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1.
Ultramicroscopy ; 249: 113728, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37030158

ABSTRACT

One of the brilliant ideas of John Spence when he saw the first diffraction patterns from the Linac Coherent Light Source was that one could solve the crystallographic phase problem by utilising the intensities between Bragg peaks. Because these intensities are due to the Fourier transform of the shape of the crystal, the approach came to be known as "shape-transform phasing." Shape-transform phasing was developed over the next ten years and formed the basis for many other interesting ideas and pursuits. Here we describe the current best implementation of the original idea using a lattice occupancy formalism and show that certain types of crystal defects can also be modelled via this approach, allowing the molecular structure to be recovered from the additional information offered by the inter-Bragg intensities from these crystal defects.

2.
Opt Express ; 30(6): 8898-8916, 2022 Mar 14.
Article in English | MEDLINE | ID: mdl-35299332

ABSTRACT

X-ray tomography is widely used for three-dimensional structure determination in many areas of science, from the millimeter to the nanometer scale. The resolution and quality of the 3D reconstruction is limited by the availability of alignment parameters that correct for the mechanical shifts of the sample or sample stage for the images that constitute a scan. In this paper we describe an algorithm for marker-free, fully automated and accurately aligned and reconstructed X-ray tomography data. Our approach solves the tomographic reconstruction jointly with projection data alignment based on a rigid-body deformation model. We demonstrate the robustness of our method on both synthetic phantom and experimental data and show that our method is highly efficient in recovering relatively large alignment errors without prior knowledge of a low resolution approximation of the 3D structure or a reasonable estimate of alignment parameters.

3.
Malays Orthop J ; 15(3): 15-20, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34966490

ABSTRACT

INTRODUCTION: Humeral shaft fractures are the most common injury sustained in arm wrestling, and its various biomechanical, anatomical, kinematic and electromyographic aspects have been studied and reported. We present a series of six cases of humeral shaft fractures in the arm wrestlers and a review of basic science studies to determine the factors contributing to their causation. MATERIALS AND METHODS: Six humeral shaft fractures associated with arm wrestling were treated between December 2018 and January 2020. The medical records and radiographs were retrospectively reviewed. In addition, the characteristics of the patients, their opponents, and the fractures were noted in a pre-designed data sheet. RESULTS: There were six men with an average age of 27.5 years (SD ± 8.9). All were amateurs who were occasional arm wrestlers. Three fractures each were sustained in the sitting and standing position, four in the losing phase, one in the winning phase, and one in the stalling phase. The dominant side humerus was involved in all but one case. The fracture types were 12-A1 (n=4); 12-B1 (n=1); 12-A2 (n=1). Three fractures were treated by open reduction and internal fixation, while three were treated conservatively with satisfactory healing. CONCLUSION: Humeral shaft fractures in arm wrestling are common in amateurs. There is no association of the fracture with the position of the players or the phase of the match. However, arm wrestlers should be aware of this complication and should receive proper guidance to reduce the risk of humeral shaft fractures.

4.
Malays Orthop J ; 14(2): 39-46, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32983376

ABSTRACT

INTRODUCTION: Lower limb amputations have a profound impact on the quality of life (QoL) of the patients. This study was done to assess the QoL of patients with transtibial (below-the-knee) amputations (TTA) and transtibial amputees fitted with prosthesis. MATERIAL AND METHODS: A case-control study of patients who had undergone TTA from 2015 to 2018 was conducted in Raja Isteri Pengiran Anak Saleha Hospital (RIPAS). Complete data was available for 30 subjects and it was compared with 30 diabetic, non-amputee patients matched for age and gender. QoL was assessed using the RAND 36-Item Health Survey (SF-36) and the functional outcome of prosthesis-fitted transtibial amputees was assessed using the Houghton Scale. RESULTS: Almost all cases of TTA were a result of vascular problems related to diabetes and chronic renal disease (n=29; 97%). Eighteen (60%) participants were fitted with prosthesis and 15 (50%) reported having phantom pain. QoL of participants was found to be significantly lower than that of age and sex-matched diabetic non-amputees with regards to physical functioning, role limitation due to physical health, emotional well-being, social functioning, and bodily pain. The mean Houghton Score for participants fitted with prosthesis was 4.89 (SD= 2.83) suggesting low functional outcome. CONCLUSION: TTA has a negative impact on the QoL of patients, especially in terms of functionality. The availability of prosthesis does not significantly improve the quality of life except in the physical functioning domain. Emotional well-being should be emphasised more in the rehabilitation process as this study found poor emotional well-being among participants.

5.
Article in English | WPRIM (Western Pacific) | ID: wpr-822302

ABSTRACT

@#Introduction: Lower limb amputations have a profound impact on the quality of life (QoL) of the patients. This study was done to assess the QoL of patients with transtibial (below-the-knee) amputations (TTA) and transtibial amputees fitted with prosthesis. Materials and Methods: A case-control study of patients who had undergone TTA from 2015 to 2018 was conducted in Raja Isteri Pengiran Anak Saleha Hospital (RIPAS). Complete data was available for 30 subjects and it was compared with 30 diabetic, non-amputee patients matched for age and gender. QoL was assessed using the RAND 36Item Health Survey (SF-36) and the functional outcome of prosthesis-fitted transtibial amputees was assessed using the Houghton Scale. Results:Almost all cases of TTA were a result of vascular problems related to diabetes and chronic renal disease (n=29; 97%). Eighteen (60%) participants were fitted with prosthesis and 15 (50%) reported having phantom pain. QoL of participants was found to be significantly lower than that of age and sex-matched diabetic non-amputees with regards to physical functioning, role limitation due to physical health, emotional well-being, social functioning, and bodily pain. The mean Houghton Score for participants fitted with prosthesis was 4.89 (SD= 2.83) suggesting low functional outcome. Conclusion: TTA has a negative impact on the QoL of patients, especially in terms of functionality. The availability of prosthesis does not significantly improve the quality of life except in the physical functioning domain. Emotional well-being should be emphasised more in the rehabilitation process as this study found poor emotional well-being among participants.

6.
Malays Orthop J ; 11(1): 77-78, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28435582

ABSTRACT

Transient osteoporosis of the hip (TOH) is a benign, selflimiting condition characterised by acute onset groin pain in adults. Early diagnosis is important to differentiate it from progressive conditions such as osteonecrosis. We report on a middle-aged male who presented with right groin pain without any prior trauma. The diagnosis of transient osteoporosis of hip was confirmed by Magnetic Resonance Imaging (MRI) and he was successfully treated with a course of Alendronate sodium, anti-inflammatory analgesics and a period of non-weight bearing ambulation.

7.
Malays Orthop J ; 10(3): 39-41, 2016 Nov.
Article in English | MEDLINE | ID: mdl-28553447

ABSTRACT

Subcutaneous emphysema is the presence of gas or air in the subcutaneous tissue plane. The term is generally used to describe any soft tissue emphysema of the body wall or limbs, it can result from benign causes, most commonly secondary to trauma or from a life-threatening infection by gas gangrene or necrotising fasciitis. A case of subcutaneous emphysema involving the upper limb resulting from a trivial laceration to the elbow is reported and the importance of distinguishing between the two causes of subcutaneous emphysema is highlighted.

8.
Struct Dyn ; 2(2): 024103, 2015 Mar.
Article in English | MEDLINE | ID: mdl-26798791

ABSTRACT

Determination of fast structural changes of biomolecules is usually performed on crystalline samples in a time-resolved pump-probe experiment. Changes in the structure are found by the difference Fourier method using phases of a known reference structure. As we showed recently, such changes can also be determined from diffraction of uncrystallized molecules in random orientations. In this case, the difference in the angular correlations of the diffraction patterns is used to find structural changes. Similar to the difference Fourier method, there is no need for iterative phasing. We validated this approach previously with simulations in the absence of noise. In this paper, we show that the effects of noise can be adequately suppressed by averaging over a sufficiently large ensemble as they can be obtained using an X-ray free electron laser.

9.
Malays Orthop J ; 9(3): 44-48, 2015 Nov.
Article in English | MEDLINE | ID: mdl-28611909

ABSTRACT

INTRODUCTION: Passive Straight Leg Raising Test (PSLRT) is one of the most commonly performed test in clinical practice. The purpose of this study was to survey the practice and interpretation of PSLRT amongst clinicians working in a tertiary care hospital. METHODS: A 15 item questionnaire survey was developed covering various aspects of PSLRT. Orthopaedic surgeons(n=15), neurosurgeons (n=7) and physiotherapists (n=9)were identified as clinicians performing this test regularly and were approached to take part in the survey. RESULTS: The PSLRT was used in all cases of back and leg pain by 68% and correctly performed by 30/31. There was a wide variation in the angle at which it was considered positive (median 45 degrees; range 10-90 degrees). Only 7/31 correctly recognised reproduction of leg pain as indicative of a positive PSLRT. The sitting /distraction SLRT andwell leg / cross SLRT was performed only by 3/31 and 16/31 of clinicians respectively. 90% felt that a positive PSLRT suggested nerve root irritation and 57% thought it was due to stretch of dura and / or nerve root. 23/31 clinicians felt that PSLRT was useful or very useful and 90% reported that result of PSLRT would affect the way they treat a patient. CONCLUSIONS: PSLRT is widely used, correctly performed and felt to be useful in practice. But the interpretation of a positive test, understanding of its mechanism and useof variations is poor. There is a need to improve the interpretation and understanding of PSLRT amongst its users.

10.
Philos Trans R Soc Lond B Biol Sci ; 369(1647): 20130332, 2014 Jul 17.
Article in English | MEDLINE | ID: mdl-24914159

ABSTRACT

We propose a method for deducing time-resolved structural changes in uncrystallized biomolecules in solution. The method relies on measuring the angular correlations of the intensities, when averaged over a large number of diffraction patterns from randomly oriented biomolecules in solution in a liquid solvent. The experiment is somewhat like a pump-probe version of an experiment on small angle X-ray scattering, except that the data expected by the algorithm are not just the radial variation of the averaged intensities. The differences of these correlation functions as measured from a photoexcited and dark structure enable the direct calculation of the difference electron density with a knowledge of only the dark structure. We exploit a linear relation we derive between the difference in these correlation functions and the difference electron density, applicable for small structural changes.


Subject(s)
Algorithms , Electrons , Lasers , Models, Theoretical , Molecular Conformation , X-Ray Diffraction/methods , Time Factors
11.
J Phys Chem Lett ; 5(1): 212-219, 2014 Jan 02.
Article in English | MEDLINE | ID: mdl-24563725

ABSTRACT

We report infrared studies of adsorbed atomic oxygen (epoxide functional groups) on graphene. Two different systems are used as a platform to explore these interactions, namely, epitaxial graphene/SiC(0001) functionalized with atomic oxygen (graphene epoxide, GE) and chemically reduced graphene oxide (RGO). In the case of the model GE system, IR reflectivity measurements show that epoxide groups distort the graphene π bands around the K-point, imparting a finite effective mass and contributing to a band gap. In the case of RGO, epoxide groups are found to be present following the reduction treatment by a combination of polarized IR reflectance and transmittance measurements. Similar to the GE system, a band gap in the RGO sample is observed as well.

12.
Singapore Med J ; 53(2): 124-7, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22337188

ABSTRACT

INTRODUCTION: Burn injuries are a public health concern across the world, particularly in Southeast Asia, where epidemiological data is lacking. This retrospective study was conducted to assess the epidemiology of patients with burns treated at a major referral hospital in Brunei Darussalam, with particular reference to demographics and aetiology. METHODS: All patients were referred to and treated at the Burns Unit, where data was recorded by the on-duty nurse on a pre-designed form at the first attendance. A total of 211 patients (111 male, 100 female), comprising 10 inpatients and 201 outpatients, were treated during the study period. RESULTS: The average age of the patients was 19.6 ± 20.9 (median 10, range < 1-90) years. 67 (32%) patients were under two years of age. Scalding due to hot liquids was the most common cause (78.2%), followed by flame and contact burns. The majority of burns were sustained indoors either at home or at work (87.2%). The total body surface area (TBSA%) for the whole sample was 3.7% ± 7.9% (median 2%; range 1%-90%). Patients with flame burns (n = 19) were older and had larger TBSA% (p < 0.05). Inpatients had significantly higher TBSA% compared to outpatients (28.2% ± 26% versus 2.5% ± 2.1%; p < 0.005). CONCLUSION: Scald burns sustained indoors are the most common across all age groups. Although the TBSA is small, a large number of children are affected. There is a need for burns prevention education programme in Brunei Darussalam.


Subject(s)
Burns/epidemiology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Brunei/epidemiology , Burn Units/statistics & numerical data , Burns/etiology , Burns/pathology , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Retrospective Studies , Young Adult
13.
Climacteric ; 15(2): 163-6, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22066863

ABSTRACT

OBJECTIVE: Low bone mineral density (BMD) is a major risk factor for fragility fractures in osteoporosis. In recent studies, its use with clinical risk factors has been shown to enhance prediction of fragility fractures. The present study was done to assess BMD in Indian patients with fragility fractures using digital X-ray radiogrammetry (DXR-BMD). METHODS: A total of 228 patients (64 male and 164 female) admitted to an Orthopedic Hospital for management of fragility fracture were recruited. For each patient, DXR-BMD was obtained from an anteroposterior radiograph of the non-dominant hand. RESULTS: The number of subjects with hip fracture was 104 (40 male, 64 female). Vertebral fractures were seen in 67 patients (11 male, 56 female) and distal radial fracture in 57 patients (13 male, 44 female). The DXR-BMD (g/cm(2)) was significantly lower in subjects with any fragility fracture (0.51 vs. 0.58 in men and 0.41 vs. 0.54 in women). When compared to the age-matched normative reference data by decade, all subjects with fragility fracture had significantly lower DXR-BMD except male subjects in the age decade of 40-49 years. CONCLUSION: This study confirms lower DXR-BMD in Indian subjects with fragility fractures. This may have a potential role in fracture prediction when used with clinical risk factors in the Indian population.


Subject(s)
Bone Density , Fractures, Spontaneous/etiology , Hand/diagnostic imaging , Hip Fractures/etiology , Radius Fractures/etiology , Spinal Fractures/etiology , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Fractures, Spontaneous/physiopathology , Humans , India , Male , Middle Aged , Radiography , Young Adult
14.
Singapore Med J ; 52(5): 346-50, 2011 May.
Article in English | MEDLINE | ID: mdl-21633768

ABSTRACT

INTRODUCTION: Melioidosis caused by Burkholderia pseudomallei is an infectious disease endemic to Southeast Asia and northern Australia. It has a broad spectrum of clinical manifestations and high mortality, and can mimic other infectious diseases. The aim of this study was to review cases of melioidosis of the extremities in Brunei Darussalam. METHODS: Culture-positive cases for Burkholderia pseudomallei in Raja Isteri Pengiran Anak Saleha Hospital were identified from records in the Microbiology Department. The case notes were reviewed to identify patients who were treated for problems affecting the extremities. 14 (13 males and one female) out of 48 patients were identified. RESULTS: The median age of the patients was 45 (range 14-55) years. Septicaemia was the most common presenting feature in 11 patients. Multisystem involvement was noted in eight patients, diabetes mellitus in nine patients and other risk factors in two patients. Blood culture was positive in ten patients and pus culture in 11 patients. The presentations noted were cellulitis of the limbs, abscess, osteomyelitis (three patients each) and septic arthritis (five patients). Orthopaedic intervention (joint washout/incision and drainage/curettage) was required in 11 patients. The median hospital stay was 27.5 (range 13-63) days; two patients required admission to intensive care. No mortality was reported. CONCLUSION: Melioidosis of the extremities is not uncommon in Brunei Darussalam. It is associated with significant morbidity, and a large number of patients require surgical intervention. Thus, a high index of suspicion is required for early diagnosis and institution of appropriate antibiotic therapy.


Subject(s)
Burkholderia pseudomallei/metabolism , Extremities/microbiology , Melioidosis/diagnosis , Melioidosis/etiology , Adolescent , Adult , Brunei , Female , Hospitalization , Humans , Male , Melioidosis/epidemiology , Melioidosis/microbiology , Middle Aged , Orthopedics/methods , Retrospective Studies , Treatment Outcome
15.
Osteoporos Int ; 20(12): 2055-61, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19436939

ABSTRACT

SUMMARY: Fall risk does not significantly impact on the efficacy of the bisphosphonate clodronate in reducing the incidence of fracture. INTRODUCTION: The debate about the efficacy of skeletal therapies on fracture risk in women at increased risk of falling continues. We determined whether fall risk impeded the efficacy of clodronate to reduce osteoporotic fracture incidence. METHODS: This is a post hoc analysis of a 3-year placebo-controlled study of bisphosphonate clodronate involving 5,212 women aged 75 years or more. At entry, self-reported multiple falls in the previous month and ability to rise from a chair were documented. Their interaction with treatment efficacy was examined using Poisson regression. RESULTS: Oral doses of clodronate at 800 mg daily reduced osteoporotic fracture incidence by 24% (hazard ration (HR) 0.76, 95% confidence interval 0.63-0.93). The efficacy was similar in women with recent multiple falls compared to those without (HR 0.61 vs. 0.77, p value for interaction >0.30) or impaired ability in rising compared to those with no impairment (HR 0.79 vs. 0.74, respectively; p value > 0.30). CONCLUSION: Fall risk does not significantly impact on the anti-fracture efficacy of clodronate. If confirmed with other agents, fall risk may be incorporated into risk assessment tools designed to target skeletal therapies.


Subject(s)
Accidental Falls , Bone Density Conservation Agents/therapeutic use , Clodronic Acid/therapeutic use , Osteoporotic Fractures/prevention & control , Aged , Aged, 80 and over , Algorithms , Bone Density/physiology , Epidemiologic Methods , Female , Femur Neck/physiopathology , Humans , Osteoporosis, Postmenopausal/complications , Osteoporosis, Postmenopausal/physiopathology , Osteoporotic Fractures/etiology , Osteoporotic Fractures/physiopathology , Prognosis , Treatment Outcome
16.
Osteoporos Int ; 20(5): 811-7, 2009 May.
Article in English | MEDLINE | ID: mdl-19002369

ABSTRACT

UNLABELLED: Fracture risk prediction can be enhanced by the concurrent assessment of other clinical risk factors. This study demonstrates that the estimation of an individual's 10-year probability of fracture by the FRAX algorithm identifies patients at high risk of fracture who will respond to bisphosphonate therapy. INTRODUCTION: Treatments for osteoporosis are targeted largely to patients with low bone density (BMD) or a prior fragility fracture. Fracture risk prediction can be enhanced by the concurrent assessment of other clinical risk factors, but it is important to determine whether the risk so identified can be reduced by intervention. We determined the effect of a bisphosphonate on fracture rates when risk was calculated using a new risk algorithm (FRAX). METHODS: Women aged 75 years or more were recruited to a randomised, double-blind controlled trial of 800 mg oral clodronate (Bonefos) daily over 3 years. Baseline clinical risk factors were entered in the FRAX model to compute the 10-year probability of major osteoporotic fractures with or without input of femoral neck BMD. The interaction between fracture probability and treatment efficacy was examined by Poisson regression. RESULTS: In 3,974 women, the interaction between fracture probability and treatment efficacy was significant when probability was assessed without BMD (p = 0.043), but not when BMD was included (p = 0.10). Efficacy was more evident in those deemed at highest risk. For example women lying at the 75th percentile of fracture probability in the absence of BMD (10-year probability 24%) treatment reduced fracture risk by 27% (HR 0.73, 95%CI 0.58-0.92). In those with a fracture probability of 30% (90th percentile), the fracture risk reduction was 38% (HR 0.62, 0.46-0.84). CONCLUSIONS: The estimation of an individual's 10-year probability of fracture by the FRAX algorithm identifies patients at high risk of fracture who will respond to bisphosphonate therapy.


Subject(s)
Algorithms , Bone Density Conservation Agents/therapeutic use , Clodronic Acid/therapeutic use , Fractures, Bone/prevention & control , Osteoporosis, Postmenopausal/drug therapy , Absorptiometry, Photon , Aged , Aged, 80 and over , Bone Density/drug effects , Double-Blind Method , Female , Fractures, Bone/epidemiology , Hip Joint/diagnostic imaging , Humans , Osteoporosis, Postmenopausal/epidemiology , Probability , Risk Assessment , Risk Factors , Treatment Outcome , United Kingdom/epidemiology
17.
J Assoc Physicians India ; 53: 433-6, 2005 May.
Article in English | MEDLINE | ID: mdl-16124350

ABSTRACT

OBJECTIVES: The present study was done to assess knowledge about osteoporosis in learned Indian women, identify their source of knowledge and to study the correlation of level of knowledge with other variables. METHODS: A total of 73 female staff members (average age 44.7 years) of a teaching institute completed the Osteoporosis Questionnaire (OPQ). The mean +/- SD of total score for the sample was 4.1 +/- 4.1 (range -8 to 15; maximum possible score 20). RESULTS: The correct definition of osteoporosis was given by 74%, but there was general lack of awareness in all the areas assessed. There was statistically significant difference in the total score depending on the faculty of education, with staff members from the science faculty having the maximum mean score (p < 0.05). We found no influence of age, menopausal status, previous history of fracture and family history of osteoporosis on the level of knowledge. Media (74%) was the commonest source of knowledge followed by friends (49%) and doctors (25%). CONCLUSIONS: This study highlights the general lack of knowledge about osteoporosis in learned Indian women and also the need for increased involvement of medical professionals in patient education.


Subject(s)
Awareness , Faculty , Health Knowledge, Attitudes, Practice , Osteoporosis , Women/education , Adult , Educational Status , Female , Humans , India , Middle Aged , Risk Factors , Surveys and Questionnaires , Women/psychology
18.
J Orthop Surg (Hong Kong) ; 13(1): 27-33, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15872397

ABSTRACT

PURPOSES: To assess osteoporosis using plain radiography of the calcaneum by studying the performance characteristics of the modified calcaneal index through inter- and intra-observer agreement. To study the correlation of the modified calcaneal index to quantitative ultrasound of the calcaneus and bone mineral density (BMD) of the femoral neck and distal radius. METHODS: Lateral calcaneal radiographs of 252 women who participated in a clinical trial for osteoporosis were reviewed. The BMD of the hip and distal radius was measured and the calcanea were assessed using ultrasound. The calcaneal radiographs were graded by 3 clinicians according to a previously described 5-grade calcaneal index. A modified 3-grade calcaneal index was then developed. RESULTS: The highest scores of intra- and inter-observer reliability of the modified calcaneal index were 0.45 and 0.40, respectively, which were higher than those of the 5-grade calcaneal index. The correlation of the modified calcaneal index with other measures was significant (hip BMD, r=0.31; distal radius BMD, r=0.28; calcaneal speed of sound, r=0.20; broadband ultrasound attenuation, r=0.36) [p<0.005]. There were significant differences in hip BMD, distal radial BMD, calcaneal speed of sound, and broadband ultrasound attenuation between the 3 grades of the modified calcaneal index (Kruskal-Wallis 1-way ANOVA; p<0.0001). CONCLUSION: The modified calcaneal index can be used to measure bone structure and skeletal strength and is a suitable screening tool for osteoporosis in places where advanced approaches to bone-status assessment are not available.


Subject(s)
Calcaneus/diagnostic imaging , Mass Screening/methods , Osteoporosis/diagnostic imaging , Absorptiometry, Photon , Aged , Bone Density , Female , Femur Neck/diagnostic imaging , Humans , Observer Variation , Osteoporosis/diagnosis , Radius/diagnostic imaging , Ultrasonography
20.
Anal Sci ; 19(11): 1477-80, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14640442

ABSTRACT

The electrochemical entrapment of polyaniline (PANI) onto sol-gel derived tetraethylorthosilicate (TEOS) films deposited onto indium-tin-oxide (ITO) coated glass has been utilized for immobilization of lactate dehydrogenase (LDH). The performance of these sol-gel/PANI/LDH electrodes has been investigated as a function of the lactate concentration, applied potential, pH of the medium and interferents. The amperometric response of the electrodes under optimum conditions exhibited a linear relationship from 1 mM to 4 mM. An attempt has been made to extend the linearity up to 10 mM for lactate by coating an external layer of polyvinyl chloride (PVC) over the sol-gel/PANI/LDH electrodes with a correlation coefficient of 0.89. These sol-gel/PANI/LDH electrodes have a response time of about 60 s, a shelf life of about 8 weeks at 0-4 degrees C and have implications in a lactate biosensor.


Subject(s)
Aniline Compounds/chemistry , Biosensing Techniques/methods , Lactic Acid/analysis , Silanes/chemistry , Electrochemistry , Electrodes , Hydrogen-Ion Concentration , L-Lactate Dehydrogenase/chemistry , NAD/chemistry , Phase Transition , Polyvinyl Chloride/chemistry
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