What are the Differences between GC and HPLC?
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manbetx官方and高效液相色谱是学术和工业实验室都有巨大的流行性的分离技术。高效液相色谱已经有利于覆盖药品，食品，生命科学和聚合物的应用中manbetx官方在石油和石化工业，口味和香水和环境空气监测方面具有重要应用。在你的脑海中提出的一般问题是我们的HPLC和GC如何彼此不同，而且因素决定了一个对另一个的因素。
移动阶段
As the name suggests High Performance Liquid Chromatography uses a liquid mobile phase and gas chromatography uses a gas as the carrier. Liquids are generally mixtures of solvents of compatible polarities whereas in gas chromatography themobile phaseis a single high purity gas.
Operating temperature
HPLC.separations are mostly carried out at ambient temperatures whereas Gas Chromatography separations are carried out at elevated temperatures which can be held at a constant value (isothermal) or variable as decided by the temperature program.新包装have extended temperature limits of High Performance Liquid Chromatography operation as well.
化合物的性质
manbetx官方气相色谱分离主要是在分子量上的化合物上进行，其分子量高达几百。这些化合物对其挥发性的差异分开，在高温下保持稳定。在HPLC上分离的另一种手中的化合物具有较高的分子量，从几百至数百万到大型聚合物和生物分子。这些化合物可以仅在室温下分析，因为在升高的温度下，它们倾向于降解。
Column Dimensions
液体uids used as carrier in HPLC generally have higher viscosity in comparison to gases used in Gas Chromatography. This results in increased column back pressures in HPLC. It is for this reason that High Performance Liquid Chromatography columns are much shorter and have wider diameters in comparison to GC columns which can be much longer and narrower. Increased column length improves resolution between closely spaced peaks. As the trend is towards faster analysis columns used for HPLC are as short as 1 cm in length.
Column Packings
与气体相比，柱填料具有更大的液体流动性。气体还具有比液体的固体载体的更高渗透性。保留模式HPLC.columns depends on polarity differences or molecular sizes whereas GC separations are based on differences in volatilities of compounds
Detection principles
HPLC.detection is commonly based on nondestructive detection such as UV, RI, photodiode array detectors, conductivity and laser detection. On the other hand Gas Chromatography detection is based largely on destructive principles such as a FID, NPD and FPD. Mass spectrometry detectors common to both LC and GC are destructive in nature.
Cost of operation
与用于GC分析的气体相比，HPLC溶剂昂贵。除溶剂成本外，由于泵和柱中的高压力，高效液相色谱系统的维护成本也更高。GC分析相比较低，维护成本较低。
HPLC和GC都是通用的，有助于增加应用范围。串联技术，如LC - MS - MS和GC - MS - MS扩大了对新的检测前沿的检测限制，自动化也有助于提高实验室吞吐量。
请分享您的经验并提供有价值的评论。
亲爱的Deepak Bhanot博士
You have wonderfully explained the differences between GC & HPLC. I used to read your articles with great Interest & wants you to add articles on Advanced gas chromatography & its techniques. I wish if you can throw some light on operation of switching valves, Column back flush, column used in this techniques ( Ex..RGA, NGA..etc…) in Petroleum Industry.
Thanks for all your articles………
Regards
Girish Kulkarni
Dear Girish,
非常感谢您的令人鼓舞的评论。GC上的高级级别计划在管道中，应在今年晚些时候提供，并将涵盖您建议的一些主题。
你好Deepak Sir ..
Thanks a lot for sharing your valuable knowledge to who wants to learn about Chromatography operations like me.. And with your information now (not only me) I have known the difference between GC & HPLC.
非常感谢您…。
Best Regards
K.Anjireddy
非常感谢您的鼓励。我总是试图以简单的语言解释概念，这很容易被一个和全部理解。
Thanks for en lighting. I want to analysis Amino Acid profile of fish feed. Could you please suggest best instrument for the same.
Regards
Hi, AA analysis in food is mostly done on HPLC with florescence detector.
Many thanks for sharing ur knowledge and get information about the distinguish between GC and HPLC clearly.
亲爱的Deepak Bhanot博士那
Good day. Thanks for the wonderful explanation regarding the difference of both methods. Would like to clarify, in you context you did mentioned about volatilizes is the focus of GC. In this point of view, juices extraction will not be suit well with GC method? Would you mind to share with me some articles regarding GC or LC for extract crude. Thanks.
嗨,GC可以用于挥发组分a juice though the juice itself is not volatile. what are you trying to analyse in the juice?
你好Deepak Bhanot博士，
Thank you for the clear and detailed explanation of HPLC (liquid) versus GC (gas). I am an old-time Medical Technologist that started when atomic absorption with a graphic furnace was advanced.
I am interested in knowing if, for a given molecule/analyte, there is a preferred method of measurement. You mentioned variables such as operating temperature, nature of the compound (analyte) measured, detection by either conservative methods (UV, RI, PhotoDiodeArray) or destructive methods (FID, NPD, FPD – what do these acronyms stand for?).
因此，如果我们试图比较给定的化合物/分析物（可能Cefazolin）和HPLC是优选的分离方法，而GC：1）由于化合物的性质，则是有优选的方法（LC与GC）;2）如果存在，例如LC，则有有优选的检测方法（UV，RI，光电二极管阵列检测器，电导率和激光检测）吗？或者，对于测量的量（例如，Mg / L范围内的患者血清样品中的Cefazolin的治疗水平），是标准/校准器如此精确的（可能是重量测量），即确切的检测方法（PDA或串联MS）在报告的价值中没有巨大差异？或者，可能是因为化合物的性质，仅使用LC，并且仅用串联质谱检测为例。
My goal is to compare – in this case – serum/plasma antibiotic levels (but it could be any compound) and want to know HOW much difference the type of chromatography (GC or LC) or the final detection method (UV, RI, PDA) really makes in reporting the value. Perhaps based on your description of the SIZE of the compound, let’s say LC is the preferred method. Then, for different labs that use MS or PDA or UV as the final detector, will there be a significant difference in their values, or will they be comparable? I do not have access to any proficiency surveys, but my guess is that based on the compound, there are a limited number of commonly used ways to separate and detect that compound, and, I am hoping the detection method is NOT a large variable. Further, for DIFFERENT manufacturers that use the same separation/detection method, do the INSTRUMENTS make a large difference in the final value? Again, a proficiency would likely show this clearly.
I hope to learn more from you about how comparable assayed values are for the same compound, using different separation/detection methods.
Again, my sincerest thanks for an enlightening article.
mike toyoshima
嗨迈克
First of all thanks for the encouraging comments.The acronyms referred by you relate to detectors for Gas Chromatography.
FID- Flame ionization detector, NPD-Nitrogen Phosphorus detector.FPD- Flame photometric detector.The query raised by you is mainly a method development issue. You will be fortunate if you come across a standard operating procedure based on a validated method using a technique with the right choice of technique combined with a suitable column and detector. In absence of any such method you can develop your own in-house method depending on availability of resources. However, for proficiency level testing in different laboratories there has to be the same method of analysis using identical set of conditions
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in delicious. And certainly, thank you in your effort!
Sir your explaination was very clear and precise thank u for sharing your knowledge
But tell me can i use this comparison in my examination , the question which asked in past paper is .how can you compare GC with HPLC? Please tell me?
Yes but do cover all the points.
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非常感谢您的解释。
I’m quite new to this topic. So, can you explain why we use hplc instead of gcms to analyse antibiotic?
好答案。但是如何安排两个系统的文具面，以便适合我的分析。
Columns usually come pre-packed both for GC and HPLC .Both phases will not be same. You have to refer to supplier catalogs of columns or also refer to applications in research journals to arrive at your choice of suitable columns.
Thank you so much for this clear difference. Everyone who read this, must encourage you for this amazing work
Nice and Informative post, thank you such a nice sharing we can hope find more from you like this topic, thanks again
感谢您在阅读您的帖子后确实帮助我的这些文章，我必须说你正在做好工作。你在这个话题中表现了一个很棒的过程！
You have informative explained differences between gas chromatography and hplc thanks for sharing valuable information with all world
Hi, I am slowly understanding some of these systems under the chromatography umbrella. If my research is correct, HPLC was one, or the first, system to test water samples. I am looking for a system similar, to test all nutrients and compounds within the water of a recirculating hydroponic system. If anyone could take a moment to make some suggestions I’d really appreciate it. A standalone unit would be amazing, but 1 or 2 smaller systems would also work. Thanks!
Thanks for clearing my confusion. Danke sie
I’m overwhelmed by your explanation and I’m grateful that I understood a lot on the differences between GC and HPLC.
Thanks