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1.
Environ Int ; 163: 107198, 2022 05.
Article in English | MEDLINE | ID: mdl-35447437

ABSTRACT

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are persistent substances with surfactant and repellent properties. Municipal drinking water contaminated with PFAS had been distributed for decades to one third of households in Ronneby, Sweden. The source was firefighting foam used in a nearby airfield since the mid-1980s. Clean water was provided from December 16, 2013. AIMS: The purpose was to estimate serum half-lives and their determinants in the study population for different PFAS. METHODS: Up to ten blood samples were collected between 2014 and 2018 from 114 participants (age 4-84 years at entry, 53% female). 19 PFAS were analysed. Linear mixed models were used to estimate the half-lives. RESULTS: Eight PFAS were increased in Ronneby: perfluorooctanoic acid (PFOA), perfluoropentane sulfonate (PFPeS), perfluorohexane sulfonate (PFHxS), perfluoroheptane sulfonate (PFHpS), linear perfluorooctane sulfonate (L-PFOS) and three branched perfluorooctane sulfonates (1 m-PFOS, 3/4/5m-PFOS and 2/6m-PFOS). The mean estimated half-lives (in years) were 0.94 (95 %CI 0.86-1.02) for PFPeS, 2.47 (2.27-2.7) for PFOA, 2.67 (2.51-2.85) for 2/6m-PFOS, 2.73 (2.55-2.92) for L-PFOS, 3.43 (3.19-3.71) for 3/4/5m-PFOS, 4.52 (4.14-4.99) for PFHxS, 4.55 (4.14-5.06) for PFHpS, and 5.01 (4.56-5.55) for 1 m-PFOS. The most important determinants of a shorter half-life were young age, and better kidney function measured by estimated glomerular filtration rate and ratio of paired urine and serum PFAS levels, followed by female sex during their fertile period aged 15-50. Markers of gut inflammation and reduced permeability i.e. zonulin and calprotectin were also possibly associated with shorter half-life. The results also suggested a time-dependent PFAS elimination process, with more rapid elimination in the first year after the end of exposure. CONCLUSION: The half-life estimates are in line with past estimates for some PFAS such as PFOA, and the novel results for different PFOS isomers. These results provide observational support for elimination routes - renal, fecal and maternal.


Subject(s)
Alkanesulfonic Acids , Drinking Water , Environmental Pollutants , Fluorocarbons , Water Pollutants, Chemical , Alkanesulfonates , Drinking Water/analysis , Environmental Pollutants/analysis , Female , Half-Life , Humans , Male , Sweden , Water Pollutants, Chemical/analysis
3.
Environ Health Perspect ; 128(7): 77004, 2020 07.
Article in English | MEDLINE | ID: mdl-32648786

ABSTRACT

BACKGROUND: Firefighting foam-contaminated ground water, which contains high levels of perfluoroalkyl substances (PFAS), is frequently found around airports. In 2018 it was detected that employees at a municipal airport in northern Sweden had been exposed to high levels of short-chain PFAS along with legacy PFAS (i.e., PFOA, PFHxS, and PFOS) through drinking water. OBJECTIVES: In this study, we aimed to describe the PFAS profile in drinking water and biological samples (paired serum and urine) and to estimate serum half-lives of the short-chain PFAS together with legacy PFAS. METHODS: Within 2 weeks after provision of clean water, blood sampling was performed in all 26 airport employees. Seventeen of them were then followed up monthly for 5 months. PFHxA, PFHpA, PFBS, PFPeS, and PFHpS together with legacy PFAS in water and biological samples were quantified using LC/MS/MS. Half-lives were estimated by assuming one compartment, first-order elimination kinetics. RESULTS: The proportions of PFHxA, PFHpA, and PFBS were higher in drinking water than in serum. The opposite was found for PFHxS and PFOS. The legacy PFAS accounted for about 50% of total PFAS in drinking water and 90% in serum. Urinary PFAS levels were very low compared with serum. PFBS showed the shortest half-life {average 44 d [95% confidence interval (CI): 37, 55 d]}, followed by PFHpA [62 d (95% CI: 51, 80 d)]. PFPeS and PFHpS showed average half-lives as 0.63 and 1.46 y, respectively. Branched PFOS isomers had average half-lives ranging from 1.05 to 1.26 y for different isomers. PFOA, PFHxS, and linear PFOS isomers showed average half-lives of 1.77, 2.87, and 2.93 y, respectively. DISCUSSION: A general pattern of increasing half-lives with increasing chain length was observed. Branched PFOS isomers had shorter half-lives than linear PFOS isomers. https://doi.org/10.1289/EHP6785.


Subject(s)
Drinking Water/chemistry , Environmental Exposure/statistics & numerical data , Environmental Monitoring , Fluorocarbons/blood , Water Pollutants, Chemical/analysis , Aerosols , Alkanesulfonic Acids/analysis , Caprylates/analysis , Flame Retardants/analysis , Groundwater/chemistry , Half-Life , Humans , Sweden
4.
Int J Qual Stud Health Well-being ; 14(1): 1647402, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31349764

ABSTRACT

In order to describe how women with osteoporosis strive to maintain daily life we interviewed 11 women using a reflective lifeworld approach based on phenomenological analysis. Osteoporosis is a major public health concern in the Western world, and is predominant among women. Our findings indicated that meanings of striving to maintain daily life imply a belief in oneself and one's own capabilities. The women expressly speak out for themselves as a way of finding reconciliation without giving in to the illness. Women with osteoporosis expect to gain support early in the course of their illness. They require advice on how to manage the disease as well as support for striving to maintain daily living. Therefore, it is crucial that the women not only are given information about the disease. Equally important is to establish continuity in healthcare encounters, and that health care offers support founded in the women's lived experiences with focus on their capacities.


Subject(s)
Activities of Daily Living , Osteoporosis/psychology , Aged , Female , Humans , Interviews as Topic , Middle Aged , Qualitative Research
5.
Intensive Crit Care Nurs ; 54: 1-6, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31351691

ABSTRACT

OBJECTIVES: In an effort to strengthen health care professionals' ability to anticipate and address multiple trauma patients' needs, this study aims to explore the experience of suffering from multiple trauma. DESIGN: This is a qualitative descriptive study. Nine interviews were analysed using content analysis. SETTING: The study included patients who had been registered in the Swedish Intensive Care registry [SIR] due to suffering multiple trauma. FINDINGS: The analysis revealed one theme, A detour in life, based on three sub-themes: (a) Feeling lost and not knowing what to expect, (b) Striving to get life back on track and (c) Dealing with 'dead ends' during rehabilitation. The theme showed that those who suffered multiple trauma did not know what to expect of their recovery and they expressed experiencing a lack of understanding and guidance from healthcare professionals. As it was important to focus on the present and find ways to move on in life, they sought for other ways to find direction in matters of rehabilitation and care. CONCLUSIONS: A shared understanding is essential in order to define a person's needs. By setting short-term goals and improving documentation, healthcare professionals across the trauma recovery continuum could more easily gain insight of their patients' needs and address them with supportive guidance.


Subject(s)
Multiple Trauma/complications , Stress, Psychological/etiology , Humans , Interviews as Topic/methods , Multiple Trauma/psychology , Qualitative Research , Stress, Psychological/psychology , Sweden
6.
Circulation ; 138(24): 2754-2762, 2018 12 11.
Article in English | MEDLINE | ID: mdl-30767504

ABSTRACT

Background: In the DETO2X-AMI trial (Determination of the Role of Oxygen in Suspected Acute Myocardial Infarction), we compared supplemental oxygen with ambient air in normoxemic patients presenting with suspected myocardial infarction and found no significant survival benefit at 1 year. However, important secondary end points were not yet available. We now report the prespecified secondary end points cardiovascular death and the composite of all-cause death and hospitalization for heart failure. Methods: In this pragmatic, registry-based randomized clinical trial, we used a nationwide quality registry for coronary care for trial procedures and evaluated end points through the Swedish population registry (mortality), the Swedish inpatient registry (heart failure), and cause of death registry (cardiovascular death). Patients with suspected acute myocardial infarction and oxygen saturation of ≥90% were randomly assigned to receive either supplemental oxygen at 6 L/min for 6 to 12 hours delivered by open face mask or ambient air. Results: A total of 6629 patients were enrolled. Acute heart failure treatment, left ventricular systolic function assessed by echocardiography, and infarct size measured by high-sensitive cardiac troponin T were similar in the 2 groups during the hospitalization period. All-cause death or hospitalization for heart failure within 1 year after randomization occurred in 8.0% of patients assigned to oxygen and in 7.9% of patients assigned to ambient air (hazard ratio, 0.99; 95% CI, 0.84­1.18; P=0.92). During long-term follow-up (median [range], 2.1 [1.0­3.7] years), the composite end point occurred in 11.2% of patients assigned to oxygen and in 10.8% of patients assigned to ambient air (hazard ratio, 1.02; 95% CI, 0.88­1.17; P=0.84), and cardiovascular death occurred in 5.2% of patients assigned to oxygen and in 4.8% assigned to ambient air (hazard ratio, 1.07; 95% CI, 0.87­1.33; P=0.52). The results were consistent across all predefined subgroups. Conclusions: Routine use of supplemental oxygen in normoxemic patients with suspected myocardial infarction was not found to reduce the composite of all-cause mortality and hospitalization for heart failure, or cardiovascular death within 1 year or during long-term follow-up. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01787110.


Subject(s)
Heart Failure/etiology , Hospitalization/statistics & numerical data , Myocardial Infarction/therapy , Oxygen Inhalation Therapy/adverse effects , Acute Disease , Aged , Female , Heart Failure/mortality , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Myocardial Infarction/pathology , Proportional Hazards Models , Registries , Risk Factors , Treatment Outcome
7.
Int Emerg Nurs ; 32: 34-38, 2017 May.
Article in English | MEDLINE | ID: mdl-27697403

ABSTRACT

INTRODUCTION: When emergency medical services (EMS) are needed, the choice of transport depends on several factors. These may include the patient's medical condition, transport accessibility to the accident site and the receiving hospital's resources. Emergency care research is advancing, but little is known about the patient's perspective of helicopter emergency medical services (HEMS). AIM: The aim of this study was to describe trauma patients' experiences of HEMS. METHOD: Thirteen persons (ages 21-76) were interviewed using an interview guide. Data were analyzed using qualitative content analysis. FINDINGS: The analysis resulted in three themes: Being distraught and dazed by the event - patients experienced shock and tension, as well as feelings of curiosity and excitement. Being comforted by the caregivers - as the caregivers were present and attentive, they had no need for relatives in the helicopter. Being safe in a restricted environment - the participants' injuries were taken seriously and the caregivers displayed effective teamwork. CONCLUSION: For trauma patients to be taken seriously and treated as 'worst cases' enables them to trust their caregivers and 'hand themselves over' to their care. HEMS provide additional advantageous circumstances, such as being the sole patient and having proximity to a small, professional team.


Subject(s)
Aircraft , Empathy , Patient Satisfaction , Patients/psychology , Wounds and Injuries/psychology , Adult , Aged , Female , Humans , Life Change Events , Male , Middle Aged , Qualitative Research , Sweden , Wounds and Injuries/complications
8.
Br J Community Nurs ; 21(11): 563-567, 2016 Nov 02.
Article in English | MEDLINE | ID: mdl-27809585

ABSTRACT

The aim of this study was to elucidate meanings of balance in everyday life for people with long-term illnesses living at home. People living with long-term illnesses are in need of help and support to manage their daily lives. Twelve adults with extensive needs for help and support were interviewed. A phenomenological hermeneutic interpretation was used to analyse the interview texts. The findings show that balance in everyday life for people with long-term illnesses means striving for independence through care and support in their surroundings. It was also important to be able to choose how their lives would be and to be with others who listened and understood them for who they are. By building a relationship with patients at an early stage of their illnesses, nursing staff have an opportunity to understand what people who are living at home with long-term illnesses need in order to achieve balance in their everyday lives.


Subject(s)
Activities of Daily Living/psychology , Chronic Disease/psychology , Independent Living/psychology , Quality of Life , Adult , Aged , Diabetes Complications/psychology , Diabetes Mellitus/psychology , Female , Humans , Hydrocephalus/complications , Hydrocephalus/psychology , Male , Middle Aged , Multiple Sclerosis/psychology , Qualitative Research , Spinal Cord Injuries/psychology , Spinal Dysraphism/complications , Spinal Dysraphism/psychology , Stroke/psychology
9.
Intensive Crit Care Nurs ; 36: 58-65, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27173952

ABSTRACT

SETTINGS AND OBJECTIVES: A midsize hospital in the north of Sweden with a high-tech intensive care unit and space for up to 10 patients, with an attached postoperative ward for up to 15 patients. The wards are manned by critical care nurses who are also responsible for carrying a trauma pager. When the alarm goes off, the critical care nurse leaves her/his duties and joins a trauma team. The aim of the study was to describe critical care nurse's experiences of nursing patients suffering from trauma. METHOD: A qualitative descriptive design was used. Data were collected through four focus group discussions with 15 critical care nurses analysed using qualitative content analysis. FINDINGS: One theme: Preparing for the unexpected with four subthemes: (1) Feeling competent, but sometimes inadequate; (2) Feeling unsatisfied with the care environment; (3) Feeling satisfied with well-functioning communication; and (4) Feeling a need to reflect when affected. CONCLUSIONS: Nursing trauma patients require critical care nurses to be prepared for the unexpected. Two aspects of trauma care must be improved in order to fully address the challenges it poses: First, formal preparation and adequate resources must be invested to ensure delivery of quality trauma care. Secondly, follow-ups are needed to evaluate care measures and to give members of the trauma team the opportunity to address feelings of distress or concern.


Subject(s)
Attitude of Health Personnel , Nurse-Patient Relations , Nurses/psychology , Wounds and Injuries/psychology , Adult , Female , Focus Groups , Humans , Intensive Care Units/organization & administration , Male , Middle Aged , Patients/psychology , Qualitative Research , Sweden
10.
Article in English | MEDLINE | ID: mdl-26489404

ABSTRACT

We conducted a qualitative inquiry to describe the meanings of feeling well as experienced by women with Parkinson's disease. Nine women were interviewed and we analysed the interviews using a reflective lifeworld approach based on phenomenological epistemology. We present the analysis as five constituents: the body as unnoticed; being able to move on; feeling joy by being connected; finding peace and harmony; and being the director of one's own life. Our findings can be used to understand and promote well-being among women with Parkinson's disease. In care meetings, knowledge about the lived and experienced health processes supports the women's striving to not let illness dominate their experience of daily life.


Subject(s)
Attitude to Health , Happiness , Parkinson Disease/psychology , Quality of Life , Activities of Daily Living , Aged , Delivery of Health Care , Female , Humans , Knowledge , Mental Health , Middle Aged , Qualitative Research , Self Efficacy , Social Support
11.
Adv Biochem Eng Biotechnol ; 150: 167-82, 2015.
Article in English | MEDLINE | ID: mdl-25761825

ABSTRACT

The crossreactivity of molecularly imprinted polymers (MIPs) and its practical implications are discussed. Screening of MIP libraries is presented as a fasttrack route to discovery of resins selective towards new targets, exploiting the fact that MIPs imprinted with one type of template molecule also show recognition to related and sometimes also to apparently unrelated molecules. Several examples from our own and others' studies are presented that illustrate this crossreactivity and the pattern of recognition is discussed for selected examples.


Subject(s)
Molecular Imprinting/methods , Polymers/chemistry , Polymers/chemical synthesis
12.
Int J Telemed Appl ; 2013: 461829, 2013.
Article in English | MEDLINE | ID: mdl-23690763

ABSTRACT

Introduction. Information and communication technology (ICT) are becoming a natural part in healthcare both for delivering and giving accessibility to healthcare for people with chronic illness living at home. Aim. The aim was to review existing studies describing the use of ICT in home care for communication between patients, family members, and healthcare professionals. Methods. A review of studies was conducted that identified 1,276 studies. A selection process and quality appraisal were conducted, which finally resulted in 107 studies. Results. The general results offer an overview of characteristics of studies describing the use of ICT applications in home care and are summarized in areas including study approach, quality appraisal, publications data, terminology used for defining the technology, and disease diagnosis. The specific results describe how communication with ICT was performed in home care and the benefits and drawbacks with the use of ICT. Results were predominated by positive responses in the use of ICT. Conclusion. The use of ICT applications in home care is an expanding research area, with a variety of ICT tools used that could increase accessibility to home care. Using ICT can lead to people living with chronic illnesses gaining control of their illness that promotes self-care.

13.
Scand J Caring Sci ; 24(2): 259-65, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20030770

ABSTRACT

The aim of this case study was to describe two District Nurses' (DN) experiences of using information and communication technology (ICT) to communicate with chronically ill people in their homes. An electronic messaging program via computers and mobile phones with an Internet connection was used, enabling DNs and the ill people to exchange messages to and from anywhere. The program comprised different virtual rooms, and communication was via text messages. The DNs in this study used the program two to four times each week from November 2003 to March 2004. Semi-structured interviews were performed before, during and after the implementation of the new technology and were analysed using thematic content analysis. The results showed that the DNs felt that the technology increased accessibility to nursing care through a more direct communication with the ill person meaning that a more trusting relationship could be created. The DNs also experienced that the use of ICT saved working time. This study indicates that the use of ICT for communication allowed the DN to better support a chronically ill person at home leading to improved home nursing care. This method of communication cannot replace physical presence, but can be seen as a complement to nursing care at home.


Subject(s)
Chronic Disease/nursing , Communication , Information Services , Nurses/psychology , Humans , Security Measures , Sweden
14.
Anal Bioanal Chem ; 394(7): 1977-84, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19543714

ABSTRACT

We present a novel method for investigating subsite-substrate interactions of glycoside hydrolases and the determination of the oligosaccharide cleavage point based on the analysis of the hydrolysis products produced in the presence of (18)O-labelled water. Conventional techniques for such determination of the hydrolysis pattern call for the chemical modification of the substrate, whereas the method presented makes it possible to use natural substrates, utilising the selectivity and sensitivity of mass spectrometry. This method is very useful for the detection and analysis of enzyme-catalysed hydrolysis, provided that the conditions are chosen where (18)O incorporation without the presence of the enzyme is absent or undetectable. Such conditions were found and used in incubations of cellopentaose with the well-characterised endoglucanase Cel5A from Bacillus agaradhaerens. We were able to confirm that the preferred glycoside bond to be hydrolysed is the third one counting from the non-reducing end of the cellopentaose. Thus, cellopentaose prefers to bind from the -3 to the +2 subsites, which is in accordance with published crystallographic data. The main advantage of the method presented is that there is no need for a priori chemical modification/labelling of oligosaccharide substrates, which are processes that can disturb the enzyme-substrate interaction. From (18)O incorporation we could demonstrate that the enzyme also has an oxygen-exchange activity on cellotriose and cellobiose. This is in agreement with the mechanism for transglycosylation and indicates that it is possible for the enzyme to perform such reactions.


Subject(s)
Cellulase/metabolism , Oligosaccharides/analysis , Spectrometry, Mass, Electrospray Ionization/methods , Water/chemistry , Bacillus/enzymology , Biocatalysis , Cellulase/chemistry , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Hydrolysis , Oxygen Isotopes , Sensitivity and Specificity
15.
Open Nurs J ; 2: 68-72, 2008.
Article in English | MEDLINE | ID: mdl-19319223

ABSTRACT

The use of information and communication technology has increased in the society, and can be useful in nursing care. The aim of this study was to describe district nurses' attitudes regarding the implementation of information and communication technology in home nursing. The first and third authors performed five focus group discussions with 19 district nurses' from five primary healthcare centres in northern Sweden. During the focus group discussions, the following topics were discussed: the current and future use of information and communication technology in home nursing; expectations, advantages, disadvantages and hindrances in the use of information and communication technology in home nursing; and the use of information and communication technology from an ethical perspective. The transcribed focus group discussions were analysed using qualitative content analysis. The results showed that district nurses' attitudes were positive regarding the use of information and communication technology in their work. They also asked for possibilities to influence the design and its introduction. However, the use of information and communication technology in home nursing can be described as a complement to communication that could not replace human physical encounters. Improvements and risks, as well as the importance of physical presence in home nursing were considered vital. The results revealed that the use of information and communication technology requires changes in the district nurses' work situation.

16.
Anal Bioanal Chem ; 385(8): 1421-9, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16804672

ABSTRACT

In this work, a real-time sampling/analytical method for on-line measurements of two newly discovered cyclomaltodextrinases (CDases) has been developed and evaluated. This novel methodology not only allows the final products to be investigated, but it also reveals enzyme-specific differences in the degradation pathways during the hydrolysis of different substrates, which is a great advantage in the important tasks of investigating the mechanisms of and classifying new hydrolases, and is an advantage that conventional techniques cannot offer. Two different enzymes, one CDase from Laceyella sacchari (LsCda13) and one from Anoxybacillus flavithermus (AfCda13), were investigated during the hydrolysis of alpha-, beta- and gamma-cyclodextrin, and the hydrolysis products were sampled via a microdialysis probe and injected on-line every 30 min into a high-performance anion exchange chromatography system equipped with a pulsed amperometric detector (HPAEC-PAD), where they were identified. The enzymes yielded the same end-products, maltose and glucose, in an approximate molar ratio of 2:1, but they exhibited distinctly different patterns of intermediate product formation before reaching the end-point. LsCda13 had a more random distribution of the intermediate products, whereas AfCda13 showed the distinct intermediate production of maltotriose, which in some cases accumulated.


Subject(s)
Chromatography, High Pressure Liquid/methods , Chromatography, Ion Exchange/methods , Glycoside Hydrolases/metabolism , Microdialysis/methods , Anion Exchange Resins/chemistry , Buffers , Cyclodextrins/metabolism , Hydrolysis
17.
J Telemed Telecare ; 12(4): 198-202, 2006.
Article in English | MEDLINE | ID: mdl-16774702

ABSTRACT

We studied the experiences of two people with serious chronic illness who used information and communication technology (ICT) to communicate with their district nurse. The study was a qualitative case study. The intervention was performed using an electronic messaging program. The program was accessible to any computer with an Internet connection. The programme consisted of different virtual rooms, where people could communicate using text messages. The participants used the program 2-4 times each week from the beginning of November 2003 to February 2004. Semistructured interviews were performed before, during and after the intervention and were analysed using thematic content analysis. The results showed that the participants' communication with the district nurse was improved because of easy accessibility and that they felt increased security. They also felt there were fewer limitations and that their everyday life was improved, which can also be seen as an improvement in care.


Subject(s)
Chronic Disease/nursing , Telecommunications , Disabled Persons/psychology , Humans , Internet , Nurse-Patient Relations , Quality of Life
18.
Anal Chem ; 77(10): 3284-91, 2005 May 15.
Article in English | MEDLINE | ID: mdl-15889920

ABSTRACT

Microchip immobilized enzyme reactors (microIMERs) with immobilized endoglucanases were applied for the hydrolysis of methyl cellulose (MC). MCs of various molecular weights were hydrolyzed using two microIMERs containing immobilized celloendoglucanase Cel 5A from Bacillus agaradhaerens (BaCel 5A) connected in series. Hydrolysis by the microIMER could be confirmed from the average molar masses and molar mass distributions measured by size exclusion chromatography (SEC) with online multiangle light scattering and refractive index detection. Methylated cellooligosaccharides with degrees of polymerization (DP) between 1 and 6 formed during hydrolysis were analyzed by direct infusion electrospray ionization ion-trap mass spectrometry (ESI-ITMS). Mass spectra of microIMER- and batch-hydrolyzed samples were compared and no significant differences were found, indicating that microIMER hydrolysis was as efficient as conventional batch hydrolysis. A fast and automated hydrolysis with online MS detection was achieved by connecting the microIMER to high-performance liquid chromatography and ESI-ITMS. This online separation reduced the relative intensities of interfering signals and increased the signal-to-noise ratios in MS. The microIMER hydrolysates were also subjected to SEC interfaced with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. With this technique, oligomers with DP 3-30 could be detected. The hydrolysis by the microIMER was performed within 60 min, i.e. significantly faster compared with batch hydrolysis usually performed for at least 24 h. The microIMER also allowed hydrolysis after 10 days of continuous use. The method presented in this work offers new approaches for the analysis of derivatized cellulose and provides the possibility of convenient online, fast, and more versatile analysis compared with the traditional batch method.


Subject(s)
Cellulase/metabolism , Enzymes, Immobilized , Methylcellulose/metabolism , Microchip Analytical Procedures , Bacillus/enzymology , Cellulase/isolation & purification , Chromatography, Gel , Chromatography, High Pressure Liquid , Hydrolysis , Methylcellulose/chemistry , Molecular Weight , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Time Factors
19.
J Chromatogr A ; 1029(1-2): 87-95, 2004 Mar 12.
Article in English | MEDLINE | ID: mdl-15032353

ABSTRACT

A series of celloendoglucanases: Bacillus agaradhaerens Cel 5a, Humicola insolens Cel 5a, H. insolens Cel 7b, H. insolens Cel 45a, Trichoderma reesei Cel 7b, and T. reesei Cel 45a were used to hydrolyse carboxymethylcellulose (CMC) and the hydrolysis products were investigated with a novel liquid chromatography-mass spectrometry (LC-MS) method. Separation was achieved using a graphitised carbon chromatographic column which allowed the use of electrospay compatible eluents. Analysis of the compounds produced during enzyme hydrolysis of CMC is used to understand enzyme selectivities and substitution pattern of CMC. Conventional high-performance anion-exchange chromatography (HPAEC)-pulsed amperometric detection (PAD), size-exclusion chromatography (SEC)-refractive index (RI) detection, and reducing end analysis are also used to analyse enzyme-hydrolysed CMC. The LC-MS method presented allows for a more detailed investigation of hydrolysis products, which facilitates characterisation of both enzymes and substrates.


Subject(s)
Carboxymethylcellulose Sodium/metabolism , Chromatography, Ion Exchange/methods , Enzymes/metabolism , Mass Spectrometry/methods , Hydrolysis , Substrate Specificity
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