You can build an expression tree which contains accessing a given property by its name using Expression.Property method. For example, you have the following code.
TestClass obj = new TestClass();
obj.myProperty = 60;
Console.WriteLine(obj.myProperty);
Here is the code that is required to build the same functionality using expression tree.
Expression propertyExpr = Expression.Property(
Expression.Constant(obj),
"myProperty"
);
Console.WriteLine(Expression.Lambda<Func<int>>(propertyExpr).Compile()());