conclusion According to EP7-A3, it is valuable to evaluate the interference factors of creatinine determination. Key words: Interference experiment; Creatinine

Red blood cell mechanical fragility as potential metric for assessing blood damage caused by implantable durable ventricular assist devices: Comparison of two types of centrifugal flow left ventricular assist devices

Implantable Ventricular Assist Devices (VADs) have become a treatment of choice for patients with end-stage heart failure or cardiogenic shock, significantly increasing both survival rates and the quality of life of patients. Moreover, VAD use is growing as destination therapy for patients who require permanent mechanical cardiac circulatory support. This heightens the need to ensure VAD reliability and safety, even amidst challenges in optimization of pump design for minimal blood damage. Advanced design LVADs like the HVAD (Medtronic, Inc., Minneapolis, MN) and the Heartmate 3 (HM3; Abbott Labs, Chicago, IL) are centrifugal systems that had been favorably compared to the continuous flow axial pumps, such as the HeartMate II (HMII; Abbott Labs, Chicago, IL). While the HVAD and HMII are increasingly utilized in older pediatric populations in addition to the Berlin Heart Excor (Berlin Heart GmbH, Berlin Germany), implementation of VAD support for pediatric patients still lags behind adults. Recently, the HM3 has demonstrated superior performance to the HMII with respect to pump thrombosis in clinical trials and may also find utility in pediatric applications, particularly for adolescents. In this present work, performance of HVAD and HM3 were compared using basic laboratory tests and Red Blood Cell (RBC) Mechanical Fragility (MF), an assay that provides assessment of sub-hemolytic RBC damage which can be caused by VAD operation. RBC MF was assessed using electromagnetically driven bead milling with cylindrical beads in multiple different regimes for different sample stressing configurations. Induced hemolysis in the sample was measured non-invasively at different (increasing) cumulative stress duration intervals, to obtain a MF profile for each stressing regime. In a cohort of 13 HVAD and 7 HM3 patients, blood samples were obtained before surgery and at 1 h, 24 h, 1 week and 4 weeks after surgery. No significant differences were observed between the two VAD devices in conventional hemolysis markers including free hemoglobin, bilirubin, total LDH and haptoglobin, as well as in changes patient hemoglobin. HM3 demonstrated elevated, compared to HVAD, levels of LDH-1 at 24 h (p < 0.05) and 1 week (0.05 < p < 0.1) after surgery, with LDH-1 reverting to about pre-surgery levels at 4 weeks. These differences between pumps may have been attributed to confounders such as duration of cardiopulmonary bypass at time of LVAD implant. By one metric, RBC MF was similarly elevated for HM3 at both 24 h and 1 week after surgery, and also reverted to about pre-surgery levels at 4 weeks. Such changes in RBC MF results were observed for only one of the employed stressing regimes, highlighting the potential importance of matching the applied in vitro stress parameters to the particular nature of in vivo blood damage involved. Forthcoming work is planned for further analysis and reporting on additional aspects of this study.

Localized Controlled Release of Bilirubin from β-Cyclodextrin-Conjugated ε-Polylysine To Attenuate Oxidative Stress and Inflammation in Transplanted Islets.

Islet transplantation has been considered the most promising therapeutic option with the potential to restore the physiological regulation of blood glucose concentrations in type 1 diabetes treatment. However, islets suffer from oxidative stress and nonspecific inflammation in the early stage of transplantation, which attributed to the leading cause of islet graft failure. Our previous study reported that bilirubin exerted antioxidative and anti-inflammatory effects on hypothermic preserved islets, which inspire us to utilize bilirubin to address the survival issue of grafted islets. However, the application of bilirubin for islet transplantation is limited by its poor solubility and fast clearance. In this study, we designed a supramolecular carrier (PLCD) that could improve the solubility of bilirubin and slowly release bilirubin to protect islets after cotransplantation. PLCD was synthesized by conjugating activated β-cyclodextrin (β-CD) to the side chain of ε-polylysine (PLL) and acted as a carrier to load bilirubin via host-guest interactions. The constructed bilirubin supramolecular system (PLCD-BR) significantly improved the solubility and prolonged the action time of bilirubin. In vitro results confirmed that PLCD-BR coculture substantially enhanced the resistance of islets to excessive oxidative stress and proinflammatory stimulation and maximumly maintained the islet function. In vivo, PLCD could prolong drug duration at the transplant site, and the localized released bilirubin could protect the islets from oxidative stress and suppress the production of inflammatory cytokines. Crucially, islet transplantation with PLCD-BR significantly extended the stable blood glucose time of diabetic mice and produced a faster glucose clearance compared to those cotransplanted with free bilirubin. Additionally, immunohistochemical analysis showed that PLCD-BR had superior antioxidative and anti-inflammatory abilities and beneficial effects on angiogenesis. These findings demonstrate that the PLCD-BR has great potentials to support successful islet transplantation.

Preparation of Nitrogen-Doped Mesoporous Carbon for the Efficient Removal of Bilirubin in Hemoperfusion.

The development of bilirubin adsorbent with high selectivity, brilliant adsorption ability, and biocompatibility is still a considerable challenge. In this study, a copolymer-templated nitrogen-doped mesoporous carbon (CTNC) has been prepared via a simple carbonization procedure of well-defined polyacrylonitrile-block-poly(n-butyl acrylate) (PAN-b-PBA) block copolymer precursors. The structure and morphology were characterized by transmission electron microsphere (TEM), adsorption-desorption isotherms, and X-ray photoelectron spectroscopy (XPS). Owing to its high specific area, hierarchical open-porous structure, and the introduction of nitrogen atoms in graphitic sp2 network, the adsorbent CTNC exhibited high removal efficiency toward bilirubin and bile acid from human plasma. The removal rate of bilirubin was more than 50.7% with a minimal loss of albumin. Meanwhile, exceeding 95% of bile acid was eliminated. The effect of albumin on the adsorption kinetic of bilirubin was identified. The result indicated that the adsorption rate of BSA-bonded bilirubin experienced a decline than that of free bilirubin, but the adsorption capacity was still up to 39.8 mg/g within 2 h. Moreover, the effect of porosity and nitrogen contents on bilirubin adsorption ability and blood compatibility were systematically investigated. The material with lower nitrogen content showed only a negligible hemolysis activity. Therefore, the nitrogen-doped mesoporous carbon developed in this work has potential application in blood purification for the efficient removal of bilirubin.

A ratiometric bilirubin sensor based on a fluorescent gold nanocluster film with dual emissions.

Bilirubin originates from hemoglobin metabolism and is an important biomarker for liver function. A ratiometric film sensor based on gold nanoclusters (AuNCs) was fabricated for highly sensitive determination of free bilirubin (fBR). Using bovine serum albumin (BSA) as a template, AuNCs that can emit blue and red fluorescence were prepared by the hydrothermal method at different pH values. Two kinds of AuNCs were incorporated into a single film by the layer-by-layer assembly (LBL) technique. The obtained thin-film showed dual fluorescence peaks excited at 372 nm, corresponding to the blue (443 nm) and red (622 nm) emissions of AuNCs respectively. When fBR interacted with the film, both fluorescence peaks were quenched at different degrees. A ratiometric method for fBR detection was established based on the fluorescence intensity ratio of the two emissions. The linear calibration curve for fBR lay in the concentration range of 0.01-2.00 μmol L-1 with a detection limit of 8.90 ± 0.34 nmol L-1 (S/N = 3). The film sensor showed a quick and sensitive response to fBR and could detect fBR in real samples with satisfactory results.

Acute and sub-chronic oral toxicity assessment of the leaf aqueous extract of &lt;i&gt;Kalanchoe crenata&lt;/i&gt; (Crassulaceae)

Previous studies demonstrated that the leaves of Kalanchoe crenata (Crassulaceae) possess analgesic, anti-inflammatory, anticonvulsant and cardiovascular activities but nothing is known about the toxicity of this plant material. The objective of the present study was to evaluate the acute and sub-chronic toxicities of the aqueous extract of the leaves of K. crenata (AEKC) prepared as a dry leaves decoction. Acute oral toxicity of the AEKC was evaluated in mice at doses 2, 4, 6, and 8 g/kg. Animals were observed for 3 hours post administration for signs and symptoms of intoxication. Survivors were followed up for 14 days after treatment. Wistar rats of both sexes were used for sub-chronic toxicity. They were orally treated with the AEKC at doses of 300, 600 and 1200 mg/kg/day for 4 consecutive weeks. They were further euthanized and blood was collected for biochemical and hematological analyses. A single acute administration of AEKC reduced the sensitivity to pain and the mobility of animals. These behavioral modifications disappeared 3 hours after administration. Only the dose of 8 g/kg caused the death of one female mouse out of 6, inferring a LD50 greater than 8 g/kg. The daily administration of AEKC did not induce mortality, behavioral modifications, significant variations of body weight, relative weights of the liver and kidney and plasma content of Alanine amino transferase (ALAT) and aspartate amino transferase (ASAT). Besides, no significant difference was observed on glomerular filtration rate and other parameters of renal excretion. Meanwhile, at the dose of 300 mg/kg/day, a significant increase in total bilirubin, free bilirubin and a significant decrease in conjugated bilirubin and plasma creatinine were registered. These results suggest that the aqueous extract of the leaves of K. crenata can be classified as a non-toxic substance. However, attention should be paid on the hepatic function.Keywords: Acute and sub-chronic toxicity, aqueous extract, Kalanchoe crenata, Crassulaceae

Review of bilirubin neurotoxicity I: molecular biology and neuropathology of disease.

Despite the availability of successful prevention strategies to prevent excessive hyperbilirubinemia, the neurological sequelae of bilirubin neurotoxicity (BNTx) still occur throughout the world. Kernicterus, encephalopathy due to BNTx, is now understood to be a spectrum of severity and phenotypes known as kernicterus spectrum disorder (KSD). A better understanding of the selective neuropathology and molecular biology of BNTx and using consistent clinical definitions of KSDs as outcome measure can lead to more accurately predicting the risk and causes of BNTx and KSDs. In Part I of our two-part review, we will summarize current and recent advances in the understanding of the selective neuropathology and molecular biology of the disease. Herein we emphasize the role of unbound, free unconjugated bilirubin as well as genetic contributions to the susceptibility BNTx and the development of KSDs. In Part II, we focus on current and possible novel methods to prevent BNTx and ABE and treat ABE and KSDs.

Establishment of a method for detecting neonatal serum free bilirubin by high performance liquid chromatography

Objective To establish the HPLC method for detecting neonatal serum FB. Methods The chromatographic column was ODS-C18 column (150.0 mm × 4.6 mm × 5.0 μm). The mobile phase of methanol-ammonium acetate ice acetic acid solution was 96:4, flow rate 0.9 ml/min, column temperature 30℃, detection wavelength 458 nm, and injection volume 20 μl. The precision, accuracy, recovery rate, and stability of the method were examined. The differences between different groups were calculated by SPSS software package. Results The retention time of FB was 9.583 min. The lower limit of quantification was 0.625 μmol/L. The linear range of serum FB was 0.625-160.000 μmol/L. The standard curve: y=73 403x – 22 975. The r2 is 0.999 5. The slope deviation was 726.649 686 4. The intercept deviation was 30 119.924 55. The average intra-day and inter-day precision of each gradient concentration were less than 5%. The relative recovery was 95%-105%. Different gradient concentration extraction recovery range was 68%-78%. The repeated freeze-thaw stability average RSD was 3.020%. The average RSD value of stability under different storage conditions was 0.565%. The concentration of serum FB in 13 jaundiced newborns we measured were (548.20±107.19) nmol/L. Conclusion HPLC detecting serum FB is simple in operation, and has high specificity, accuracy, precision and stability. Key words: Serum free bilirubin (FB); Neonates; HPLC; Detection

A graphene oxide-gold nanostar hybrid based-paper biosensor for label-free SERS detection of serum bilirubin for diagnosis of jaundice

We report a paper-based surface-enhanced Raman spectroscopy (SERS) biosensor integrating the enrichment capability, namely enPSERS biosensor, for the sensitive, label-free detection of free bilirubin in blood serum for the accurate diagnosis of jaundice and its related diseases. This biosensor comprises multifunctional graphene oxide-plasmonic gold nanostar (GO-GNS) hybrids decorated on the filter paper, which integrates the high sensitivity of SERS detection, enrichment for serum bilirubin and fluorescence superquenching capability of GO-GNS hybrids for sensitive detection of serum bilirubin. The study of adsorption kinetics reveals that both electrostatic and π-π interactions between the GO-GNS hybrids and targets are responsible for the enrichment of bilirubin, and the adsorption process follows the pseudo-second-order kinetic model. The results of SERS detection of bilirubin in blood serum show two differential linear response ranges from 5.0 to 150 μM and 150–500 μM with the detection limit as low as 0.436 μM. The comparison of the results obtained from our present enPSERS biosensor with the commercial diazo reaction method for determination of free bilirubin in blood serum reveals the clinical effectiveness and suitability of the developed paper-based SERS biosensor. We believe that this sensitive and label-free SERS biosensor holds considerable promise for clinical translation in accurate diagnosis of jaundice.

Clinical characteristics and treatment options of hearing impairment caused by hyperbilirubinemia

SummaryNeonatal hyperbilirubinemia is the most common clinical symptom in neonates. When the concentration of free bilirubin in blood is too high, it crosses through the blood-brain barrier and selectively deposits in specific brain nuclei to cause neurotoxicity and bilirubin neurological dysfunction. The auditory nervous system is highly sensitive to bilirubin. Therefore, auditory neuropathy is the most important or even the only clinical symptom of bilirubin neurological dysfunction. Chronic bilirubin encephalopathy can be classified to three types as mild, moderate and severe，according to the audiological manifestations and other neurological sequelae. Early recognition and intervention of bilirubin-induced hearing impairment is of great significance to improve the speech recognition rate of the referred children. This article reviews the most important studies about the clinical characteristics, pathogenesis and treatment of bilirubin-induced hearing impairment.

Designed Amphiphilic Polystyrene as Surfactant for Oligo(p-phenylenevinylene)-Incorporated PS Nanobeads and Visual Detection of Bilirubin in Human Blood Serum

Amphiphilic polystyrene having pendant glucuronic acid (PS-DGlu) was designed and systematically synthesized to be used as a stabilizing agent in styrene miniemulsion polymerization, while covalently incorporating oligo(p-phenylenevinylene) (OPV)-based fluorophore to prepare PSG-OPV-n. This OPV fluorophore was incorporated with an aim to work as a signal transducer, while glucuronic acid on the surface of PS nanobeads would act as the water solubilizing moiety for PS to enable it to function as surfactant and also serve as an interaction site for free bilirubin to facilitate noncovalent interaction via hydrogen bonding. Efficient energy transfer from OPV to bilirubin was observed, owing to the appreciable spectral overlap between emission of OPV and absorption of bilirubin. Visual color change from blue to bluish green was observed under an UV lamp after the addition of bilirubin into the polymer. Selectivity of the sensor was checked among the pool of other interferences, such as glucose, sucrose, metal ...

A novel assay for triglycerides using glycerol dehydrogenase and a water-soluble formazan dye, WST-8.

BackgroundThe glycerol-3-phosphate (GPO)-peroxidase (POD) chromogenic method is one of the most widely used methods to assay triglycerides. However, it is well known that peroxidase is affected by reducing agents, and recently, it has been reported that some materials affect its activity. Moreover, there is a high possibility of non-specific reaction, as the method uses many enzymes. Against this background, we developed a simpler assay method for triglycerides without using peroxidase.MethodsTriglycerides were hydrolysed to glycerol and fatty acids by lipoprotein lipase followed by the oxidation of glycerol to dihydroxyacetone with simultaneous production of NADH by glycerol dehydrogenase. To overcome incomplete conversion of glycerol to dihydroxyacetone by glycerol dehydrogenase at equilibrium, we added 2-(2-methoxy-4-nitrophenyl)-3–(4-nitrophenyl)-5–(2,4-disulfophenyl)-2 H-tetrazolium monosodium salt (WST-8) to the reaction mixture to remove NADH, allowing the reaction to complete while showing stoichiometric production of reduced WST-8.ResultsThe reaction was linear up to 6.4 mmol/L. The mean intra-assay ( n = 20) and inter-assay ( n = 20) imprecision, as determined by replicate analysis of three pooled human serum samples with different triglyceride concentrations, were 1.1–2.3% and 1.1–1.5% coefficient of variation (%CV), respectively. No interference by 2.5 g/L haemoglobin, 65 μmol/L free bilirubin and 359 μmol/L conjugated bilirubin was observed. The equation obtained in comparison with that by the GPO-POD method including endogenous glycerol-eliminating step was: y = 1.0002x + 0.0395 mmol/L; r = 0.999; Sy/x = 0.049 mmol/L; n = 97.ConclusionOur method is an accurate, yet simpler and more sensitive for the quantitative analysis of triglycerides.

A Gold Nanoclusters Film Supported on Polydopamine for Fluorescent Sensing of Free Bilirubin.

Serum bilirubin is an important biomarker for the diagnosis of various types of liver diseases and blood disorders. A polydopamine/gold nanoclusters composite film was fabricated for the fluorescent sensing of free bilirubin. Bovine serum albumin (BSA)-stabilized gold nanoclusters (AuNCs) were used as probes for biorecognition. The polydopamine film was utilized as an adhesion layer for immobilization of AuNCs. When the composite film was exposed to free bilirubin, due to the complex that was formed between BSA and free bilirubin, the fluorescence intensity of the composite film was gradually weakened as the bilirubin concentration increased. The fluorescence quenching ratio (F0/F) was linearly proportional to free bilirubin over the concentration range of 0.8~50 μmol/L with a limit of detection of 0.61 ± 0.12 μmol/L (S/N = 3). The response was quick, the film was recyclable, and common ingredients in human serum did not interfere with the detection of free bilirubin.

Interference in specialized coagulation assays affecting the protein C pathway: Effects of marked haemolysis, hyperbilirubinaemia and lipaemia on chromogenic and clotting tests on two coagulation platforms.

Haemolysis, lipaemia and hyperbilirubinaemia represent important challenges in the coagulation laboratory. Test results are influenced not only by the degree of the interfering substance but also by the detection system. We investigated the interference of free haemoglobin, triglycerides and bilirubin on a "modified activated protein C (APC) resistance test," protein C activity and protein S (antigen and activity) with two coagulation analysers, the STA-R Evolution and the ACL TOP. Haemolysis interfered with all assays on the STA-R Evolution resulting in higher levels of protein C activity and lower levels of protein S and a decreased APC ratio compared with baseline levels. On the ACL TOP, haemolysis only diminished protein S antigen levels and the APC ratio. Lipaemia increased protein C activity and protein S activity levels on the STA-R Evolution, whereas APC-R decreased on the ACL TOP and protein S antigen could not be measured in any lipaemic samples. Hyperbilirubinaemia caused an increase in protein C activity and in protein S antigen and a decrease in APC-R on the STA-R Evolution, whereas a decline of protein C activity, of protein S antigen and of the APC-R could be observed in icteric samples on the ACL TOP. Our data show that the degree of interference associated with haemolysis, lipaemia and hyperbilirubinaemia is different in several assays. Some assay limitations were not reproduced, and limitations stated in kit inserts cannot be assumed to apply to all analysers.

The Effect of Lipid Emulsions on Free Fatty Acids and Free Bilirubin in Premature Newborns

The Effect of Lipid Emulsions on Free Fatty Acids and Free Bilirubin in Premature Newborns