LINQ GroupBy and select a list of other property values

I have pairs as such

public class AnalyteUnitPair
    {
        public string Analyte { get; set; }
        public string Unit { get; set; }
    }

and I need to turn the list of these into a reshuffled grouped by as such:

what I have

Analyte ="Ce", Unit="g"
Analyte ="Ce", Unit="%"
Analyte ="Ce", Unit="ppm"
Analyte ="Dy", Unit="kg"
Analyte ="Dy", Unit="%"
Analyte ="Dy", Unit="ppm"

what I need is to convert the list above into the list of objects

public class AnalyteUnits
    {
        public string Analyte { get; set; }
        public string Units { get; set; }

    }

that would look like this

Analyte="Ce", Units="g:g,%:%,ppm:ppm";
Analyte="Dy", Units="kg:kg,%:%,ppm:ppm";

Please do not suggest Dictionary, I don’t want to deal with them on the JS side.

Thank you

>Solution :

First group by the Analyte, then you can select all the Units for each group.

var condensed = originalList
    .GroupBy(item => item.Analyte)
    .Select(group => new AnalyteUnitPair()
    {
        Analyte = group.Key,
        Unit = string.Join(",", group.Select(item => $"{item.Unit}:{item.Unit}"))
    });