• Mass Spectrometry Letters
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• 제15권1호
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• pp.62-68
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• 2024

The Suspension Trapping (S-Trap) method has been a prominent sample preparation technique since its introduction in 2014. Its capacity to induce protein aggregation using organic solvents has significantly improved protein purification and facilitated peptide identification. However, its full potential for automation has been limited by the lack of a suitable liquid handling system until recently. In this study, we aimed to enhance the automation of S-Trap sample preparation by optimizing the S-Trap digestion process, incorporating triethylammonium bicarbonate (TEAB) and CaCl₂. The utilization of TEAB buffer conditions in this innovative process led to a noteworthy 12% improvement in protein identification. Additionally, through careful observation of various incubation conditions, we streamlined the entire sample preparation workflow into a concise 4 hours timeline, covering reduction, alkylation, and trypsin incubation stages. This refined and expedited automated S-Trap digestion process not only showcased exceptional time efficiency but also improved trypsin digestion, resulting in increased protein identification.

• Mass Spectrometry Letters
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• 제4권2호
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• pp.25-29
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• 2013

Proteomics for biomarker validation needs high throughput instrumentation to analyze huge set of clinical samples for quantitative and reproducible analysis at a minimum time without manual experimental errors. Sample preparation, a vital step in proteomics plays a major role in identification and quantification of proteins from biological samples. Tryptic digestion a major check point in sample preparation for mass spectrometry based proteomics needs to be more accurate with rapid processing time. The present study focuses on establishing a high throughput automated online system for proteolytic digestion and desalting of proteins from biological samples quantitatively and qualitatively in a reproducible manner. The present study compares online protein digestion and desalting of BSA with conventional off-line (in-solution) method and validated for real time sample for reproducibility. Proteins were identified using SEQUEST data base search engine and the data were quantified using IDEALQ software. The present study shows that the online system capable of handling high throughput samples in 96 well formats carries out protein digestion and peptide desalting efficiently in a reproducible and quantitative manner. Label free quantification showed clear increase of peptide quantities with increase in concentration with much linearity compared to off line method. Hence we would like to suggest that inclusion of this online system in proteomic pipeline will be effective in quantification of proteins in comparative proteomics were the quantification is really very crucial.

• 한국연초학회지
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• 제32권2호
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• pp.70-76
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• 2010

A simple and sensitive automatic amino acid analyzer method for the determination of free amino acids in tobacco was described. Sample preparation consisted of a single step of extraction with 0.1 mol HCl at ambient temperature in 60 min by sonication, followed by filtration of an aliquot. Automated amino acid analyzer was used to construct a post-column ninhydrin reaction unit to monitor amino acids separated by liquid chromatography using a series of eluting buffers. By optimization of sample preparation, separation of 19 amino acids was achieved. Limits of quantitation was 0.01 mg/g, coefficients of variation ranged from 0.5 % to 8.9 % and recoveries range from 85 % to 106 %. The method was applied to the analysis of amino acids contents of tobacco leaves in different varieties.

• Computers and Concrete
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• 제5권2호
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• pp.101-116
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• 2008

The microscopic determination of air void characteristics in hardened concrete, defined in EN 480-11 as the linear-traverse method, is an extremely time-consuming and tedious task. Over past decades, several researchers have proposed relatively expensive mechanical automated systems which could replace the human operator in this procedure. Recently, the appearance of new high-resolution flatbed scanners has made it possible for the procedure to be automated in a fully-computerized and thus cost-effective way. The results of our work indicate the high sensitivity of such image analysis automated systems firstly to the quality of sample surface preparation, secondly to the selection of the air void threshold value, and finally to the selection of the probe system. However, it can be concluded that in case of careful validation and the use of the approach which is proposed in the paper, such automated systems can give very good estimate of the air void system parameters, defined in EN 480-11. The amount of time saved by using such a procedure is immense, and there is also the possibility of using alternative stereological methods to assess other, perhaps also important, characteristics of air void system in hardened concrete.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2006년도 추계학술대회
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• pp.65-74
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• 2006

Modem drug discovery requires rapid pharmacokinetic evaluation of chemically diverse compounds for early candidate selection. This demands the development of analytical methods that offer high-throughput of samples. Naturally, liquid chromatography / tandem mass spectrometry (LC-MS/MS) is choice of the analytical method because of its superior sensitivity and selectivity. As a result of the short analysis time(typically 3-5min) by LC-MS/MS, sample preparation has become the rate- determining step in the whole analytical cycle. Consequently tremendous efforts are being made to speed up and automate this step. In a typical automated 96-well SPE(solid-phase extraction) procedure, plasma samples are transferred to the 96-well SPE plate, internal standard and aqueous buffer solutions are added and then vacuum is applied using the robotic liquid handling system. It takes only 20-90 min to process 96 samples by automated SPE and the analyst is physically occupied for only approximately 10 min. Recently, the ultra-high flow rate liquid chromatography (turbulent-flow chromatography)has sparked a huge interest for rapid and direct quantitation of drugs in plasma. There is no sample preparation except for sample aliquotting, internal standard addition and centrifugation. This type of analysis is achieved by using a small diameter column with a large particle size(30-5O ${\mu}$m) and a high flow rate, typically between 3-5 ml/min. Silica-based monolithic HPLC columns contain a novel chromatographic support in which the traditional particulate packing has been replaced with a single, continuous network (monolith) of pcrous silica. The main advantage of such a network is decreased backpressure due to macropores (2 ${\mu}$m) throughout the network. This allows high flow rates, and hence fast analyses that are unattainable with traditional particulate columns. The reduction of particle diameter in HPLC results in increased column efficiency. use of small particles (<2 urn), however, requires p.essu.es beyond the traditional 6,000 psi of conventional pumping devices. Instrumental development in recent years has resulted in pumping devices capable of handling the requirements of columns packed with small particles. The staggered parallel HPLC system consists of four fully independent binary HPLC pumps, a modified auto sampler, and a series of switching and selector valves all controlled by a single computer program. The system improves sample throughput without sacrificing chromatographic separation or data quality. Sample throughput can be increased nearly four-fold without requiring significant changes in current analytical procedures. The process of Bioanalytical Method Validation is required by the FDA to assess and verify the performance of a chronlatographic method prior to its application in sample analysis. The validation should address the selectivity, linearity, accuracy, precision and stability of the method. This presentation will provide all overview of the work required to accomplish a full validation and show how a chromatographic method is suitable for toxirokinetic sample analysis. A liquid chromatography/tandem mass spectrometry (LC-MS/MS) method developed to quantitate drug levels in dog plasma will be used as an example of tile process.

• Journal of Biosystems Engineering
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• 제36권5호
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• pp.326-333
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• 2011

The need for rapid on-site monitoring of hydroponic macronutrients has led to the use of ion-selective electrodes, because of their advantages over spectrophotometric methods, including simple methodology, direct measurement of analyte, sensitivity over a wide concentration range, and low cost. Stability and repeatability of response can be a concern when using multiple ion-selective electrodes to measure concentrations in a series of samples because accuracy might be limited by drifts in electrode potential. A computer-based measurement system could improve accuracy and precision because of both consistent control of sample preparation and easy calibration of sensors. Our goal was to investigate the applicability of a cobalt-based electrode used in conjunction with a laboratory-made automated test stand for quantitative determination of ${PO_4}^-$ in hydroponic solution. Six hydroponic solutions were prepared by diluting highly concentrated paprika hydroponicsolution to provide a concentration range of 1 to 300 ppm $PO_4$-P. A calibration curve relating electrode response to phosphate in paprika hydroponic solution titrated to pH 4 with 0.025M KHP was developed based on the Nikolskii-Eisenman equation with a coefficient of determination ($R^2$) of 0.94. The laboratory-made test stand consisting of three cobalt-based electrodes measured phosphate concentrations similar to those obtained with standard laboratory methods (a regression slope of 0.98 with $R^2$ = 0.80). However, the y intercept was relatively high, 30 ppm, probably due to the relatively large amount of variation present among multiple measurements of the same sample. Further studies on the high variation in EMFs obtained with cobalt electrodes during replicate measurements were required for P estimations comparable to those obtained with standard laboratory instruments.

• 지질공학
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• 제20권3호
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• pp.281-295
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• 2010

새롭게 구축된 자동 흙-함수특성곡선 시험장치는 측정원리가 간단하고 연속적인 측정이 가능하며, 시험자에 의해 발생될 수 있는 오차를 최소화하여 보다 정확한 불포화토의 흙-함수특성곡선을 산정할 수 있다. 본 시험장치는 압력조절장치, 플로우셀, 물저장소, 공기방울트랩, 저울, 시료준비장치, 측정시스템 등으로 구성되어 있다. 공기의 압력은 0-300 kPa범위까지 적용할 수 있으며, 단기간내 시험을 완료할 수 있다. 본 시험장치에서는 건조과정과 습윤과정을 재현할 수 있으며, 측정 자동화 프로그램(SWRC)을 이용하여 건조과정과 습윤과정에 따른 시료내 함수비 변화를 실시간으로 확인할 수 있다. 본 시험기를 이용하여 상대밀도 75%인 주문진 표준사에 대한 건조 및 습윤과정의 체적함수비에 따른 모관흡수력을 측정하였다. 측정결과, 건조 및 습윤과정을 거치는 동안 동일한 체적함수비에서 대한 모관흡수력 값이 다르게 나타나는 이력현상(hysteresis)이 발생하였다. 측정된 결과를 토대로 기존의 Brooks and Corey, van Genuchten 및 Fredlund and Xing 방법을 이용하여 흙-함수특성곡선을 예측하였다. 결정계수를 이용하여 이들 방법에 대한 정확성을 평가한 결과 대상토질조건의 경우 van Genuchten방법이 신뢰성이 가장 높은 것으로 나타났다.

• 대한임상검사과학회지
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• 제56권2호
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• pp.135-146
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• 2024

요검사는 검사실에서 일상적으로 수행되는 기본적인 검사이다. 연구에서 새로운 프로토콜을 포함한 두 가지 수동 현미경검사 방법을 표준화된 chamber 방법과 비교하였다. 시험지검사와 자동 침사물 분석기에서 적혈구 양성 201개와 백혈구 양성인 201개 검체로 구성된 총 402개 검체를 분석 대상으로 선정했다. 적혈구 및 백혈구에 대한 표준화된 chamber 방법과 새로운 프로토콜 방법 간의 상관계수는 모두 r=0.98로, 높은 수준의 상관관계를 나타냈다. 이 두 방법 간의 동일 등급에 대한 쌍별 일치율은 적혈구의 경우 86.1%, 백혈구의 경우 88.6%였으며, 한 등급 차이 내 일치율은 모두 99.5%였다. 반면, 표준화된 chamber 방법과 중·소규모 검사실 방법 간의 일치율은 적혈구의 경우 11.9%, 백혈구의 경우 13.4%로, 동일 등급 일치율이 현저히 낮았고, 한 등급 차이 내 일치율은 각각 67.2%와 74.1%로 나타났다. 급내상관계수 및 Bland-Altman plot을 사용한 분석에서는 새로운 프로토콜이 다른 세 가지 수동 현미경검사 방법에 비해 우수한 일치도를 보인 것으로 확인되었다. 표준화된 chamber 방법과의 높은 상관관계와 일치도를 고려해 볼 때, 새로운 프로토콜 방법을 소변 침사물 표본제작의 표준화된 절차로 권장한다.

• 핵의학기술
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• 제25권2호
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• pp.29-34
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• 2021

핵의학과 검체 접수 환경시스템은 20년 전과 비교하여 보았을 때 크게 달라지지 않은 채 동일한 시스템으로 검체 접수 업무가 이루어지고 있다. 핵의학과 검사 특성상 진단검사의 학과와 달리 검체 용기 자체로 검사가 시행되는 것이 아니라 모검체에서 자검체를 생성하여 검사를 시행하는 시스템이기 때문에 지금까지 큰 변화 없이 이어져 온 것으로 보인다. 본원에서는 이러한 검체 접수 환경시스템을 개선하고자 검체의 뚜껑을 자동으로 제거해 주고 동시에 자동접수가 가능한 decapper 자동화 장비를 도입한 사례와 가접수 시스템 적용 사례에 대해서 소개해 보고자 한다. 본원에서는 2019년 환자의 검체 뚜껑을 자동으로 제거해 주는 장비를 도입하고자 진단검사의학과 응급검사실에서 사용하는 Vacuette ® Unicap Belt Decapper(Greiner bio-one, Austria) 제품을 벤치마킹하여 구매를 시도하였으나 5 ml SST, 8 ml SST 튜브를 사용하는 핵의학과 검체를 처리하려면 2대의 장비가 필요하여 예산과 공간 문제에 부딪혀 구매가 지연되었다. 2020년 1월 국산 decapper 자동화 장비를 대여 받아 검체 검사실 접수 실정에 맞게 지속적인 아이디어 제공과 테스트로 수정 보완하여 2020년 10월 검체 뚜껑을 자동으로 제거해 주는 동시에 자동접수 해주는 decapper 자동화 장비를 도입하게 되었다. 또한 검체 접수 전 단계에서 가접수 시스템을 도입하여 병동과 응급실, 건강증진센터 이송사원이 검체를 갖고 검사실에 도착하면 검체를 셀프로 가접수 하여 빠른 시간 내에 검체 도착 여부를 알릴 수 있도록 개선하였다. Decapper 자동화 장비가 도입되면서 자동으로 검체 뚜껑이 제거되고 접수되는 순간에 다른 업무를 수행할 수 있게 되어 검사자의 업무 효율성을 크게 증대 시킬 수 있었고 검사 소요시간에 영향을 미칠 수 있는 검체 접수 마감시간이 단축되어 검사시작을 10분~20분 정도 단축시킬 수 있는 효과를 볼 수 있었다. 또한 반복된 손목 사용으로 인하여 발생되는 근골격계 질환의 감소로 검사자의 건강장해를 예방할 수 있었다. 가접수 시스템을 설치한 후 병동에서는 빠른 퇴원이 가능해졌고 검체 도착 여부를 묻는 불필요한 전화문의 횟수도 감소하게 되었다. 대부분의 핵의학과 검체 검사실은 소규모의 인력으로 운영되고 있는 것이 현실이다. 최소 인력으로 검체 검사와 검체 접수 업무를 동시에 수행해야 되는 소규모 기관에서는 decapper 자동화 장비와 가접수 시스템을 도입 시 업무를 보다 원활히 수행하는데 도움이 될 수 있을 것으로 사료된다.

• 한국동물위생학회지
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• 제43권3호
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• pp.147-154
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• 2020

Standard samples were prepared for this study, and applied for BactoScan^TM and BactoCount^TM in order for quality control evaluation for total bacterial count in raw milk. Accordingly, the preparation of two lots of standard samples for quality control were lyophilized, which contain Lactobacillus lactis. The standard samples were prepared into three different levels of bacterial counts, those were Low 30,000~40,000, Medium 70,000~90,000, High 150,000~220,000 CFU/mL, respectively. Then, the proficiency tests were performed in total 19 laboratories for measuring total bacterial counts. The total bacterial counts in the standard samples showed 37~42, 82~105, 214~240 CFU/mL in the first lot, and it showed 30~36, 67~75, 131~163 CFU/mL in the second lot in low, medium and high levels, respectively. Based on these results, the absolute values of z-scores of six standard samples in 18 laboratories were ≤2, which means the samples are satisfactory. However, z-score in one laboratory was ≤3, which means the sample is questionable. Using two standard samples, the correlation between BactoScan^TM and BactoCount^TM was 0.9982, which means the results of total bacterial count measurement of both equipment were equivalent. Therefore, the standard samples manufactured in this study for quality control of total bacterial count using BactoScan^TM and BactoCount^TM in the raw milk could be applied to proficiency tests.