英国采购需求：氨基酸，维生素系列，购买，购买，质量，在线

I'm reaching out to inquire about high-quality powder options that you may have available. I'm particularly interested in the specifications, including the purity levels, particle size distribution, and any certifications that could support the quality of the product. Additionally, I would like to know about your production capacity and lead times for orders. Could you also provide information on pricing for bulk purchases and any potential discounts for large quantities? If you have samples available, I'd love to review them before making a decision. Looking forward to your response with detailed information so that we can explore potential collaboration!