Detection Of Glycated Hemoglobin Research Articles

Analysis of hemoglobin variants in Tianjin City and neighboring areas

To determine the types and proportion of common hemoglobin variants in Tianjin and surrounding areas, to analyze the recognition ability and the effects of hemoglobin variants on experimental results in two commonly used glycated hemoglobin systems, so as to provide data support for the consistency of HbA1c detection in Tianjin City. A case-control study was used for retrospective analysis,156 specimens with abnormal electrophoretic peaks in the detection of glycated hemoglobin were collected from more than 50 000 specimens of patients in Chu Hsien-I Memorial Hospital of Tianjin Medical University between June 2020 and December 2020. Determined their hemoglobin mutation sites by DNA sequencing, and compared the values of hemoglobin variants on glycated hemoglobin detection values by high performance liquid chromatography and capillary electrophoresis. SPSS 23 was used to calculate the blood routine results of the variant specimens, and compared with the normal reference interval. The results showed that DNA sequencing identified 21 hemoglobin variants, of which 11 were α strand variants and 10 were β strand variants. In addition, an unreported hemoglobin variant was identified, Hb Headington (HBB: c.217A>C). The HbA1c of 11 variants including Hb G-Honolulu, Hb Queens, Hb Q-Thailand, Hb J-Broussais, Hb O-Indonesia, Hb G-Coushatta, Hb G-Taipei, Hb E, Hb Headington, Hb New York and Hb D-Los Angeles were shifted by more than 7% when measured by high-performance liquid chromatography. Patients with the Hb Q-Thailand and Hb E cause reduced MCV and MCH. In conclusion, an unreported hemoglobin variant was found from Tianjin and neighboring areas. Patients with the Hb Q-Thailand and Hb E cause reduced MCV and MCH. 11 of these hemoglobin variants interfered with the detection of glycated hemoglobin using high-performance liquid chromatography, resulting in inaccurate results.

Investigation of the recognition interaction between glycated hemoglobin and its aptamer by using surface plasmon resonance

Glycated hemoglobin (HbA1c) has been widely explored as an important marker for monitoring and diagnosing diabetes. Due to the advantages of high selectivity, easy preparation, and convenient preservation of aptamers, research on glycated hemoglobin detection utilizing aptasensors has received much attention in recent years. However, factors such as the pH and the salt concentration of the solution and the structure of the aptamer could influence the interactions between HbA1c and the aptamer. In this study, the factors were evaluated using surface plasmon resonance (SPR). The results show that the pH and the salt concentration can greatly affect the formation of a complex between the aptamer and HbA1c. In the stereostructure of the aptamer, loop L1 may be an important motif for recognizing glycated hemoglobin. In addition, the best condition for detecting HbA1c was at pH 6, with a high sensitivity and a low limit of detection(LOD) (1.06 × 10−3RUnM /2.55 nM). The results also demonstrated that the use of an SPR aptamer biosensor can be a sensitive technique to improve the accuracy and correctness of HbA1c measurement.

High sensitivity label-free refractometer based biosensor applicable to glycated hemoglobin detection in human blood using all-circular photonic crystal ring resonators

Abstract Lab-on-a-chip integrated optical biosensors have shown useful in non-invasive detection of biomaterials. Furthermore they are immune to electromagnetic interference rather than their electronic counterparts. In this paper, an all-optical photonic crystal (PhC)-based biosensor is presented. The biosensor is made up of two PhC-based W 1 waveguides which are critically coupled to a PhC-based ring-resonator (RR). The hub of the ring is designed in an all-circular quasi-crystal fashion to enhance output efficiency as well as easy injection of analyte. This PhCRR can distinguish 85 ± 15% of amplitude change via resonant wavelength shift of 0.75 ± 0.15 nm, or equally a 0.005 change in the refractive index unit (RIU). By introducing any change in the optical characteristics of desired biomaterials (i.e. refractive index of glycated hemoglobin), the resonance frequency of resonator changes and due to its high quality factor and sensitivity, a large amplitude difference appears in the output. The proposed glycated hemoglobin biosensor works in the wavelength interval of 1.545–1. 565 μ m , and its quality factor, figure of merit (FOM) and sensitivity are calculated to be 2500 ± 500 , 1400 ± 200 RIU−1 and 690 ± 50 nm/RIU, respectively. The simulations are performed in two-dimensional and finite difference time domain (FDTD) algorithm is used to numerically solve time-dependent Maxwell-equations within propagation domain.

Glycated hemoglobin detection with electrochemical sensing amplified by gold nanoparticles embedded N-doped graphene nanosheet

In the diabetic patients the level of glucose must be determined without any short term fluctuations. The level of Glycated hemoglobin (HbA1c) is accordingly examined for checking diabetes mellitus. HbA1c is considered one of the primarily factor to discern the concentration of average plasma glucose over a long-drawn-out period. In our work, we describe a construction of biosensor which is based on fructosyl amino-acid oxidase (FAO) immobilized nitrogen-doped graphene/gold nanoparticles (AuNPs)/fluorine doped tin oxide (FTO) glass electrode. This constructed biosensor exhibits a wide linear range of 0.3 to 2000μM in response to HbA1c at +0.2V. Consequently, the detection limit of 0.2μM and good stability (4 months) were achieved. The electrocatalytic activity of this sensor was good as a result of synergistic effect of graphene and AuNPs (2D and 0D nanomaterials). The charge transfer resistance was decreased which was observed by electrochemical impedance spectroscopy (EIS) study. The graphene/AuNPs composites film reveals a distinguished electrochemical response to fructosyl valine (FV) which demonstrates a promising application for electrochemical detection of HbA1c in human blood samples.

Homogeneous Immunosensor Based on Luminescence Resonance Energy Transfer for Glycated Hemoglobin Detection Using Upconversion Nanoparticles.

We report an immunosensor based on luminescence resonance energy transfer (LRET) to detect homogeneous glycated hemoglobin (HbA1c). This system uses near-infrared (NIR)-to-visible rare-earth upconversion nanoparticles (UCNPs), such as NaYF4:Yb(3+), Er(3+), as the donor and HbA1c as the acceptor. The HbA1c used as target molecules showed absorption at 541 nm, which corresponded with the emission of the UCNPs. When HbA1c was added, LRET occurred between the donor and acceptor under laser irradiation of 980 nm because of the specific recognition between the anti-HbA1c monocolonal antibody-functionalized UCNPs and HbA1c. In the absence of HbA1c, there was strong upconversion luminescence intensity; however, in its presence, the distance between the donor and acceptor decreased to enable energy transfer, consequently quenching the luminescence of the UCNPs. The proposed method was successfully applied to HbA1c detection in blood samples. Our results indicate that the LRET-based immunosensor allows for specific and sensitive detection of HbA1c in a homogeneous manner.

Glycated Hemoglobin Detection in Clinical Blood Samples by Using CMOS Poly-silicon Sub-micron Wire Biosensor

This paper presents hemoglobin (Hb) and glycated hemoglobin (HbA1c) in clinical blood samples detection by a poly-silicon sub-micron wire (poly-Si SW) biosensor. HbA1c examination has been a better method in long-term diabetes monitoring without day-to-day glucose level fluctuations. Currently, HbA1c test need to be performed in laboratory or hospital because of complicated operation and the need of well-trained operator. This limits its applications in homecare application and resource limited area. The sensing results of poly-Si SW were compared to the standard Hb and HbA1c measurement methods and showed comparable results. Compared with conventional examination methods, using CMOS poly-Si SW biosensor can economize the cost of diagnoses and easily integrate with different functional systems. Based on our previous results, our work could potentially be applied for next generation healthcare application.