HPLC systems are not like spectrophotometers where you can just pick out one with reasonable features and be done with it. HPLC's are very complex systems with MANY options and required consumables. We do not know you or what your specific needs are so it would be rude to suggest a specific system to you. While I personally do not like fully integrated systems (modular systems allow more flexibility), your needs and funds may not allow for such choices. Fully integrated systems sometimes are less expensive and may meet your needs. ???

Training in how to use and maintain an HPLC system is also something that takes years to become proficient in. Start your quest by defining your goals, needs, expectations and especially your applications for use. What will it be used for? Do you need a simple bench top stand alone system or a fully automated research grade computer software controlled system? What types of detectors will be appropriate for your sample types? How much practical hands-on experience do you have with different systems? What types of local support are available to you? Will you require extensive training and support? Which brands are available to you? Request quotes from them for different systems, and if applicable software.

For professional research labs with applications such as drug analysis and method development, a "basic" system would consist of a Quaternary (4-ch) HPLC pump (0.000-10.000 ml/min), Vacuum Degasser, Diode Array Detector (UV/VIS), Autosampler/Autoinjector and a high-end Chromatography Data System for data acquisition and analysis. This is about as general a system as there is, but there are still many sample types which would not be appropriate for it.

For most University research labs, an entirely different type of system may be appropriate. A simple isocratic pump, single wavelength detector, manual injector valve and data integrator or basic chromatography data system might be fine. There are hundreds of permutations in between so it really depends on the intended use and need. In all cases, don't forget to put aside plenty of funds for all of the normal consumables (e.g. many HPLC columns, HPLC solvents, High Resistance Water system, Tubing, maintenance parts) and training too.

PLEASE do not ask how much these cost. Only when you have narrowed down your choice to a specific system would this be possible and then that info should come from the vendor.

HPLC systems are not like spectrophotometers where you can just pick out one with reasonable features and be done with it. HPLC's are very complex systems with MANY options and required consumables. We do not know you or what your specific needs are so it would be rude to suggest a specific system to you. While I personally do not like fully integrated systems (modular systems allow more flexibility), your needs and funds may not allow for such choices. Fully integrated systems sometimes are less expensive and may meet your needs. ???

Training in how to use and maintain an HPLC system is also something that takes years to become proficient in. Start your quest by defining your goals, needs, expectations and especially your applications for use. What will it be used for? Do you need a simple bench top stand alone system or a fully automated research grade computer software controlled system? What types of detectors will be appropriate for your sample types? How much practical hands-on experience do you have with different systems? What types of local support are available to you? Will you require extensive training and support? Which brands are available to you? Request quotes from them for different systems, and if applicable software.

For professional research labs with applications such as drug analysis and method development, a "basic" system would consist of a Quaternary (4-ch) HPLC pump (0.000-10.000 ml/min), Vacuum Degasser, Diode Array Detector (UV/VIS), Autosampler/Autoinjector and a high-end Chromatography Data System for data acquisition and analysis. This is about as general a system as there is, but there are still many sample types which would not be appropriate for it.

For most University research labs, an entirely different type of system may be appropriate. A simple isocratic pump, single wavelength detector, manual injector valve and data integrator or basic chromatography data system might be fine. There are hundreds of permutations in between so it really depends on the intended use and need. In all cases, don't forget to put aside plenty of funds for all of the normal consumables (e.g. many HPLC columns, HPLC solvents, High Resistance Water system, Tubing, maintenance parts) and training too.

PLEASE do not ask how much these cost. Only when you have narrowed down your choice to a specific system would this be possible and then that info should come from the vendor.

The answer is it depends on your requirement (specifications) and the separations you will perform (not much point of ordering an RID when you need an MSD),  I would only consider;

1.  Waters

2   Agilent

3.  Shimadzu

I agree with Bill.  Also consider the type of detector you will be using.  If it is MS and you wish to perform UPLC, make sure the MS scans fast enough to provide sufficient scans over the peak (generally a minimum of 10 scans for any quantifiable work).  If you are new to HPLC, I would suggest keeping it simple.  Possibly getting a binary system to perform isocratic and simple gradient elution programs would be a good start.  Depending on the types of compounds you are looking to analyze the columns you will need may vary.  Organic molecules with slightly basic or acidic groups can usually all be done with a simple reverse phase C18 column with properly adjusted pH of your aqueous mobile phase.

Thank you Bill, Bruce and Kevin. Your answers really help.

To make my questions more specific, the system is intended to analyse natural products such as plant hormones, sugars, amino acids, and also organic compounds.

I am actually not an expert with HPLC, so I will ask questions that look basic!

1- Will a silica column work with all of these compounds with reasonable efficiency, or each type of analyte will need a specific column?

2- I do not intend to couple HPLC with other techniques (eg MS), so what kind of detector is best, UV or fluorescent?

3- Of course I wish to keep the cost minimal, so a standing alone system is more suitable than a computer-system, is that true?

Thanks for your time.

Answers.

1.  Use a dedicated C18 column (5 cm long) which can perform a reverse phase separation since most molecules are polar.  Silica columns can only do 'normal phase' separations.  

2.  Examine your products and thus the separations that you will perform.  Get an HPLC equipped with a PDA or DAD detector (a UV detector) and a small MSD (or mass spec. detector).  You do not have to purchase a separate 'great, and glorious' MS/MS.  Most molecules do not fluoresce unless they are reacted (Tagged)

3.  Get a computer system (it will save you money eventually).  A single stand alone system can be expanded (LAC/E? or BUS).  In a previous life I went from 0 HPLC's to 8 in 4 years!

A system to analyze: "natural products such as plant hormones, sugars, amino acids, and also organic compounds". *That does not help narrow down the choice of HPLC at all. The only hint it offers is that you may want to consider purchasing a secondary detector such as an RID, FLD, ELSD or CAD since many sugars have weak chromophores with poor detection by UV/VIS (unless you derivatize them).

As already noted, a general purpose gradient system with a UV/VIS detector (a DAD) would be a good investment, but you may want a secondary detector which uses a different detection principle too, depending on YOUR specific samples (RID, FLD, ECD...). Regarding other types of detectors, you mentioned that you specifically do not want an MS detector and that is fine. The detector you should choose should be the type that is most applicable to YOUR samples and your applications. Spend some time and look up the chemical and physical properties of the samples that you wish you run and their detection limits. Base your detector choices on their properties, not our generalizations.

If you can do without automation, then you can save substantial money by only purchasing a manual injector instead of a much more expensive autosampler with built-in autoinjector.

If your budget allows, try and purchase a system with computer controlled data acquisition and data analysis tools. You will have to have this IF you purchase a DAD equipped system. Again, do some homework on your samples and possible methods. That will give you an idea of which features and specifications that YOU need. We are just generalizing as you have listed a WIDE range of sample types so you should explore some example methods online first to get a better idea of which instrument modules are most appropriate.

Regarding columns and types. Please Do Not worry about this at all. There are no Universal HPLC columns so it is likely that you will need several types for several different applications. I also do not recommend starting out with short or UHPLC columns. When first starting out in HPLC, use more conventional sized columns (i.e. 15 or 25 cm length and 4.6 mm ID) as these are more tolerant of larger delay volumes, poor plumbing and non-optimized settings (and also new users like yourself). HPLC Column choices can be made AFTER you spend some time researching the specific methods you plan on using for YOUR samples. Buying or making column choices before you have identified the exact sample and/or method is a huge waste of time and money. It would be like purchasing brake pads for a car BEFORE you have selected the brand or model of car yet.

Thank you Bill for the valuable information and advices.

Yes I intend to opt for manual injection to save the cost autosampler.

This equipment is intended to serve many researchers with a broad range in research interests, that why the applications are expected to be numerous.

In this case, I will have to compile a list of possible applications, study each one in separate and then decide what to buy as a start.

I really appreciate your help.